Date: Tue, 29 Dec 15 01:20:23 GMT
Subject: physics daily 48 new + 27 crosses received   by eprepget 

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arXiv:1512.07921
Date: Thu, 29 Oct 2015 15:39:30 GMT   (9kb)

Title: How to implant a causal $\Theta$ function into the tachyon field
  operator
Authors: Vassili Perepelitsa
Categories: physics.gen-ph
Comments: 8 pages
\\
  A Lorentz-covariant introduction of a causal $\Theta$ function into the
tachyon quantum field operator is suggested. Some features of a
Lorentz-violating (but Lorentz-covariant) tachyon Lagrangian are considered.
\\ ( http://arxiv.org/abs/1512.07921 ,  9kb)
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arXiv:1512.07926
Date: Thu, 24 Dec 2015 22:29:07 GMT   (1092kb,D)

Title: Gaseous time projection chambers for rare event detection: Results from
  the T-REX project. I. Double beta decay
Authors: I. G. Irastorza, F. Aznar, J. Castel, S. Cebri\'an, T. Dafni, J.
  Gal\'an, J. A. Garc\'ia, J. G. Garza, H. G\'omez, D. C. Herrera, F. J. Iguaz,
  G. Luz\'on, H. Mirallas, E. Ruiz, L. Segu\'i, A. Tom\'as
Categories: physics.ins-det hep-ex
Comments: prepared for submission to JCAP
\\
  As part of the T-REX project, a number of R&D and prototyping activities have
been carried out during the last years to explore the applicability of gaseous
Micromegas-read TPCs in rare event searches like double beta decay (DBD), axion
research and low-mass WIMP searches. In both this and its companion paper, we
compile the main results of the project and give an outlook of application
prospects for this detection technique. While in the companion paper we focus
on axions and WIMPs, in this paper we focus on the results regarding the
measurement of the DBD of $^{136}$Xe in a high pressure Xe (HPXe) TPC.
Particularly relevant are the results obtained in Xe + TMA mixtures with
microbulk Micromegas, showing very promising results in terms of gain,
stability of operation, and energy resolution at pressures up to 10 bar. TMA at
levels of $\sim$1\% reduces electron diffusion by a factor of 10 with respect
to pure Xe, improving the quality of the topological pattern, with a positive
impact on the discrimination capability. Operation with a medium size prototype
(30 cm diameter and 38 cm drift) of 1 kg of Xe at 10 bar in the fiducial
volumen has allowed to test the detection concept in realistic experimental
conditions. Microbulk Micromegas are able to image the DBD ionization signature
with high quality while, at the same time, measuring its energy deposition with
a resolution of at least $\sim$3% FWHM @ Q$_{\beta\beta}$, and probably down to
$\sim$1% FWHM. In addition, first results on the topological signature
information show promising background discrimination capabilities out of reach
of other experimental implementations. Moreover, microbulk Micromegas have very
low levels of intrinsic radioactivity, and offer cost-effective scaling-up
options. All these results demonstrate that Micromegas-read HPXe TPC is a very
competitive technique for the next generation DBD experiments.
\\ ( http://arxiv.org/abs/1512.07926 ,  1092kb)
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arXiv:1512.07940
Date: Fri, 25 Dec 2015 00:24:52 GMT   (188kb)

Title: Surface spin-electron acoustic waves in magnetically ordered metals
Authors: Pavel A. Andreev, L. S. Kuz'menkov
Categories: physics.plasm-ph
Comments: 5 pages, 3 figures
\\
  Degenerate plasmas with motionless ions show existence of three surface
waves: the Langmuir wave, the electromagnetic wave, and the zeroth sound.
Applying the separated spin evolution quantum hydrodynamics to half-space
plasma we demonstrate the existence of the surface spin-electron acoustic wave
(SSEAW). We study dispersion of the SSEAW. We show that there is hybridization
between the surface Langmuir wave and the SSEAW at rather small spin
polarization. In the hybridization area the dispersion branches are located
close to each other. In this area there is a strong interaction between these
waves leading to the energy exchange. Consequently, generating the Langmuir
waves with the frequencies close to hybridization area we can generate the
SSEAWs. Thus, we report a method of creation of the SEAWs.
\\ ( http://arxiv.org/abs/1512.07940 ,  188kb)
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arXiv:1512.07952
Date: Fri, 25 Dec 2015 03:39:42 GMT   (29kb)

Title: The initial value problem in Lagrangian drift kinetic theory
Authors: J. W. Burby
Categories: physics.plasm-ph
Comments: 18 pages. Version #1
\\
  Existing high-order variational drift kinetic theories contain unphysical
rapidly varying modes that are not seen at low-orders. These unphysical modes,
which may be rapidly oscillating, damped, or growing, are ushered in by a
failure of conventional high-order drift kinetic theory to preserve the
structure of its parent model's initial value problem (Vlasov-Poisson for
electrostatics, Vlasov-Darwin or Vlasov-Maxwell for electromagnetics.) In
short, the system phase space is unphysically enlarged in conventional
high-order variational drift kinetic theory. I present an alternative,
"renormalized" variational approach to drift kinetic theory that manifestly
respects the parent model's initial value problem. The basic philosophy
underlying this alternate approach is that high-order drift kinetic theory
ought to be derived by truncating the all-orders system phase space Lagrangian
instead of the usual "field+particle" Lagrangian. For the sake of clarity, this
story is told first through the lens of a finite-dimensional toy model of
high-order variational drift kinetics, the analogous full-on drift kinetic
results are discussed subsequently. The renormalized drift kinetic system,
while just as accurate as conventional formulations, does not support the
troublesome rapidly varying mode.
\\ ( http://arxiv.org/abs/1512.07952 ,  29kb)
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arXiv:1512.07968
Date: Fri, 25 Dec 2015 07:00:54 GMT   (7kb)

Title: Technique of production of argon-37 at proton cyclotron and detector for
  measurements
Authors: Askerbek Romazanov
Categories: physics.ins-det
\\
  The technology of production of the isotope Ar-37 at proton cyclotron is
developed. It is based on irradiation of the Cl-37 target with the protons of
energy of a few a MeV. The example of production of tiny amount of Ar-37 is
described and discussed. The detectors to measure the intensity of the sample
is discussed.
\\ ( http://arxiv.org/abs/1512.07968 ,  7kb)
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arXiv:1512.07979
Date: Fri, 25 Dec 2015 08:52:54 GMT   (1099kb)

Title: All-optical pulse compression of broadband microwave signal based on
  stimulated Brillouin scattering
Authors: Xin Long, Weiwen Zou, and Jianping Chen
Categories: physics.optics
Comments: 9 pages,5 figures
\\
  Pulse compression processing based on stimulated Brillouin scattering (SBS)
in an optical fiber is theoretically and experimentally demonstrated. Broadband
microwave signal is electro-optically modulated onto the pump lightwave that is
launched into one end of the fiber. Acoustic wave in the fiber inherits the
amplitude and phase information of the pump lightwave and thus the coupling
between the acoustic wave and pump lightwave leads to the auto-correlated
process of the pump lightwave as well as the modulated microwave signal.
Derivation of the SBS coupling equations shows that the short-pulse probe
lightwave amplified by the pump lightwave possesses the nature of
auto-correlation formula. All-optical pulse compression of the broadband
microwave signal is implemented after a subtraction between the detected probe
pulse with and without SBS. A proof-of-concept experiment is carried out. The
pulse compression of a linear frequency-modulated microwave signal with 1 GHz
sweep range at the carrier frequency of 4.3 GHz is successfully realized, which
well matches the theoretical analysis.
\\ ( http://arxiv.org/abs/1512.07979 ,  1099kb)
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arXiv:1512.08000
Date: Fri, 25 Dec 2015 13:57:44 GMT   (679kb)

Title: Electrically tuned super-capacitors
Authors: Tazima S. Chowdhury and Haim Grebel
Categories: physics.chem-ph cond-mat.mes-hall
Comments: 6 pages, 8 figures
\\
  Fast charging and discharging of large amounts of electrical energy make
super-capacitors ideal for short-term energy storage [1-5]. In its simplest
form, the super-capacitor is an electrolytic capacitor made of an anode and a
cathode immersed in an electrolyte. As for an ordinary capacitor, minimizing
the charge separation distance and increasing the electrode area increase
capacitance. In super-capacitors, charge separation is of nano-meter scale at
each of the electrode interface (the Helmholtz double layer). Making the
electrodes porous increases their effective surface area [6-8]. A separating
layer between the anode and the cathode electrodes is used to minimize
unintentional electrical discharge (Figure 1). Here we show how to increase the
capacitance of super-capacitors by more than 45 percent when modifying the
otherwise passive separator layer into an active diode-like structure. Active
control of super-capacitors may increase their efficiency during charge and
discharge cycles. Controlling ion flow in electro-chemical cells is the first
step toward a new type of ion-transistors.
\\ ( http://arxiv.org/abs/1512.08000 ,  679kb)
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arXiv:1512.08013
Date: Fri, 25 Dec 2015 16:22:23 GMT   (5542kb,D)

Title: Optimal positron-beam excited plasma wakefields in Hollow and Ion-Wake
  channels
Authors: Aakash A. Sahai, T. C. Katsouleas
Categories: physics.plasm-ph hep-ex physics.acc-ph
Comments: Proceedings of IPAC2015, Richmond, VA, USA 3: Alternative Particle
  Sources and Acceleration Techniques A22 - Plasma Wake eld Acceleration
  http://accelconf.web.cern.ch/AccelConf/IPAC2015/papers/wepje001.pdf, 2015
  (ISBN 978-3-95450-168-7) pp 2674-2677
Report-no: WEPJE001
\\
  A positron-beam interacting with the plasma electrons drives radial suck-in,
in contrast to an electron-beam driven blow-out in the over-dense regime,
$n_b>n_0$. In a homogeneous plasma, the electrons are radially sucked-in from
all the different radii. The electrons collapsing from different radii do not
simultaneously compress on-axis driving weak fields. A hollow-channel allows
electrons from its channel-radius to collapse simultaneously exciting coherent
fields. We analyze the optimal channel radius. Additionally, the low ion
density in the hollow allows a larger region with focusing phase which we show
is linearly focusing. We have shown the formation of an ion-wake channel behind
a blow-out electron bubble-wake. Here we explore positron acceleration in the
over-dense regime comparing an optimal hollow-plasma channel to the ion-wake
channel. The condition for optimal hollow-channel radius is also compared. We
also address the effects of a non-ideal ion-wake channel on positron-beam
excited fields.
\\ ( http://arxiv.org/abs/1512.08013 ,  5542kb)
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arXiv:1512.08014
Date: Fri, 25 Dec 2015 16:31:44 GMT   (230kb)

Title: MPX Detectors as LHC Luminosity Monitor
Authors: Andre Sopczak (Institute of Experimental and Applied Physics, Czech
  Technical University in Prague), Babar Ali, Nedaa Asbah, Benedikt Bergmann,
  Khaled Bekhouche, Davide Caforio, Michael Campbell, Erik Heijne, Claude
  Leroy, Anna Lipniacka, Marzio Nessi, Stanislav Pospisil, Frank Seifert,
  Jaroslav Solc, Paul Soueid, Michal Suk, Daniel Turecek, Zdenek Vykydal
Categories: physics.ins-det
Comments: Presented at the IEEE 2015 Nuclear Science Symposium, San Diego, USA
Journal-ref: 2015 Trans. Nucl. Sci. 62 3225
DOI: 10.1109/TNS.2015.2496316
\\
  A network of 16 Medipix-2 (MPX) silicon pixel devices was installed in the
ATLAS detector cavern at CERN. It was designed to measure the composition and
spectral characteristics of the radiation field in the ATLAS experiment and its
surroundings. This study demonstrates that the MPX network can also be used as
a self-sufficient luminosity monitoring system. The MPX detectors collect data
independently of the ATLAS data-recording chain, and thus they provide
independent measurements of the bunch-integrated ATLAS/LHC luminosity. In
particular, the MPX detectors located close enough to the primary interaction
point are used to perform van der Meer calibration scans with high precision.
Results from the luminosity monitoring are presented for 2012 data taken at
sqrt(s) = 8 TeV proton-proton collisions. The characteristics of the LHC
luminosity reduction rate are studied and the effects of beam-beam (burn-off)
and beam-gas (single bunch) interactions are evaluated. The systematic
variations observed in the MPX luminosity measurements are below 0.3% for one
minute intervals.
\\ ( http://arxiv.org/abs/1512.08014 ,  230kb)
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arXiv:1512.08024
Date: Fri, 25 Dec 2015 18:16:46 GMT   (6499kb,D)

Title: In vacuum diamond sensor scanner for beam halo measurements in the beam
  line at the KEK Accelerator Test Facility
Authors: Shan Liu, Frederic Bogard, Patrick Cornebise, Angeles Faus-Golfe,
  Nuria Fuster-Mart\'inez, Erich Griesmayer, Hayg Guler, Viacheslav Kubytskyi,
  Christophe Sylvia, Tauchi Toshiaki, Nobuhiro Terunuma, Philip Bambade
Categories: physics.acc-ph
\\
  The investigation of beam halo transverse distributions is important for the
understanding of beam losses and the control of backgrounds in Future Linear
Colliders (FLC). A novel in vacuum diamond sensor (DSv) scanner with four
strips has been designed and developed for the investigation of the beam halo
transverse distributions and also for the diagnostics of Compton recoil
electrons after the interaction point (IP) of ATF2, a low energy (1.3 GeV)
prototype of the final focus system for the ILC and CLIC linear collider
projects. Using the DSv, a dynamic range of $\sim10^6$ has been successfully
demonstrated and confirmed for the first time by simultaneous beam core
($\sim10^9$ electrons) and beam halo ($\sim10^3$ electrons) measurements at
ATF2. This report presents the characterization, performance studies and tests
of the diamond sensors using an $\alpha$ source as well as using the electron
beams at PHIL, a low energy ($< 10$ MeV) photo-injector at LAL, and at ATF2.
First beam halo measurement results using the DSv at ATF2 with different beam
intensities and vacuum levels are also presented. Such measurements not only
allow one to evaluate the different sources of beam halo generation but also to
define the requirements for a suitable collimation system to be installed at
ATF2, as well as to optimize its performance during future operation.
\\ ( http://arxiv.org/abs/1512.08024 ,  6499kb)
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arXiv:1512.08033
Date: Fri, 25 Dec 2015 20:32:00 GMT   (15kb)

Title: Understanding Zero-Point Energy in the Context of Classical
  Electromagnetism
Authors: Timothy H. Boyer
Categories: physics.class-ph
Comments: 19 pages
\\
  Today's textbooks of electromagnetism give the particular solution to
Maxwell's equations involving the integral over the charge and current sources
at retarded times. However, the texts fail to emphasize the role played by the
choice of the boundary conditions corresponding to solutions of the homogeneous
Maxwell equations. Here we discuss the role of these boundary conditions for an
experimenter with a hypothetical charged harmonic oscillator as his equipment.
We describe the observations of the experimenter when located near a radio
station or immersed in thermal radiation at temperature T. The classical
physicists at the end of the 19th century chose the homogeneous boundary
conditions for Maxwell's equation based upon the experimental observations of
Lummer and Pringsheim which measured only the thermal radiation which exceeded
the random radiation surrounding their measuring equipment. Today at the
beginning of the 21st century, classical physicists must choose the homogeneous
boundary conditions for Maxell's equations to correspond to the full radiation
spectrum revealed by the recent Casimir force measurements which detect all the
radiation surrounding conducting parallel plates, including the radiation
absorbed and emitted by the plates themselves. The random classical radiation
spectrum revealed by the Casimir force measurements includes electromagnetic
zero-point radiation, which is missing from the spectrum measured by Lummer and
Pringsheim, and which cannot be eliminated by going to zero temperature. This
zero-point radiation will lead to zero-point energy for all systems which have
electromagnetic interactions. Thus the choice of the boundary conditions on the
homogeneous Maxwell equations is intimately related to the ideas of zero-point
energy and non-radiating ground states which are introduced in classes of
modern physics.
\\ ( http://arxiv.org/abs/1512.08033 ,  15kb)
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arXiv:1512.08042
Date: Fri, 25 Dec 2015 21:50:22 GMT   (1117kb)

Title: DSMC-LBM mapping scheme for rarefied and non-rarefied gas flows
Authors: G. Di Staso (1), H.J.H Clercx (1), S. Succi (3), F. Toschi (1, 2 and
  3) ((1) Department of Applied Physics, Eindhoven University of Technology,
  Den Dolech 2, 5600 MB, Eindhoven, Netherlands, (2) Department of Mathematics
  and Computer Science, Eindhoven University of Technology, Den Dolech 2, 5600
  MB, Eindhoven, Netherlands, (3) Istituto per le Applicazioni del Calcolo,
  Consiglio Nazionale delle Ricerche, Via dei Taurini 19, 00185, Rome, Italy)
Categories: physics.flu-dyn
Comments: Submitted to Journal of Computational Science
MSC-class: 76P05, 82B80, 82B40
\\
  We present the formulation of a kinetic mapping scheme between the Direct
Simulation Monte Carlo (DSMC) and the Lattice Boltzmann Method (LBM) which is
at the basis of the hybrid model used to couple the two methods in view of
efficiently and accurately simulate isothermal flows characterized by variable
rarefaction effects. Owing to the kinetic nature of the LBM, the procedure we
propose ensures to accurately couple DSMC and LBM at a larger Kn number than
usually done in traditional hybrid DSMC-Navier-Stokes equation models. We show
the main steps of the mapping algorithm and illustrate details of the
implementation. Good agreement is found between the moments of the single
particle distribution function as obtained from the mapping scheme and from
independent LBM or DSMC simulations at the grid nodes where the coupling is
imposed. We also show results on the application of the hybrid scheme based on
a simpler mapping scheme for plane Poiseuille flow at finite Kn number.
Potential gains in the computational efficiency assured by the application of
the coupling scheme are estimated for the same flow.
\\ ( http://arxiv.org/abs/1512.08042 ,  1117kb)
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arXiv:1512.08045
Date: Fri, 25 Dec 2015 22:46:04 GMT   (199kb)

Title: Frequency moments of the Coulomb dynamic structure factor and related
  integrals
Authors: Basil J B Crowley
Categories: physics.plasm-ph
Comments: 28 pages of which 4 blank. No figures
\\
  This report addresses the moments, ${\mathfrak{G}_n}\left( {\mathbf{q}}
\right) = \int_{ - \infty }^{ + \infty } {{\omega ^n}S\left(
{{\mathbf{q}},\omega } \right)\mathrm{d}\omega },\,n \in \mathbb{N},\,n \geq -
1$, of the quantum mechanical dynamic structure factor $S\left(
{{\mathbf{q}},\omega } \right)$ for a one-component Coulomb plasma in
thermodynamic equilibrium. The Fluctuation Dissipation Theorem relates these
moments to integrals involving the imaginary part of the inverse longitudinal
dielectric function, with the odd moments in particular being equivalent to the
odd moments of the imaginary part of the inverse dielectric function.
Application of the Generalized Plasmon Pole Approximation arXiv:1508.05606
[physics.plasm-ph] to a weakly-coupled non-degenerate plasma, leads to general
formulae expressed in terms of polynomial functions. Explicit forms of these
functions are given for $n \leq 20$. These formulae are generalized to
degenerate and partially degenerate plasmas, in small-$\mathbf{q}$
(long-wavelength) regimes.
\\ ( http://arxiv.org/abs/1512.08045 ,  199kb)
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arXiv:1512.08094
Date: Sat, 26 Dec 2015 10:10:10 GMT   (1697kb)

Title: Empirical Validation of a Thermal Model of a Complex Roof Including
  Phase Change Materials
Authors: St\'ephane Guichard, Fr\'ed\'eric Miranville (PIMENT), Dimitri Bigot
  (PIMENT), Bruno Malet-Damour (PIMENT), Teddy Libelle (PIMENT), Harry Boyer
  (PIMENT)
Categories: physics.class-ph
Journal-ref: Energies, MDPI, 2016, 9 (1)
DOI: 10.3390/en9010009
\\
  This paper deals with the empirical validation of a building thermal model
using a phase change material (PCM) in a complex roof. A mathematical model
dedicated to phase change materials based on the heat apparent capacity method
was implemented in a multi-zone building simulation code, the aim being to
increase understanding of the thermal behavior of the whole building with PCM
technologies. To empirically validate the model, the methodology is based both
on numerical and experimental studies. A parametric sensitivity analysis was
performed and a set of parameters of the thermal model have been identified for
optimization. The use of a generic optimization program called GenOpt coupled
to the building simulation code enabled to determine the set of adequate
parameters. We first present the empirical validation methodology and main
results of previous work. We then give an overview of GenOpt and its coupling
with the building simulation code. Finally, once the optimization results are
obtained, comparisons of thermal model of PCM with measurements are found to be
acceptable and are presented.
\\ ( http://arxiv.org/abs/1512.08094 ,  1697kb)
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arXiv:1512.08109
Date: Sat, 26 Dec 2015 13:16:57 GMT   (422kb)

Title: Light refraction by water as a rationale for the Poggendorff illusion
Authors: Sergey I. Bozhevolnyi
Categories: physics.optics physics.bio-ph
Comments: 9 pages, 6 figures
\\
  The Poggendorff illusion in its classical form of parallel lines interrupting
a transversal is viewed from the perspective of being related to the everyday
experience of observing the light refraction in water. It is argued that, if
one considers a transversal to be a light ray in air and the parallel lines to
form an occluding strip of a medium with the refractive index being between
that of air and water, then one should be able to account, both qualitatively
and quantitatively, for most of the features associated with the Poggendorff
illusion. Statistical treatment of the visual experiments conducted with 7
participants, each analysing 50 configurations having different intercepting
angles and strip widths, resulted in the effective refractive index of the
occluding strip N = 1.13 +/- 0.15, which is sufficiently close to the average
(between that of water and air) refractive index of ~ 1.17. It is further
argued that the same mechanism can also be employed to account for many
variants of the Poggendorff illusion, including the corner-Poggendorff pattern,
as well as for the Hering illusion.
\\ ( http://arxiv.org/abs/1512.08109 ,  422kb)
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arXiv:1512.08118
Date: Sat, 26 Dec 2015 14:30:42 GMT   (3077kb,D)

Title: Reynolds-dependence of turbulent skin-friction drag reduction induced by
  spanwise forcing
Authors: Davide Gatti and Maurizio Quadrio
Categories: physics.flu-dyn
\\
  This paper examines how increasing the value of the Reynolds number $Re$
affects the ability of spanwise-forcing techniques to yield turbulent
skin-friction drag reduction. The control strategy is the streamwise-travelling
waves of spanwise wall velocity (Quadrio {\em et al. J. Fluid Mech.}, vol. 627,
2009, pp. 161--178). The study builds upon an extensive drag-reduction database
created with Direct Numerical Simulation of a turbulent channel flow for two,
5-fold separated values of $Re$, namely $Re_\tau=200$ and $Re_\tau=1000$. The
sheer size of the database, which for the first time systematically addresses
the amplitude of the forcing, allows a comprehensive view of the drag-reducing
characteristics of the traveling waves, and enables a detailed description of
the changes occurring when $Re$ increases. The effect of using a viscous
scaling based on the friction velocity of either the non-controlled flow or the
drag-reduced flow is described. In analogy with other wall-based drag reduction
techniques, like for example riblets, the performance of the travelling waves
is well described by a vertical shift of the logarithmic portion of the mean
streamwise velocity profile. Except when $Re$ is very low, this shift remains
constant with $Re$, at odds with the percentage reduction of the friction
coefficient, which is known to present a mild, logarithmic decline. Our new
data agree with the available literature, which is however mostly based on
low-$Re$ information and hence predicts a quick drop of maximum drag reduction
with $Re$. The present study supports a more optimistic scenario, where for an
airplane at flight Reynolds numbers a drag reduction of nearly 30\% would still
be possible thanks to the travelling waves.
\\ ( http://arxiv.org/abs/1512.08118 ,  3077kb)
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arXiv:1512.08137
Date: Sat, 26 Dec 2015 20:13:37 GMT   (149kb,D)

Title: N-electron valence state perturbation theory based on a density matrix
  renormalization group reference function, with applications to the chromium
  dimer and poly-p-phenylene vinylene
Authors: Sheng Guo, Mark A. Watson, Weifeng Hu, Qiming Sun, and Garnet Kin-Lic
  Chan
Categories: physics.chem-ph
Comments: 28 pages, 5 figures
\\
  The strongly-contracted variant of second order N -electron valence state
perturbation theory (NEVPT2) is an efficient perturbative method to treat
dynamic correlation without the problems of intruder states or level shifts,
while the density matrix renormalization group (DMRG) provides the capability
to tackle static correlation in large active spaces. We present a combination
of the DMRG and strongly-contracted NEVPT2 (DMRG-SC-NEVPT2) that uses an
efficient algorithm to compute high order reduced density matrices from DMRG
wave functions. The capabilities of DMRG-SC-NEVPT2 are demonstrated on
calculations of the chromium dimer potential energy curve at the basis set
limit, and the excitation energies of poly-p-phenylene vinylene(PPV).
\\ ( http://arxiv.org/abs/1512.08137 ,  149kb)
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arXiv:1512.08139
Date: Sat, 26 Dec 2015 20:28:23 GMT   (977kb)

Title: Ultimately Thin Metasurface Wave Plates
Authors: David Keene, Matthew LePain and Maxim Durach
Categories: physics.optics cond-mat.mes-hall cond-mat.mtrl-sci
Comments: 12 pages, 7 figures
\\
  Optical properties of a metasurface which can be considered a monolayer of
two classical uniaxial metamaterials, parallel-plate and nanorod arrays, are
investigated. It is shown that such metasurface acts as an ultimately thin
sub-50 nm wave plate. This is achieved via an interplay of epsilon-near-zero
and epsilon-near-pole behavior along different axes in the plane of the
metasurface allowing for extremely rapid phase difference accumulation in very
thin metasurface layers. These effects are shown to not be disrupted by
non-locality and can be applied to the design of ultrathin wave plates,
Pancharatnam-Berry phase optical elements and plasmon-carrying optical torque
wrench devices.
\\ ( http://arxiv.org/abs/1512.08139 ,  977kb)
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arXiv:1512.08151
Date: Sat, 26 Dec 2015 22:19:53 GMT   (355kb,D)

Title: A unified slip boundary condition for flow over a surface
Authors: Joseph John Thalakkottor and Kamran Mohseni
Categories: physics.flu-dyn physics.chem-ph
Comments: 11 pages, 14 figure
\\
  Interface between two phases of matter are ubiquitous in nature and
technology. Determining the correct velocity condition at an interface is
essential for understanding and designing of flows over a surface. We
demonstrate that both the widely used no-slip and the Navier and Maxwell slip
boundary conditions do not capture the complete physics associated with complex
problems, such as spreading of liquids or corner flows. Hence, we present a
unified boundary condition that is applicable to a wide-range of flow problems.
\\ ( http://arxiv.org/abs/1512.08151 ,  355kb)
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arXiv:1512.08170
Date: Sun, 27 Dec 2015 05:05:05 GMT   (519kb)

Title: A New Mathematical Formulation of the Governing Equations for the
  Chemical Compositional Simulation
Authors: Bakhbergen E. Bekbauov, Aidarkhan Kaltayev, Abdumauvlen Berdyshev
Categories: physics.flu-dyn
\\
  It is the purpose of this work to develop new approach for chemical
compositional reservoir simulation, which may be regarded as a sequential
method. The development process can be roughly divided into the following two
stages: (1) development of a new mathematical formulation for the sequential
chemical compositional reservoir simulation, (2) implementation of a sequential
solution approach for chemical compositional reservoir simulation based on the
formulation described in this paper. This paper addresses the first stage of
the development process by presenting a new mathematical formulation of the
chemical compositional reservoir flow equations for the sequential simulation.
The newly developed mathematical formulation is extended from the model
formulation used in existing chemical compositional simulators. During the
model development process, it was discovered that the currently used chemical
compositional model estimates the adsorption effect on the transport of a
component reasonably well but it violates the principle of mass conservation.
The energy conservation equation in the currently used chemical compositional
model does not consider any change in the effective pore size caused by
adsorption, which leads to inconsistency between the overall compositional
balance equations and the energy conservation equation by violating
conservation of energy. With these partial differential equations as governing
equations, several simulators have been developed. In this article, we propose
a formulation to model the change in pore volume due to adsorption that
satisfies the conservation laws for mass and energy, and allows applying a
sequential solution approach.
\\ ( http://arxiv.org/abs/1512.08170 ,  519kb)
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\\
arXiv:1512.08200
Date: Sun, 27 Dec 2015 10:45:17 GMT   (299kb)

Title: Fully Developed Turbulence in the view of Horizontal Visibility Graphs
Authors: Pouya Manshour, M. Reza Rahimi Tabar and Joachim Peinke
Categories: physics.flu-dyn cond-mat.dis-nn physics.data-an
DOI: 10.1088/1742-5468/2015/08/P08031
\\
  We employ the horizontal visibility algorithm to map the velocity and
acceleration time series in turbulent flows with different Reynolds numbers,
onto complex networks. The universal nature of velocity fluctuations in high
Reynolds turbulent Helium flow is found to be inherited in the corresponding
network topology. The degree distributions of the acceleration series are shown
to have stretched exponential forms with the Reynolds number dependent fitting
parameter. Furthermore, for acceleration time series, we find a transitional
behavior in terms of the Reynolds number in all network features which is in
agreement with recent empirical studies.
\\ ( http://arxiv.org/abs/1512.08200 ,  299kb)
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\\
arXiv:1512.08205
Date: Sun, 27 Dec 2015 11:37:07 GMT   (145kb)

Title: Complex Network Approach to the Fractional Time Series
Authors: Pouya Manshour
Categories: physics.data-an physics.soc-ph
Journal-ref: Chaos 25, 103105 (2015)
DOI: 10.1063/1.4930839
\\
  In order to extract the correlation information inherited in a stochastic
time series, the visibility graph algorithm has been recently proposed, by
which a time series can be mapped onto a complex network. We demonstrate that
the visibility algorithm is not an appropriate one to study the correlation
aspects of a time series. We then employ the horizontal visibility algorithm,
as a much simpler one, to map the fractional processes onto complex networks.
The parabolic exponential functions are found to ?fit with the corresponding
degree distributions, with Hurst dependent ?fitting parameter. Further, we take
into account other topological properties such as the maximum eigenvalue of the
adjacency matrix and the degree assortativity, and show that such topological
quantities can also be used to predict the Hurst exponent, with an exception
for the antipersistent fractional Gaussian noises. To solve this problem, we
take into account the Spearman correlation coefficient between the node's
degree and its corresponding value in the original time series.
\\ ( http://arxiv.org/abs/1512.08205 ,  145kb)
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\\
arXiv:1512.08206
Date: Sun, 27 Dec 2015 11:42:20 GMT   (97kb)

Title: Quantum Ring-Polymer Contraction Method: Including nuclear quantum
  effects at no additional computational cost in comparison to ab-initio
  molecular dynamics
Authors: Chris John, Thomas Spura, Scott Habershon and Thomas D. K\"uhne
Categories: physics.chem-ph cond-mat.stat-mech physics.class-ph physics.comp-ph
Comments: 9 pages, 4 figures, 2 tables
\\
  We present a simple and accurate computational method, which facilitates
ab-initio path-integral molecular dynamics simulations, where the quantum
mechanical nature of the nuclei is explicitly taken into account, at
essentially no additional computational cost in comparison to the corresponding
calculation using classical nuclei. The predictive power of the proposed
quantum ring-polymer contraction method is demonstrated by computing various
static and dynamic properties of liquid water at ambient conditions. This
development permits to routinely include nuclear quantum effects in ab-initio
molecular dynamics simulations.
\\ ( http://arxiv.org/abs/1512.08206 ,  97kb)
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\\
arXiv:1512.08208
Date: Sun, 27 Dec 2015 12:02:05 GMT   (875kb,D)

Title: High refractive index immersion liquid for super-resolution 3D imaging
  using sapphire-based aNAIL optics
Authors: Junaid M. Laskar, P. Shravan Kumar, Stephan Herminghaus, Karen E.
  Daniels and Matthias Schr\"oter
Categories: physics.optics
\\
  Optically-transparent immersion liquids with refractive index (n ~ 1.77) to
match sapphire-based aplanatic numerical aperture increasing lens (aNAIL) are
necessary for achieving deep 3D imaging with high spatial resolution. We report
that antimony tribromide (SbBr$_{3}$) salt dissolved in liquid diiodomethane
(CH$_{2}$I$_{2}$) provides a new high refractive index immersion liquid for
optics applications. The refractive index is tunable from n = 1.74 (pure) to n
= 1.873 (saturated), by adjusting either salt concentration or temperature;
this allows it to match (or even exceed) the refractive index of sapphire.
Importantly, the solution gives excellent light transmittance in the
ultraviolet to near-infrared range, an improvement over commercially-available
immersion liquids. This refractive index matched immersion liquid formulation
has enabled us to develop a sapphire-based aNAIL objective that has both high
numerical aperture (NA = 1.17) and long working distance (WD = 12 mm). This
opens up new possibilities for deep 3D imaging with high spatial resolution.
\\ ( http://arxiv.org/abs/1512.08208 ,  875kb)
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\\
arXiv:1512.08232
Date: Sun, 27 Dec 2015 15:53:05 GMT   (566kb)

Title: Nanoscale Field Effect Optical Modulators Based on Depletion of
  Epsilon-Near-Zero Films
Authors: Zhaolin Lu, Peichuan Yin, and Kaifeng Shi
Categories: physics.optics
Comments: 9 pages, 4 figures
\\
  The field effect in metal-oxide-semiconductor (MOS) capacitors plays a key
role in field-effect transistors (FETs), which are the fundamental building
blocks of modern digital integrated circuits. Recent works show that the field
effect can also be used to make optical/plasmonic modulators. In this paper, we
report field effect electro-absorption modulators (FEOMs) each made of an
ultrathin epsilon-near-zero (ENZ) film, as the active material, sandwiched in a
silicon or plasmonic waveguide. Without a bias, the ENZ film maximizes the
attenuation of the waveguides and the modulators work at the OFF state;
contrariwise, depletion of the carriers in the ENZ film greatly reduces the
attenuation and the modulators work at the ON state. The double capacitor
gating scheme is used to enhance the modulation by the field effect. According
to our simulation, extinction ratio up to 3.44 dB can be achieved in a 500-nm
long Si waveguide with insertion loss only 0.71 dB (85.0%); extinction ratio up
to 7.86 dB can be achieved in a 200-nm long plasmonic waveguide with insertion
loss 1.11 dB (77.5%). The proposed modulators may find important applications
in future on-chip or chip-to-chip optical interconnection.
\\ ( http://arxiv.org/abs/1512.08232 ,  566kb)
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\\
arXiv:1512.08247
Date: Sun, 27 Dec 2015 17:23:57 GMT   (2211kb,D)

Title: Remembering a Great Teacher
Authors: Alberto Sirlin
Categories: physics.hist-ph hep-ph hep-th
Comments: 17 pages
\\
  The article is a recollection of the memorable experience of attending a
course on Quantum Mechanics given by Feynman in Brasil, as well as several
meetings and exchanges Daniele Amati and I had with him over many years, in
both the U.S. and Europe. The article also includes a small sample of the
problems assigned in the course, a one-page guide, hand-written by Feynman, to
study QED on the basis of two of his most important papers, and his reply to a
letter of congratulations that the author had sent to him on the occasion of
his Nobel Prize Award.
\\ ( http://arxiv.org/abs/1512.08247 ,  2211kb)
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\\
arXiv:1512.08270
Date: Thu, 24 Dec 2015 03:35:12 GMT   (3720kb)

Title: DDEC6: A Method for Computing Even-Tempered Net Atomic Charges in
  Periodic and Nonperiodic Materials
Authors: Thomas A. Manz and Nidia Gabaldon Limas
Categories: physics.chem-ph cond-mat.mtrl-sci physics.comp-ph
Comments: 97 pages, 20 figures, 35 tables, plus 25 pages Supporting Information
\\
  Net atomic charges (NACs) are widely used in all chemical sciences to
concisely summarize key information about the partitioning of electrons among
atoms in materials. Although widely used, there is currently no atomic
population analysis method suitable for being used as a default method in
quantum chemistry programs. To address this challenge, we introduce a new
atoms-in-materials method with the following nine properties: (1) exactly one
electron distribution is assigned to each atom, (2) core electrons are assigned
to the correct host atom, (3) NACs are formally independent of the basis set
type because they are functionals of the total electron distribution, (4) the
assigned atomic electron distributions give an efficiently converging
polyatomic multipole expansion, (5) the assigned NACs usually follow Pauling
scale electronegativity trends, (6) NACs for a particular element have good
transferability among different conformations that are equivalently bonded, (7)
the assigned NACs are chemically consistent with the assigned atomic spin
moments, (8) the method has predictably rapid and robust convergence to a
unique solution, and (9) the computational cost of charge partitioning scales
linearly with increasing system size. Across a broad range of material types,
the DDEC6 NACs reproduced electron transfer trends, core electron binding
energy shift trends, and electrostatic potentials across multiple system
conformations with excellent accuracy compared to other charge assignment
methods. Due to non-nuclear attractors, Bader's quantum chemical topology could
not assign NACs for some of these materials. The DDEC6 method alleviates the
bifurcation or runaway charges problem exhibited by earlier DDEC variants and
the Iterative Hirshfeld method. These characteristics make the DDEC6 method
ideally suited for use as a default charge assignment method in quantum
chemistry programs.
\\ ( http://arxiv.org/abs/1512.08270 ,  3720kb)
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\\
arXiv:1512.08277
Date: Sun, 27 Dec 2015 21:16:30 GMT   (1036kb)

Title: Electrically Switchable Metadevices
Authors: Osman Balci,Ertugrul Karademir,Semih Cakmakyapan, Nurbek Kakenov, Emre
  Ozan Polat, Humeyra Caglayan, Ekmel Ozbay, Coskun Kocabas
Categories: physics.optics cond-mat.mtrl-sci
Comments: 17 pages, 5 figures
\\
  Metamaterials bring sub-wavelength resonating structures together to overcome
the limitations of conventional matter. The realization of active metadevices
has been an outstanding challenge that requires electrically reconfigurable
components operating over a broad spectrum with a wide dynamic range. The
existing capability of metamaterials, however, is not sufficient to realize
this goal. Here, integrating passive metamaterials with active graphene
devices, we demonstrated a new class of electrically controlled metadevices.
These metadevices enable efficient control of both amplitude (>50 dB) and phase
(>90 deg.) of electromagnetic waves. In this hybrid system, graphene operates a
tunable Drude metal that controls the radiation of the passive metamaterials.
Furthermore, by integrating individually addressable arrays of metadevices, we
demonstrated a new class of spatially varying digital metasurfaces where the
local dielectric constant can be reconfigured with a bias voltage. Our approach
is general enough to implement various metamaterial systems that could yield
new applications ranging from electrically switchable clocking devices to
adaptive camouflage systems.
\\ ( http://arxiv.org/abs/1512.08277 ,  1036kb)
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\\
arXiv:1512.08281
Date: Sun, 27 Dec 2015 21:47:28 GMT   (2045kb,D)

Title: Latitudinal libration driven flows in triaxial ellipsoids
Authors: S. Vantieghem, D. C\`ebron and J. Noir
Categories: physics.flu-dyn
Journal-ref: J. Fluid Mech. (2015), 771, pp. 193-228
DOI: 10.1017/jfm.2015.130,
\\
  Motivated by understanding the liquid core dynamics of tidally deformed
planets and moons, we present a study of incompressible flow driven by
latitudinal libration within rigid triaxial ellipsoids. We first derive a
laminar solution for the inviscid equations of motion under the assumption of
uniform vorticity flow. This solution exhibits a res- onance if the libration
frequency matches the frequency of the spin-over inertial mode. Furthermore, we
extend our model by introducing a reduced model of the effect of viscous Ekman
layers in the limit of low Ekman number (Noir and C\`ebron 2013). This
theoretical approach is consistent with the results of Chan et al. (2011) and
Zhang et al. (2012) for spheroidal geometries. Our results are validated
against systematic three-dimensional numerical simulations. In the second part
of the paper, we present the first linear sta- bility analysis of this uniform
vorticity flow. To this end, we adopt different methods (Lifschitz and Hameiri
1991; Gledzer and Ponomarev 1977) that allow to deduce upper and lower bounds
for the growth rate of an instability. Our analysis shows that the uniform
vorticity base flow is prone to inertial instabilities caused by a parametric
resonance mechanism. This is confirmed by a set of direct numerical
simulations. Applying our results to planetary settings, we find that neither a
spin-over resonance nor an inertial instability can exist within the liquid
core of the Moon, Io and Mercury.
\\ ( http://arxiv.org/abs/1512.08281 ,  2045kb)
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\\
arXiv:1512.08282
Date: Sun, 27 Dec 2015 21:54:18 GMT   (539kb)

Title: Positron Bunch Radiation in the System of Tightly-Packed Nanotubes
Authors: Koryun Gevorgyan, Lekdar Gevorgian and Hayk Gevorgyan
Categories: physics.acc-ph physics.plasm-ph
\\
  The problem of channeling radiation of positron bunch in the system of packed
nanotubes was investigated in the present work. Used the model of harmonic
potential which is justified since on the one hand the number of positrons in
the region near the axis of nanotube is small, and on the other hand their
contribution to the formation of the total radiation is also small. The problem
is solved in the dipole approximation. The radiation at first harmonic occurs
at zero angle too. At zero angle are radiated both extremely hard and extremely
soft photons due to the medium polarization. The frequency-angular distribution
of number of emitted photons was received. The distribution does not depend on
the azimuthal angle, since the task has cylindrical symmetry. Radiation at the
zero angle is fully circularly polarized. For formation of radiation there is
an energy threshold: lower threshold is due to the polarization of medium, the
upper threshold depends on the oscillation amplitude of channelling positrons.
When the bunch energy coincides with the upper threshold then in radiation
contribute all channeled positrons. Each positron in average radiates one
photon. Thus is formed intensive, quasi-monochromatic and circularly olarized
X-ray photon beam which may have important practical application.
\\ ( http://arxiv.org/abs/1512.08282 ,  539kb)
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\\
arXiv:1512.08288
Date: Sun, 27 Dec 2015 23:10:55 GMT   (166kb)

Title: Features in Energy Accumulation in Double Layer on the surface of
  Graphene Material
Authors: Mikhail Evgenievich Kompan, Vladislav Gennadievich Malyshkin,
  Alexander Yurievich Maslov, Viktor Petrovich Kuznetsov, Viktor Aleksandrovich
  Krivchenko
Categories: physics.chem-ph cond-mat.mtrl-sci
\\
  An application of quantum size carbon structures--graphenes as electrodes of
supercapacitors is studied. A fundamental limit of energy and power density
arising from quantum nature of objects due to singularity in graphene density
of states near Dirac point is determined and technical solutions to partially
offset the negative factors are considered. The maximum possible specific
capacitance of nanostructured electrode materials is determined.
\\ ( http://arxiv.org/abs/1512.08288 ,  166kb)
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\\
arXiv:1512.08304
Date: Mon, 28 Dec 2015 02:11:45 GMT   (153kb,D)

Title: Interferometric superlocalization of two incoherent optical point
  sources
Authors: Ranjith Nair and Mankei Tsang
Categories: physics.optics quant-ph
Comments: 15 pages, 6 figures; Submitted
\\
  A novel interferometric method -- SLIVER (Super Localization by Image
inVERsion interferometry) -- is proposed for estimating the separation of two
incoherent point sources with a mean squared error that does not deteriorate as
the sources are brought closer. The essential component of the interferometer
is an image inversion device that inverts the field in the transverse plane
about the optical axis, assumed to pass through the centroid of the sources.
The performance of the device is analyzed using the Cram\'er-Rao bound applied
to the statistics of counting using photon-resolving and on-off detectors. The
analysis is supported by Monte-Carlo simulations of the maximum likelihood
estimator for the source separation, demonstrating the superlocalization
effect. The results are valid for any imaging system with a circularly
symmetric point-spread function.
\\ ( http://arxiv.org/abs/1512.08304 ,  153kb)
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\\
arXiv:1512.08308
Date: Mon, 28 Dec 2015 02:36:43 GMT   (892kb)

Title: Robust scatter correction method for cone-beam CT using an
  interlacing-slit plate
Authors: Kuidong Huang, Zhe Xu, Dinghua Zhang, Hua Zhang, Wenlong Shi
Categories: physics.med-ph
\\
  Cone-beam computed tomography (CBCT) has been widely used in medical imaging
and industrial nondestructive testing, but the presence of scattered radiation
will cause significant reduction of image quality. In this article, a robust
scatter correction method for CBCT using an interlacing-slit plate (ISP) is
carried out for convenient practice. Firstly, a Gaussian filtering method is
proposed to compensate the missing data of the inner scatter image, and
simultaneously avoid too-large values of calculated inner scatter and smooth
the inner scatter field. Secondly, an interlacing-slit scan without detector
gain correction is carried out to enhance the practicality and convenience of
the scatter correction method. Finally, a denoising step for scatter-corrected
projection images is added in the process flow to control the noise
amplification. The experimental results show that the improved method can not
only make the scatter correction more robust and convenient, but also achieve a
good quality of scatter-corrected slice images.
\\ ( http://arxiv.org/abs/1512.08308 ,  892kb)
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\\
arXiv:1512.08318
Date: Mon, 28 Dec 2015 05:17:50 GMT   (914kb)

Title: Phase statistics of light wave reflected from one-dimensional optical
  disordered media and its effects on light transport properties
Authors: Prabhakar Pradhan
Categories: physics.optics
Comments: 18 pages, 8 figures. arXiv admin note: substantial text overlap with
  arXiv:cond-mat/9703255
\\
  Light wave reflection from optical disordered media is always associate with
its phase, and the phase statistics influence the reflection statistics. We
report a detailed numerical study of the statistics of the reflection
coefficient RR* and its associated phase(theta) for plane electromagnetic waves
reflected from one dimensional (1D) Gaussian white-noise optical disordered
media, ranging from weak to strong disordered regimes. We solve numerically the
full Fokker-Planck (FP) equation for the joint probability distribution in the
RR* - phase(theta) space for different lengths of the sample with different
disorder strengths. The statistical optical transport properties of 1D optical
disordered media are calculated using the full FP equation numerically. This
constitutes a complete solution for the reflection phase statistics and its
effects on light transport properties in a 1D Gaussian white-noise disordered
optical potentials. Our results show the regime of the validation of the random
phase approximations (RPA) or uniform phase distribution, within the Born
approximation, as well as the contribution of the phase statistics to the
different reflection averages for strong disorder regimes. Results of the
previous work reported in the literature relative to the present work also been
reviewed and discussed
\\ ( http://arxiv.org/abs/1512.08318 ,  914kb)
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\\
arXiv:1512.08336
Date: Mon, 28 Dec 2015 07:38:52 GMT   (2447kb)

Title: Bright-field Nanoscopy: Visualizing Nano-structures with Localized
  Optical Contrast Using a Conventional Microscope
Authors: Swathi Suran, Krishna Bharadwaj, Srinivasan Raghavan and Manoj M.
  Varma
Categories: physics.optics cond-mat.mes-hall
\\
  Most methods for optical visualization beyond the diffraction limit rely on
fluorescence emission by molecular tags. Here, we report a method for
visualization of nanostructures down to a few nanometers using a conventional
bright-field microscope without requiring additional molecular tags such as
fluorophores. The technique, Bright-field Nanoscopy, is based on the strong
thickness dependent color of ultra-thin germanium on an optically thick gold
film. We demonstrate the visualization of grain boundaries in chemical vapour
deposited single layer graphene and the detection of single 40 nm Ag
nanoparticles. We estimate a size detection limit of about 2 nm using this
technique. In addition to visualizing nano-structures, this technique can be
used to probe fluid phenomena at the nanoscale, such as transport through 2D
membranes. We estimated the water transport rate through a 1 nm thick polymer
film using this technique, as an illustration. Further, the technique can also
be extended to study the transport of specific ions in the solution. It is
anticipated that this technique will find use in applications ranging from
single-nanoparticles resolved sensing to studying nanoscale fluid-solid
interface phenomena.
\\ ( http://arxiv.org/abs/1512.08336 ,  2447kb)
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\\
arXiv:1512.08359
Date: Mon, 28 Dec 2015 09:43:58 GMT   (3643kb,D)

Title: A discussion of $Bl$ conservation on a two dimensional magnetic field
  plane in watt balances
Authors: Shisong Li, Wei Zhao, Songling Huang
Categories: physics.class-ph
Comments: 5pages, 6 figures, submitted to MST
\\
  The watt balance is an experiment being pursued in national metrology
institutes for precision determination of the Planck constant $h$. In watt
balances, the $1/r$ magnetic field, expected to generate a geometrical factor
$Bl$ independent to any coil horizontal displacement, can be created by a
strict two dimensional, symmetric (horizontal $r$ and vertical $z$)
construction of the magnet system. In this paper, we present an analytical
understanding of magnetic field distribution when the $r$ symmetry of the
magnet is broken and the establishment of the $Bl$ conservation is shown. By
using either Gauss's law on magnetism with monopoles or conformal
transformations, we extend the $Bl$ conservation to arbitrary two dimensional
magnetic planes where the vertical magnetic field component equals zero. The
generalized $Bl$ conservation allows a relaxed physical alignment criteria for
watt balance magnet systems.
\\ ( http://arxiv.org/abs/1512.08359 ,  3643kb)
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\\
arXiv:1512.08361
Date: Mon, 28 Dec 2015 10:03:51 GMT   (1842kb)

Title: Advanced switching schemes in a Stark decelerator
Authors: Dongdong Zhang, Nicolas Vanhecke and Gerard Meijer
Categories: physics.chem-ph
\\
  We revisit the operation of the Stark decelerator and present a new,
optimized operation scheme, which substantially improves the efficiency of the
decelerator at both low and high final velocities, relevant for trapping
experiments and collision experiments, respectively. Both experimental and
simulation results show that this new mode of operation outperforms the schemes
which have hitherto been in use. This new mode of operation could potentially
be extended to other deceleration techniques.
\\ ( http://arxiv.org/abs/1512.08361 ,  1842kb)
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\\
arXiv:1512.08371
Date: Mon, 28 Dec 2015 10:57:10 GMT   (1973kb)

Title: Low-voltage coherent electron imaging based on a single-atom electron
Authors: Wei-Tse Chang, Chun-Yueh Lin, Wei-Hao Hsu, Mu-Tung Chang, Yi-Sheng
  Chen, En-Te Hwu, and Ing-Shouh Hwang
Categories: physics.ins-det cond-mat.mtrl-sci
\\
  It has been a general trend to develop low-voltage electron microscopes due
to their high imaging contrast of the sample and low radiation damage.
Atom-resolved transmission electron microscopes with voltages as low as 15-40
kV have been demonstrated. However, achieving atomic resolution at voltages
lower than 10 kV is extremely difficult. An alternative approach is coherent
imaging or phase retrieval imaging, which requires a sufficiently coherent
source and an adequately small detection area on the sample as well as the
detection of high-angle diffracted patterns with a sufficient resolution. In
this work, we propose several transmission-type schemes to achieve coherent
imaging of thin materials (less than 5 nm thick) with atomic resolution at
voltages lower than 10 kV. Experimental schemes of both lens-less and
lens-containing designs are presented and the advantages and challenges of
these schemes are discussed. Preliminary results based on a highly coherent
single-atom electron source are presented. The image plate is designed to be
retractable to record the transmission patterns at different positions along
the beam propagation direction. In addition, reflection-type coherent electron
imaging schemes are also proposed as novel methods for characterizing surface
atomic and electronic structures of materials.
\\ ( http://arxiv.org/abs/1512.08371 ,  1973kb)
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\\
arXiv:1512.08380
Date: Mon, 28 Dec 2015 11:39:29 GMT   (617kb)

Title: Large Acceptance Spectrometers for Invariant Mass Spectroscopy of Exotic
  Nuclei and Future Development
Authors: T. Nakamura, Y. Kondo
Categories: physics.ins-det nucl-ex
Comments: EMIS-2015 Conference Proceedings, submitted to NIMB
\\
  Large acceptance spectrometers at in-flight RI separators have played
significant roles in investigating the structure of exotic nuclei. Such
spectrometers are in particular useful for probing unbound states of exotic
nuclei, using invariant mass spectroscopy with reactions at intermediate and
high energies. We discuss here the key characteristic features of such
spectrometers, by introducing the recently commissioned SAMURAI facility at the
RIBF, RIKEN. We also explore the issue of cross talk in the detection of
multiple neutrons, which has become crucial for exploring further unbound
states and nuclei beyond the neutron drip line. Finally we discuss future
perspectives for large acceptance spectrometers at the new-generation RI-beam
facilities.
\\ ( http://arxiv.org/abs/1512.08380 ,  617kb)
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\\
arXiv:1512.08399
Date: Mon, 28 Dec 2015 13:01:39 GMT   (207kb)

Title: X-ray spectroscopy around the pile-up region
Authors: Gaurav Sharma, Deepak Swami, Basu Kumar, Nitin Kumar Puri and Tapan
  Nandi
Categories: physics.ins-det physics.atom-ph
\\
  We report a pile-up rejection technique based on X-ray absorption concept of
Beer-Lambert law for measuring true events in the pile-up region. We have
detected a four orders times weaker peak in the pile-up region. This technique
also enables one to resolve the weak peaks adjacent to an intense peak provided
the latter lies in the lower energy side, and the peaks are at least
theoretically resolvable by the detector used. We have resolved such peaks by
reducing the intensity ratios in our experiment. The technique allows us to
obtain the actual intensities of the observed peaks to have been measured
without any attenuator. The possible applications of this technique can be to
study the physics of two electron one-photon transition as well as the
properties of projectile-like or target-like ions.
\\ ( http://arxiv.org/abs/1512.08399 ,  207kb)
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\\
arXiv:1512.08415
Date: Mon, 28 Dec 2015 14:03:39 GMT   (4772kb,D)

Title: Magneto-electronic and optical properties of non-uniform graphene
  nanoribbons
Authors: Hsien-Ching Chung, Yu-Tsung Lin, Shih-Yang Lin, Ching-Hong Ho,
  Cheng-Peng Chang, Ming-Fa Lin
Categories: physics.comp-ph cond-mat.mtrl-sci
Comments: arXiv admin note: substantial text overlap with arXiv:1510.01889
\\
  Non-uniform bilayer graphene nanoribbons exhibit the rich magnetic
quantizations. Electronic properties are determined by the competitions among
the magnetic quantization, lateral confinement, and stacking configuration.
Four categories of magneto-electronic structures are presented, namely the
monolayer-like, bilayer-like, coexistent, and oscillatory quasi-Landau level
spectra. Their main features are clearly revealed in the energy dispersions,
spatial distribution of wave functions, density of states, and absorption
spectra.
\\ ( http://arxiv.org/abs/1512.08415 ,  4772kb)
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\\
arXiv:1512.08416
Date: Mon, 28 Dec 2015 14:04:55 GMT   (70kb)

Title: Simultaneous amplification and attenuation in isotropic chiral materials
Authors: Tom G. Mackay (University of Edinburgh), Akhlesh Lakhtakia
  (Pennsylvania State University)
Categories: physics.optics
\\
  The electromagnetic field phasors in an isotropic chiral material (ICM) are
superpositions of two Beltrami fields of different handedness. Application of
the Bruggeman homogenization formalism to two-component composite materials
delivers ICMs wherein Beltrami fields of one handedness attenuate whereas
Beltrami waves of the other handedness amplify. One component material is a
dissipative ICM, the other an active dielectric material.
\\ ( http://arxiv.org/abs/1512.08416 ,  70kb)
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\\
arXiv:1512.08431
Date: Mon, 28 Dec 2015 15:14:47 GMT   (1951kb,D)

Title: Coherence switching of a degenerate VECSEL for multimodality imaging
Authors: Sebastian Knitter, Changgeng Liu, Brandon Redding, Mustafa K. Khokha,
  Michael A. Choma, Hui Cao
Categories: physics.optics
\\
  We demonstrate a VECSEL (vertical external cavity surface emitting laser)
based degenerate source with an adjustable degree of spatial coherence that is
electrically pumped, mechanically compact and supports continuous-wave
emission. The laser operation can be switched between a large number of
mutually incoherent spatial modes and few-mode operation at little power loss.
This technology allows multimodality imaging, where low spatial coherence
illumination is used for traditional high-speed video-microscopy and high
spatial coherence illumination is used to extract dynamic information of flow
processes. The initial demonstration is performed on imaging embryo heart
function in Xenopus, which is an important animal model for human heart
disease.
\\ ( http://arxiv.org/abs/1512.08431 ,  1951kb)
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\\
arXiv:1512.08432
Date: Mon, 28 Dec 2015 15:15:04 GMT   (501kb)

Title: Reflection statistics of weakly disordered optical medium when its mean
  refractive index is different from an outside medium
Authors: Prabhakar Pradhan, Daniel John Park, Ilker Capoglu, Hariharan
  Subramanian, Dhwanil Damania, Lusik Cherkezyan, Allen Taflove, Vadim Backman
Categories: physics.optics
Comments: 9 pages, 2 figures
\\
  Based on the difference between mean background of an optical sample
refractive index n_0 and an outside medium, n_out, different than n_0, we study
the reflection statistics of a one-dimensional weakly disordered optical medium
with refractive index n(x)=n_0+dn(x). Considering dn(x) as color noise with the
exponential spatial correlation decay length l_c and k as the incident wave
vector, our results show that for the small correlation length limit, i.e.
k*l_c<1, the average value of reflectance, r, follows a form that is similar to
that of the matched refractive-index case n_0=n_out, i.e., <r(dn, lc)>
proportional to <dn^2>l_c. However, the standard deviation of r is proven to be
std(r(dn,l_c)) proportional to sqrt(<dn^2>l_c), which is different from the
matched case. Applications to light scattering from layered media and
biological cells are discussed
\\ ( http://arxiv.org/abs/1512.08432 ,  501kb)
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\\
arXiv:1512.08445
Date: Tue, 22 Dec 2015 20:00:49 GMT   (1422kb)

Title: Topology Optimization of Turbulent Fluid Flow with a Sensitive Porosity
  Adjoint Method (SPAM)
Authors: B. Philippi and Y. Jin
Categories: physics.flu-dyn math.OC
Comments: 21 pages, 8 figures
\\
  A sensitive porosity adjoint method (SPAM) for optimizing the topology of
fluid machines has been proposed. A sensitivity function with respect to the
porosity has been developed. In the first step of the optimization process,
porous media are introduced into the flow regime according to the sensitivity
function. Then the optimized porous media are transformed to solid walls. The
turbulent flow in porous media is accounted for by a modified eddy-viscosity
based turbulence model. Its influence on the adjoint equations is nevertheless
neglected, which refers to the so called frozen turbulence assumption. A test
case of application in terms of the turbulent rough wall channel flow shows
that a considerable reduction of the objective function can be obtained by this
method. The transformation from porous media to solid walls may have important
effect on the optimization results.
\\ ( http://arxiv.org/abs/1512.08445 ,  1422kb)
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\\
arXiv:1512.08481
Date: Mon, 28 Dec 2015 18:58:02 GMT   (656kb)

Title: Fiber Bragg Grating (FBG) sensors as flatness and mechanical stretching
  sensors
Authors: D. Abbaneo, M. Abbas, M. Abbrescia, A.A. Abdelalim, M. Abi Akl, O.
  Aboamer, D. Acosta, A. Ahmad, W. Ahmed, W. Ahmed, A. Aleksandrov, R. Aly, P.
  Altieri, C. Asawatangtrakuldee, P. Aspell, Y. Assran, I. Awan, S. Bally, Y.
  Ban, S. Banerjee, V. Barashko, P. Barria, G. Bencze, N. Beni, L. Benussi
  (Corresponding Author), V. Bhopatkar, S. Bianco, J. Bos, O. Bouhali, A.
  Braghieri, S. Braibant, S. Buontempo, C. Calabria, M. Caponero, C. Caputo, F.
  Cassese, A. Castaneda, S. Cauwenbergh, F.R. Cavallo, A. Celik, M. Choi, S.
  Choi, J. Christiansen, A. Cimmino, S. Colafranceschi, A. Colaleo, A. Conde
  Garcia, S. Czellar, M.M. Dabrowski, G. De Lentdecker, R. De Oliveira, G. de
  Robertis, S. Dildick, B. Dorney, W. Elmetenawee, G. Endroczi, F. Errico, A.
  Fenyvesi, S. Ferry, I. Furic, P. Giacomelli, V. Golovtsov, L. Guiducci, F.
  Guilloux, A. Gutierrez, R.M. Hadjiiska, A. Hassan, J. Hauser, K. Hoepfner, M.
  Hohlmann, H. Hoorani, P. Iaydjiev, Y.G. Jeng, T. Kamon, P. Karchin, A.
  Korytov, S. Krutelyov, A. Kumar, H. Kim, J. Lee, T. Lenzi, L. Litov, F.
  Loddo, A. Madorsky, T. Maerschalk, M. Maggi, A. Magnani, P.K. Mal, K. Mandal,
  A. Marchioro, A. Marinov, R. Masod, N. Majumdar, J.A. Merlin, G.
  Mitselmakher, A.K. Mohanty, S. Muhammad, A. Mohapatra, J. Molnar, S.
  Mukhopadhyay, M. Naimuddin, S. Nuzzo, E. Oliveri, L.M. Pant, P. Paolucci, I.
  Park, G. Passeggio, L. Passamonti, B. Pavlov, B. Philipps, D. Piccolo, D.
  Pierluigi, H. Postema, A. Puig Baranac, A. Radi, R. Radogna, G. Raffone, A.
  Ranieri, G. Rashevski, C. Riccardi, M. Rodozov, A. Rodrigues, L. Ropelewski,
  S. RoyChowdhury, A. Russo, G. Ryu, M.S. Ryu, A. Safonov, S. Salva, G.
  Saviano, A. Sharma, A. Sharma, R. Sharma, A.H. Shah, M. Shopova, J. Sturdy,
  G. Sultanov, S.K. Swain, Z. Szillasi, A. Tatarinov, T. Tuuva, M. Tytgat, I.
  Vai, M. Van Stenis, R. Venditti, E. Verhagen, P. Verwilligen, P. Vitulo, S.
  Volkov, A. Vorobyev, D. Wang, M. Wang, U. Yang, Y. Yang, R. Yonamine, N.
  Zaganidis, F. Zenoni, A. Zhang
Categories: physics.ins-det
Comments: Two pages, one figure. Presented by Luigi Benussi (corresponding
  author) to Elba 2015 conference
Report-no: Frascati Preprint INFN-15-09/LNF
\\
  A novel approach which uses Fibre Bragg Grating (FBG) sensors has been
utilised to assess and monitor the flatness of Gaseous Electron Multipliers
(GEM) foils. The setup layout and preliminary results are presented.
\\ ( http://arxiv.org/abs/1512.08481 ,  656kb)
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\\
arXiv:1512.08504
Date: Sun, 20 Dec 2015 21:39:52 GMT   (649kb)

Title: X-ray laser pulses from solids
Authors: Boris I. Ivlev
Categories: physics.gen-ph cond-mat.mtrl-sci
\\
  In experiments on irradiation of metal surfaces by ions of keV energy, X-ray
laser radiation was observed despite population inversion was unexpected. The
radiation continued after the bombarding by ions was switched off. In this
paper unusual properties of that X-ray radiation are analysed. Anomalous states
are formed inside the metal. These states are associated with a narrow
potential well created by the local reduction of zero point electromagnetic
energy. This reminds the van der Waals potential well. States in the well are
long-living which results in population inversion and the subsequent laser
generation observed.
\\ ( http://arxiv.org/abs/1512.08504 ,  649kb)
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\\
arXiv:1512.08511
Date: Fri, 11 Dec 2015 11:22:06 GMT   (4703kb)

Title: Development of Virtual Morphometric Globes Using Blender
Authors: I. V. Florinsky, S. V. Filippov
Categories: physics.geo-ph astro-ph.EP
Comments: 14 pages, 7 figures
ACM-class: J.2; I.3.7
\\
  Virtual globes - programs implementing interactive three-dimensional (3D)
models of planets - are increasingly used in geosciences. Global morphometric
models can be useful for tectonic and planetary studies. We describe the
development of the first testing version of the system of virtual morphometric
globes for the Earth, Mars, and the Moon. As the initial data, we used three
15'-gridded global digital elevation models (DEMs) extracted from SRTM30_PLUS,
the Mars Orbiter Laser Altimeter, and the Lunar Orbiter Laser Altimeter gridded
archives. For three planetary bodies, we derived global digital models and maps
of several morphometric attributes (i.e., horizontal curvature, vertical
curvature, minimal curvature, maximal curvature, and catchment area). To
develop the system, we used Blender, the open-source software for 3D modeling
and visualization. First, a 3D sphere model was generated. Second, the global
morphometric maps as textures were imposed to the sphere surface. Finally, the
real-time 3D graphics Blender engine was used to implement globe rotation and
zooming. The testing of the developed system demonstrated its good performance.
Morphometric globes clearly represent peculiarities of planetary topography,
according to the physical and mathematical sense of a particular morphometric
variable.
\\ ( http://arxiv.org/abs/1512.08511 ,  4703kb)
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arXiv:1512.07236 (*cross-listing*)
Date: Tue, 22 Dec 2015 20:36:38 GMT   (257kb,D)

Title: Generalized canonical purification for density matrix minimization
Authors: Lionel A. Truflandier, Mamy R. Dianzinga, David R. Bowler
Categories: math-ph math.MP physics.chem-ph physics.comp-ph
Comments: 5 pages, 2 figures
\\
  A Lagrangian formulation for the constrained search for the $N$-representable
one-particle density matrix based on the McWeeny idempotency error minimization
is proposed, which converges systematically to the ground state. A closed form
of the canonical purification is derived for which no \textit{a posteriori}
adjustement on the trace of the density matrix is needed. The relationship with
comparable methods are discussed, showing their possible generalization through
the \textit{hole-particle} duality. The appealing simplicity of this
\textit{self-consistent} recursion relation along with its low computational
complexity could prove useful as an alternative to diagonalization in solving
dense and sparse matrix eigenvalue problems.
\\ ( http://arxiv.org/abs/1512.07236 ,  257kb)
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\\
arXiv:1512.07933 (*cross-listing*)
Date: Thu, 24 Dec 2015 23:54:13 GMT   (6074kb,D)

Title: Deterministic separation of arbitrary photon pair states in integrated
  quantum circuits
Authors: Ryan P. Marchildon and Amr S. Helmy
Categories: quant-ph physics.optics
Comments: 11 pages, 14 figures; to be published in Laser & Photonics Reviews
DOI: 10.1002/lpor.201500133
\\
  Entangled photon pairs generated within integrated devices must often be
spatially separated for their subsequent manipulation in quantum circuits.
Separation that is both deterministic and universal can in principle be
achieved through anti-coalescent two-photon quantum interference. However, such
interference-facilitated pair separation (IFPS) has not been extensively
studied in the integrated setting, where the strong polarization and wavelength
dependencies of integrated couplers -- as opposed to bulk-optics beamsplitters
-- can have important implications for performance beyond the identical-photon
regime. This paper provides a detailed review of IFPS and examines how these
dependencies impact separation fidelity and interference visibility. Focus is
given to IFPS mediated by an integrated directional coupler. The analysis
applies equally to both on-chip and in-fiber implementations, and can be
expanded to other coupler architectures such as multimode interferometers. When
coupler dispersion is present, the separation performance can depend on photon
bandwidth, spectral entanglement, and the linearity of the dispersion. Under
appropriate conditions, reduction in the separation fidelity due to loss of
non-classical interference can be perfectly compensated for by classical
wavelength demultiplexing effects. This work informs the design as well as the
performance assessment of circuits for achieving universal photon pair
separation for states with tunable arbitrary properties.
\\ ( http://arxiv.org/abs/1512.07933 ,  6074kb)
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\\
arXiv:1512.07947 (*cross-listing*)
Date: Fri, 25 Dec 2015 02:58:53 GMT   (3899kb,D)

Title: Sparse Reconstruction of Compressive Sensing MRI using Cross-Domain
  Stochastically Fully Connected Conditional Random Fields
Authors: Edward Li, Farzad Khalvati, Mohammad Javad Shafiee, Masoom A. Haider,
  Alexander Wong
Categories: cs.CV physics.med-ph stat.ME
Comments: 9 pages
\\
  Magnetic Resonance Imaging (MRI) is a crucial medical imaging technology for
the screening and diagnosis of frequently occurring cancers. However image
quality may suffer by long acquisition times for MRIs due to patient motion, as
well as result in great patient discomfort. Reducing MRI acquisition time can
reduce patient discomfort and as a result reduces motion artifacts from the
acquisition process. Compressive sensing strategies, when applied to MRI, have
been demonstrated to be effective at decreasing acquisition times significantly
by sparsely sampling the \emph{k}-space during the acquisition process.
However, such a strategy requires advanced reconstruction algorithms to produce
high quality and reliable images from compressive sensing MRI. This paper
proposes a new reconstruction approach based on cross-domain stochastically
fully connected conditional random fields (CD-SFCRF) for compressive sensing
MRI. The CD-SFCRF introduces constraints in both \emph{k}-space and spatial
domains within a stochastically fully connected graphical model to produce
improved MRI reconstruction. Experimental results using T2-weighted (T2w)
imaging and diffusion-weighted imaging (DWI) of the prostate show strong
performance in preserving fine details and tissue structures in the
reconstructed images when compared to other tested methods even at low sampling
rates.
\\ ( http://arxiv.org/abs/1512.07947 ,  3899kb)
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\\
arXiv:1512.07949 (*cross-listing*)
Date: Fri, 25 Dec 2015 03:25:36 GMT   (7715kb)

Title: On Sun-to-Earth Propagation of Coronal Mass Ejections: 2. Slow Events
  and Comparison with Others
Authors: Ying D. Liu, Huidong Hu, Chi Wang, Janet G. Luhmann, John D.
  Richardson, Zhongwei Yang, and Rui Wang
Categories: astro-ph.SR physics.space-ph
Comments: 37 pages, 13 figures, accepted for publication in ApJ Supplement
\\
  As a follow-up study on Sun-to-Earth propagation of fast coronal mass
ejections (CMEs), we examine the Sun-to-Earth characteristics of slow CMEs
combining heliospheric imaging and in situ observations. Three events of
particular interest, the 2010 June 16, 2011 March 25 and 2012 September 25
CMEs, are selected for this study. We compare slow CMEs with fast and
intermediate-speed events, and obtain key results complementing the attempt of
\citet{liu13} to create a general picture of CME Sun-to-Earth propagation: (1)
the Sun-to-Earth propagation of a typical slow CME can be approximately
described by two phases, a gradual acceleration out to about 20-30 solar radii,
followed by a nearly invariant speed around the average solar wind level, (2)
comparison between different types of CMEs indicates that faster CMEs tend to
accelerate and decelerate more rapidly and have shorter cessation distances for
the acceleration and deceleration, (3) both intermediate-speed and slow CMEs
would have a speed comparable to the average solar wind level before reaching 1
AU, (4) slow CMEs have a high potential to interact with other solar wind
structures in the Sun-Earth space due to their slow motion, providing critical
ingredients to enhance space weather, and (5) the slow CMEs studied here lack
strong magnetic fields at the Earth but tend to preserve a flux-rope structure
with axis generally perpendicular to the radial direction from the Sun. We also
suggest a "best" strategy for the application of a triangulation concept in
determining CME Sun-to-Earth kinematics, which helps to clarify confusions
about CME geometry assumptions in the triangulation and to improve CME analysis
and observations.
\\ ( http://arxiv.org/abs/1512.07949 ,  7715kb)
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\\
arXiv:1512.07966 (*cross-listing*)
Date: Fri, 25 Dec 2015 06:44:00 GMT   (390kb)

Title: Campaigning in Heterogeneous Social Networks: Optimal Control of SI
  Information Epidemics
Authors: Kundan Kandhway, Joy Kuri
Categories: cs.SI cs.SY math.OC physics.soc-ph
Comments: 14 pages, 10 figures. Published version can be accessed at
  http://dx.doi.org/10.1109/TNET.2014.2361801
DOI: 10.1109/TNET.2014.2361801
\\
  We study the optimal control problem of maximizing the spread of an
information epidemic on a social network. Information propagation is modeled as
a Susceptible-Infected (SI) process and the campaign budget is fixed. Direct
recruitment and word-of-mouth incentives are the two strategies to accelerate
information spreading (controls). We allow for multiple controls depending on
the degree of the nodes/individuals. The solution optimally allocates the
scarce resource over the campaign duration and the degree class groups. We
study the impact of the degree distribution of the network on the controls and
present results for Erdos-Renyi and scale free networks. Results show that more
resource is allocated to high degree nodes in the case of scale free networks
but medium degree nodes in the case of Erdos-Renyi networks. We study the
effects of various model parameters on the optimal strategy and quantify the
improvement offered by the optimal strategy over the static and bang-bang
control strategies. The effect of the time varying spreading rate on the
controls is explored as the interest level of the population in the subject of
the campaign may change over time. We show the existence of a solution to the
formulated optimal control problem, which has non-linear isoperimetric
constraints, using novel techniques that is general and can be used in other
similar optimal control problems. This work may be of interest to political,
social awareness, or crowdfunding campaigners and product marketing managers,
and with some modifications may be used for mitigating biological epidemics.
\\ ( http://arxiv.org/abs/1512.07966 ,  390kb)
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\\
arXiv:1512.07976 (*cross-listing*)
Date: Fri, 25 Dec 2015 08:11:32 GMT   (11kb)

Title: Reflections on Zeilinger-Brukner information interpretation of quantum
  mechanics
Authors: Andrei Khrennikov
Categories: quant-ph physics.hist-ph physics.pop-ph
\\
  In this short review I present my personal reflections on Zeilinger-Brukner
information interpretation of quantum mechanics (QM). In general this
interpretation is very attractive for me. However, its rigid coupling to the
notion of irreducible quantum randomness is a very complicated issue which I
plan to enlighten in more detail. This note may be useful for general public
interested in quantum foundations, especially because I try to analyze
essentials of the information interpretation critically (i.e., not just
emphasizing its advantages as it is commonly done). This review is written in
non-physicist friendly manner. Experts actively exploring this interpretation
may be interested as well - in comments of "an external observer" who have been
monitoring development of this approach to QM during last 18 years. The last
part of this review is devoted to the general methodology of science with
references to views of de Finetti, Wigner, and Peres.
\\ ( http://arxiv.org/abs/1512.07976 ,  11kb)
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\\
arXiv:1512.08010 (*cross-listing*)
Date: Fri, 25 Dec 2015 15:32:30 GMT   (67kb)

Title: A hierarchy of Poisson brackets
Authors: Michal Pavelka, Vaclav Klika, Ogul Esen, Miroslav Grmela
Categories: math-ph math.MP physics.flu-dyn
Comments: 50 pages, 1 figure, Submitted to Physica D in August 2015
\\
  The vector field generating reversible time evolution of macroscopic systems
involves two ingredients: gradient of a potential (a covector) and a degenerate
Poisson structure transforming the covector into a vector. The Poisson
structure is conveniently expressed in Poisson brackets, its degeneracy in
their Casimirs (i.e. potentials whose gradients produce no vector field). In
this paper we investigate in detail hierarchies of Poisson brackets, together
with their Casimirs, that arise in passages from more to less detailed (i.e.
more macroscopic) descriptions. In particular, we investigate the passage from
mechanics of particles (in its Liouville representation) to the reversible
kinetic theory and the passage from the reversible kinetic theory to the
reversible fluid mechanics. From the physical point of view, the investigation
includes binary mixtures and two-point formulations suitable for describing
turbulent flows. From the mathematical point of view, we reveal the Lie algebra
structure involved in the passage from the Liouville to the one-point and
two-point Boltzmann descriptions.
\\ ( http://arxiv.org/abs/1512.08010 ,  67kb)
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\\
arXiv:1512.08085 (*cross-listing*)
Date: Sat, 26 Dec 2015 07:45:55 GMT   (2453kb)

Title: Symbiotic Cell Differentiation and Cooperative Growth for the Emergence
  of Multicellularity
Authors: Jumpei Yamagishi, Nen Saito, Kunihiko Kaneko
Categories: q-bio.CB physics.bio-ph q-bio.PE
Comments: 9 pages, 6 figures
\\
  The origin of multicellularity is a fundamental open question in biology. For
multicellular organisms to evolve from an aggregate of unicellular organisms,
cells with an identical genotype must first differentiate into several types.
Second, this aggregate of distinct cell types should show better growth than
that of an isolated cell in the environment. Third, this cell aggregate should
show robustness in the number distribution of differentiated cell types. To
reveal how an ensemble of primitive cells achieves these conditions, we
developed a dynamical-systems model of cells consisting of chemical components
with intracellular catalytic reaction dynamics. The reactions convert external
nutrients to internal components for cellular growth, and the divided cells
interact through chemical diffusion. We found that cells sharing an identical
catalytic network spontaneously differentiate induced by cell-cell
interactions, and then achieve cooperative division of labor, the mutual use of
products among differentiated cell types, enabling a higher growth rate than
that in the unicellular case. This symbiotic differentiation emerged for a
class of reaction networks under the condition of nutrient limitation and
strong cell-cell interactions. Then, robustness in the cell type distribution
was achieved, while instability of collective growth sometimes emerged even
among the cooperative cells when the internal reserves of chemical products is
dominant. The simplicity and generality of the present mechanism suggests that
evolution to multicellularity is a natural consequence of interacting cells
with limited resources, being consistent with the behaviors and forms of
several extant primitive forms of multicellularity, such as certain bacteria.
\\ ( http://arxiv.org/abs/1512.08085 ,  2453kb)
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\\
arXiv:1512.08116 (*cross-listing*)
Date: Sat, 26 Dec 2015 14:06:33 GMT   (1609kb)

Title: Quantum simulation of 2d topological physics using
  orbital-angular-momentum-carrying photons in a 1d array of cavities
Authors: Xi-Wang Luo, Xingxiang Zhou, Chuan-Feng Li, Jin-Shi Xu, Guang-Can Guo
  and Zheng-Wei Zhou
Categories: quant-ph cond-mat.mes-hall physics.optics
Comments: 8 pages, 6 figures
Journal-ref: Nature Communications 6: 7704 (2015)
\\
  Orbital angular momentum (OAM) of light is a fundamental optical degree of
freedom that has recently motivated much exciting research in diverse fields
ranging from optical communication to quantum information. We show for the
first time that it is also a unique and valuable resource for quantum
simulation, by demonstrating theoretically how \emph{2d} topological physics
can be simulated in a \emph{1d} array of optical cavities using OAM-carrying
photons. Remarkably, this newly discovered application of OAM states not only
reduces required physical resources but also increases feasible scale of
simulation. By showing how important topics such as edge-state transport and
topological phase transition can be studied in a small simulator with just a
few cavities ready for immediate experimental exploration, we demonstrate the
prospect of photonic OAM for quantum simulation which can have a significant
impact on the research of topological physics.
\\ ( http://arxiv.org/abs/1512.08116 ,  1609kb)
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\\
arXiv:1512.08131 (*cross-listing*)
Date: Sat, 26 Dec 2015 18:30:34 GMT   (890kb)

Title: Pressure-anisotropy-driven microturbulence and magnetic-field evolution
  in shearing, collisionless plasma
Authors: S. Melville (Harvard), A. A. Schekochihin (Oxford), M. W. Kunz
  (Princeton)
Categories: astro-ph.HE astro-ph.CO nlin.CD physics.plasm-ph physics.space-ph
Comments: MNRAS-style latex, 21 pages, 37 figures, submitted to MNRAS
\\
  The nonlinear state of a high-beta collisionless plasma is investigated when
an imposed linear shear amplifies or diminishes a uniform magnetic field,
driving pressure anisotropies and hence firehose/mirror instabilities. The
evolution of the resulting microscale turbulence is considered when the shear
is switched off or reversed after one shear time (mimicking local behaviour of
a macroscopic flow), so a new macroscale configuration is superimposed on the
microscale state left behind by the previous one. There is a threshold value of
plasma beta: when $\beta\ll\Omega/S$ (ion cyclotron frequency/shear rate), the
emergence of firehose/mirror fluctuations driven unstable by shear and their
disappearance when the shear is removed/reversed are quasi-instantaneous
compared to the shear time, viz., the decay time of these fluctuations is
$\sim\beta/\Omega \ll 1/S$ (this result follows from the free decay of the
fluctuations being constrained by the same marginal-stability thresholds as
their growth). In contrast, when $\beta\gtrsim\Omega/S$ ("ultra-high" beta),
the old microscale state can only be removed on the shear timescale. In this
regime, driven firehose fluctuations grow secularly to order-unity amplitudes,
compensating for the decay of the mean field and so pinning pressure anisotropy
at marginal stability with no appreciable scattering of particles---which is
unlike what happens at moderate $\beta$. When the shear reverses, the shearing
away of this firehose turbulence compensates for the increase in the mean field
and thus prevents growth of the pressure anisotropy, stopping the system from
going mirror-unstable. Therefore, at ultra-high beta, the system stays close to
the firehose threshold, the mirror instability is largely suppressed, while the
mean magnetic energy barely changes at all. Implications for plasma dynamo and
thus the origin of cosmic magnetism are discussed.
\\ ( http://arxiv.org/abs/1512.08131 ,  890kb)
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\\
arXiv:1512.08171 (*cross-listing*)
Date: Sun, 27 Dec 2015 05:27:52 GMT   (237kb)

Title: Waves in vertically inhomogeneous dissipative atmosphere
Authors: I.S. Dmitrienko and G.V. Rudenko
Categories: astro-ph.EP physics.ao-ph
Comments: 48 pages, 8 figures
MSC-class: 86-08
ACM-class: J.2
\\
  A method of construction of solution for acoustic-gravity waves (AGW) above a
wave source, taking dissipation throughout the atmosphere into account
(Dissipative Solution above Source, DSAS), is proposed. The method is to
combine three solutions for three parts of the atmosphere: an analytical
solution for the upper isothermal part and numerical solutions for the real
non-isothermal dissipative atmosphere in the middle part and for the real
non-isothermal small dissipation atmosphere in the lower one. In this paper the
method has been carried out for the atmosphere with thermal conductivity but
without viscosity. The heights of strong dissipation and the total absorption
index in the regions of weak and average dissipation are found. For internal
gravity waves the results of test calculations for an isothermal atmosphere and
calculations for a real non-isothermal atmosphere are shown in graphical form.
An algorithm and appropriate code to calculate DSAS, taking dissipation due to
finite thermal conductivity into account throughout the atmosphere, are
developed. The results of test DSAS calculations for an everywhere isothermal
atmosphere are given. The calculation results for DSAS for the real
non-isothermal atmosphere are also presented. A method for constructing of the
2x2 Green's matrix fully taking dissipation into account and allowing to find
disturbance from some source of AGW in the atmosphere is proposed.
\\ ( http://arxiv.org/abs/1512.08171 ,  237kb)
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\\
arXiv:1512.08174 (*cross-listing*)
Date: Sun, 27 Dec 2015 05:42:48 GMT   (336kb)

Title: Waveguide gravity disturbances in vertically inhomogeneous dissipative
  atmosphere
Authors: G. V. Rudenko and I.S. Dmitrienko
Categories: astro-ph.EP physics.ao-ph
Comments: 32 pages, 17 figures
MSC-class: 86-08
ACM-class: J.2
\\
  Trapped atmosphere waves, such as IGW waveguide modes and Lamb modes, are
described using dissipative solution above source (DSAS) (Dmitrienko and
Rudenko, 2016). Accordingly this description, the modes are disturbances
penetrating without limit in the upper atmosphere and dissipating their energy
throughout the atmosphere; leakage from a trapping region to the upper
atmosphere is taken in consideration. The DSAS results are compared to those
based on both accurate and WKB approximated dissipationless equations. It is
shown that the spatial and frequency characteristics of modes in the upper
atmosphere calculated by any of the methods are close to each other and are in
good agreement with the observed characteristics of traveling ionospheric
disturbances.
\\ ( http://arxiv.org/abs/1512.08174 ,  336kb)
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\\
arXiv:1512.08202 (*cross-listing*)
Date: Sun, 27 Dec 2015 11:11:27 GMT   (417kb,D)

Title: A non-conventional neutrino beamline for the measurement of the electron
  neutrino cross section
Authors: A. Berra, S. Cecchini, F. Cindolo, C. Jollet, A. Longhin, L. Ludovici,
  G. Mandrioli, N. Mauri, A. Meregaglia, A. Paoloni, L. Pasqualini, L.
  Patrizii, F. Pupilli, M. Pozzato, M. Prest, G. Sirri, F. Terranova, E.
  Vallazza, L. Votano
Categories: hep-ex hep-ph physics.ins-det
Comments: 10 pages, 2 figures; to appear in the Proceedings of NuFact15
\\
  Absolute neutrino cross section measurements at the GeV scale are ultimately
limited by the knowledge of the initial $\nu$ flux. In order to evade such
limitation and reach the accuracy that is needed for precision oscillation
physics ($\sim 1$%), substantial advances in flux measurement techniques are
requested. We discuss here the possibility of instrumenting the decay tunnel to
identify large-angle positrons and monitor $\nu_e$ production from $K^+
\rightarrow e^+ \nu_e \pi^0$ decays. This non conventional technique opens up
opportunities to measure the $\nu_e$ CC cross section at the per cent level in
the energy range of interest for DUNE/HK. We discuss the progress in the
simulation of the facility (beamline and instrumentation) and the ongoing R&D.
\\ ( http://arxiv.org/abs/1512.08202 ,  417kb)
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\\
arXiv:1512.08257 (*cross-listing*)
Date: Sun, 27 Dec 2015 18:25:53 GMT   (285kb)

Title: The Stability of the Vacuum Polarization Surrounding a Charged Particle
Authors: F. J. Himpsel
Categories: quant-ph physics.atom-ph
Comments: 11 pages, 10 figures
\\
  The internal stability of the electron has been debated for a century at both
the classical and the quantum level. Recently, a local force density balance
was established for the 1s electron in the H atom, based on the energy-momentum
tensor of the classical Dirac field. This methodology is now extended to
quantum fields by considering the force densities acting on the vacuum
polarization induced by a point charge. Such a model is applicable to any
charged particle at large distances, since the only vestige of its internal
structure is the electric Coulomb field together with the vacuum polarization
induced by it. While the polarization charge density is attracted to the point
charge, it is kept from collapsing by repulsive forces due to confinement and
degeneracy. It is shown analytically that the corresponding force densities are
balanced for every filled shell of mj states at a given angular momentum j. The
force densities are then summed over all single-electron states in the Dirac
sea and renormalized by subtracting singular terms. In leading order of alpha,
the force densities remain balanced. This result establishes a local force
balance for a prototypical manybody system.
\\ ( http://arxiv.org/abs/1512.08257 ,  285kb)
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\\
arXiv:1512.08328 (*cross-listing*)
Date: Mon, 28 Dec 2015 07:01:56 GMT   (840kb,D)

Title: Role of spatial averaging in multicellular gradient sensing
Authors: Tyler Smith, Sean Fancher, Andre Levchenko, Ilya Nemenman, and Andrew
  Mugler
Categories: q-bio.MN physics.bio-ph
Comments: 15 pages, 3 figures
\\
  Gradient sensing underlies important biological processes including
morphogenesis, polarization, and cell migration. The precision of gradient
sensing increases with the length of a detector (a cell or group of cells) in
the gradient direction, since a longer detector spans a larger range of
concentration values. Intuition from analyses of concentration sensing suggests
that precision should also increase with detector length in the direction
transverse to the gradient, since then spatial averaging should reduce the
noise. However, here we show that, unlike for concentration sensing, the
precision of gradient sensing decreases with transverse length for the simplest
gradient sensing model, local excitation--global inhibition (LEGI). The reason
is that gradient sensing ultimately relies on a subtraction of measured
concentration values. While spatial averaging indeed reduces the noise in these
measurements, which increases precision, it also reduces the covariance between
the measurements, which results in the net decrease in precision. We
demonstrate how a recently introduced gradient sensing mechanism, regional
excitation--global inhibition (REGI), overcomes this effect and recovers the
benefit of transverse averaging. Using a REGI-based model, we compute the
optimal two- and three-dimensional detector shapes, and argue that they are
consistent with the shapes of naturally occurring gradient-sensing cell
populations.
\\ ( http://arxiv.org/abs/1512.08328 ,  840kb)
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\\
arXiv:1512.08339 (*cross-listing*)
Date: Mon, 28 Dec 2015 08:00:27 GMT   (3619kb)

Title: Detecting local processing unit in drosophila brain by using network
  theory
Authors: Dongmei Shi, Chitin Shih, Yenjen Lin, Chungchuan Lo, and Annshyn
  Chiang
Categories: q-bio.NC physics.bio-ph
\\
  Community detection method in network theory was applied to the neuron
network constructed from the image overlapping between neuron pairs to detect
the Local Processing Unit (LPU) automatically in Drosophila brain. 26
communities consistent with the known LPUs, and 13 subdivisions were found.
Besides, 45 tracts were detected and could be discriminated from the LPUs by
analyzing the distribution of participation coefficient P. Furthermore, layer
structures in fan-shaped body (FB) were observed which coincided with the
images shot by the optical devices, and a total of 13 communities were proven
closely related to FB. The method proposed in this work was proven effective to
identify the LPU structure in Drosophila brain irrespectively of any subjective
aspect, and could be applied to the relevant areas extensively.
\\ ( http://arxiv.org/abs/1512.08339 ,  3619kb)
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\\
arXiv:1512.08347 (*cross-listing*)
Date: Mon, 28 Dec 2015 08:50:50 GMT   (2580kb)

Title: Communicating with sentences: A multi-word naming game model
Authors: Yang Lou, Guanrong Chen and Jianwei Hu
Categories: cs.CL physics.soc-ph
Comments: Paper(13pp,10figures) + SI(7pp,8figures)
\\
  Naming game simulates the process of naming a single object by a single word,
in which a population of communicating agents can reach global consensus
asymptotically through iteratively pair-wise conversations. In this paper, we
propose an extension of the single-word naming game, to a multi-word naming
game (MWNG), which simulates the naming game process when agents name an object
by a sentence (i.e., a series of multiple words) for describing a complex
object such as an opinion or an event. We first define several categories of
words, and then organize sentences by combining words from different word
categories. We refer to a formatted combination of several words as a pattern.
In such an MWNG, through a pair-wise conversation, it requires the hearer to
achieve consensus with the speaker with respect to both every single word in
the sentence as well as the sentence pattern, so as to guarantee the correct
meaning of the saying; otherwise, they fail reaching consensus in the
interaction. We employ three typical topologies used for the underlying
communication network, namely random-graph, small-world and scale-free
networks. We validate the model by using both conventional English language
patterns and man-made test sentence patterns in performing the MWNG. Our
simulation results show that: 1) the new sentence sharing model is an extension
of the classical lexicon sharing model; 2) the propagating, learning and
converging processes are more complicated than that in the conventional naming
game; 3) the convergence time is non-decreasing as the network becomes better
connected; 4) the agents are prone to accept short sentence patterns. These new
findings may help deepen our understanding of the human language development
from a network science perspective.
\\ ( http://arxiv.org/abs/1512.08347 ,  2580kb)
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\\
arXiv:1512.08369 (*cross-listing*)
Date: Mon, 28 Dec 2015 10:50:51 GMT   (285kb,D)

Title: Insight into the Li$_2$CO$_3$--K$_2$CO$_3$ eutectic mixture from
  classical molecular dynamics: thermodynamics, structure and dynamics
Authors: Dario Corradini, Fran\c{c}ois-Xavier Coudert, Rodolphe Vuilleumier
Categories: cond-mat.mtrl-sci physics.chem-ph physics.comp-ph
\\
  In this work, we use molecular dynamics simulations to study the
thermodynamics, structure and dynamics of the Li$_2$CO$_3$--K$_2$CO$_3$ (62:38
mol\%) eutectic mixture. We present a new classical non-polarizable force field
for this molten salt mixture, optimized using experimental and first principles
molecular dynamics simulations as reference data. This simple force field
allows efficient molecular simulations of phenomena at long timescales. We use
this optimized force field to describe the behavior of the eutectic mixture in
the 900--1100~K temperature range, at pressures between 0 and 5~GPa. After
studying the equation of state in these thermodynamic conditions, we present
molecular insight into the structure and dynamics of the melt. In particular,
we present an analysis of the temperature and pressure dependence of the
eutectic mixture's self diffusion coefficients, viscosity and ionic
conductivity.
\\ ( http://arxiv.org/abs/1512.08369 ,  285kb)
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\\
arXiv:1512.08398 (*cross-listing*)
Date: Mon, 28 Dec 2015 13:01:30 GMT   (735kb)

Title: Macroscopic dynamics of incoherent soliton ensembles: soliton-gas
  kinetics and direct numerical modeling
Authors: Francesco Carbone (CNR-IIA), Denys Dutykh (LAMA), Gennady El
Categories: nlin.PS physics.comp-ph physics.flu-dyn
Comments: 20 pages, 8 figures, 34 references. Other author's papers can be
  downloaded at http://www.denys-dutykh.com/
\\
  We undertake a detailed comparison of the results of direct numerical
simulations of the integrable soliton gas dynamics with the analytical
predictions inferred from the exact solutions of the relevant kinetic equation
for solitons. We use the KdV soliton gas as a simplest analytically accessible
model yielding major insight into the general properties of soliton gases in
integrable systems. Two model problems are considered: (i) the propagation of a
`trial' soliton through a one-component `cold' soliton gas consisting of
randomly distributed solitons of approximately the same amplitude; and (ii)
collision of two cold soliton gases of different amplitudes (soliton gas shock
tube problem) leading to the formation of an incoherend dispersive shock wave.
In both cases excellent agreement is observed between the analytical
predictions of the soliton gas kinetics and the direct numerical simulations.
Our results confirm relevance of the kinetic equation for solitons as a
quantitatively accurate model for macroscopic non-equilibrium dynamics of
incoherent soliton ensembles.
\\ ( http://arxiv.org/abs/1512.08398 ,  735kb)
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\\
arXiv:1512.08408 (*cross-listing*)
Date: Mon, 28 Dec 2015 13:29:17 GMT   (2887kb)

Title: Multiscale models and approximation algorithms for protein
  electrostatics
Authors: Jaydeep P. Bardhan and Matthew G. Knepley
Categories: math.NA physics.chem-ph q-bio.BM
Comments: 12 pages, 6 figures
\\
  Electrostatic forces play many important roles in molecular biology, but are
hard to model due to the complicated interactions between biomolecules and the
surrounding solvent, a fluid composed of water and dissolved ions. Continuum
model have been surprisingly successful for simple biological questions, but
fail for important problems such as understanding the effects of protein
mutations. In this paper we highlight the advantages of boundary-integral
methods for these problems, and our use of boundary integrals to design and
test more accurate theories. Examples include a multiscale model based on
nonlocal continuum theory, and a nonlinear boundary condition that captures
atomic-scale effects at biomolecular surfaces.
\\ ( http://arxiv.org/abs/1512.08408 ,  2887kb)
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\\
arXiv:1512.08412 (*cross-listing*)
Date: Mon, 28 Dec 2015 13:49:26 GMT   (2228kb,D)

Title: Detecting weak coupling between quantum systems with a nonequilibrium
  Fano resonance
Authors: S. Xiao and Y. Yoon and Y.-H. Lee and J. P. Bird and Y. Ochiai and N.
  Aoki and J. L. Reno and J. Fransson
Categories: cond-mat.mes-hall cond-mat.stat-mech physics.atom-ph quant-ph
Comments: 11 pages, 4 figures, submitted
\\
  A critical aspect of quantum mechanics is the nonlocal nature of the
wavefunction, a characteristic that may yield unexpected coupling of nominally
isolated systems. The capacity to detect this coupling can be vital in many
situations, especially those in which its strength is weak. In this work we
demonstrate an approach to such detection by making use of one of the most
ubiquitous of wave-interference phenomena, namely the Fano resonance. The focus
of this joint experimental and theoretical work is on demonstrating a novel
form of \textit{nonequilibrium} Fano resonance, that is very different in
nature to the usual (quasi-equilibrium) implementations of this phenomenon. The
essential idea of our approach is to exploit the strong sensitivity of the Fano
resonance to the presence of additional transmission pathways, as a means to
identify the coupling of some host system to an \textit{intruder}. Crucially,
our nonequilibrium scheme allows us to detect the presence of \textit{hidden}
components within some system, even while they remain \textit{invisible} in
near-equilibrium transport. For a proof-of-concept demonstration of this
phenomenon, we implement an electron-wave interferometer from mesoscopic
quantum point contacts. The wave-based origins of the Fano resonance imply,
however, that our scheme should be widely realizable across a variety of
physical platforms.
\\ ( http://arxiv.org/abs/1512.08412 ,  2228kb)
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\\
arXiv:1512.08455 (*cross-listing*)
Date: Mon, 28 Dec 2015 16:51:07 GMT   (4518kb)

Title: Full-scale Cascade Dynamics Prediction with a Local-First Approach
Authors: Tao Wu, Leiting Chen, Xingping Xian, Yuxiao Guo
Categories: cs.SI physics.soc-ph
\\
  Information cascades are ubiquitous in various social networking web sites.
What mechanisms drive information diffuse in the networks? How does the
structure and size of the cascades evolve in time? When and which users will
adopt a certain message? Approaching these questions can considerably deepen
our understanding about information cascades and facilitate various vital
applications, including viral marketing, rumor prevention and even link
prediction. Most previous works focus only on the final cascade size
prediction. Meanwhile, they are always cascade graph dependent methods, which
make them towards large cascades prediction and lead to the criticism that
cascades may only be predictable after they have already grown large. In this
paper, we study a fundamental problem: full-scale cascade dynamics prediction.
That is, how to predict when and which users are activated at any time point of
a cascading process. Here we propose a unified framework, FScaleCP, to solve
the problem. Given history cascades, we first model the local spreading
behaviors as a classification problem. Through data-driven learning, we
recognize the common patterns by measuring the driving mechanisms of cascade
dynamics. After that we present an intuitive asynchronous propagation method
for full-scale cascade dynamics prediction by effectively aggregating the local
spreading behaviors. Extensive experiments on social network data set suggest
that the proposed method performs noticeably better than other state-of-the-art
baselines.
\\ ( http://arxiv.org/abs/1512.08455 ,  4518kb)
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\\
arXiv:1512.08480 (*cross-listing*)
Date: Mon, 28 Dec 2015 18:46:45 GMT   (1649kb,D)

Title: Rydberg-induced optical nonlinearities from a cold atomic ensemble
  trapped inside a cavity
Authors: Rajiv Boddeda, Imam Usmani, Erwan Bimbard, Andrey Grankin, Alexei
  Ourjoumtsev, Etienne Brion and Philippe Grangier
Categories: quant-ph cond-mat.quant-gas physics.atom-ph
Comments: 8 pages, 6 figures
\\
  We experimentally characterize the optical nonlinear response of a cold
atomic medium placed inside an optical cavity, and excited to Rydberg states.
The excitation to S and D Rydberg levels is carried out via a two-photon
transition in an EIT (electromagnetically induced transparency) configuration,
with a weak (red) probe beam on the lower transition, and a strong (blue)
coupling beam on the upper transition. The observed optical nonlinearities
induced by S states for the probe beam can be explained using a semi-classical
model with van der Waals' interactions. For the D states, it appears necessary
to take into account a dynamical decay of Rydberg excitations into a long-lived
dark state. We show that the measured nonlinearities can be explained by using
a Rydberg bubble model with a dynamical decay.
\\ ( http://arxiv.org/abs/1512.08480 ,  1649kb)
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\\
arXiv:1512.08487 (*cross-listing*)
Date: Mon, 28 Dec 2015 19:39:57 GMT   (9kb)

Title: Monotonicity of the period of a non linear oscillator
Authors: R.D. Benguria, M.C. Depassier and M. Loss
Categories: math.CA physics.class-ph
Comments: 9 pages
MSC-class: 34B15, 34C23, 34C25
\\
  We revisit the problem of monotonicity of the period function for the
differential equation $u"-u+u^p=0$ and give a simple proof of recent results of
Miyamoto and Yagasaki.
\\ ( http://arxiv.org/abs/1512.08487 ,  9kb)
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\\
arXiv:1512.08495 (*cross-listing*)
Date: Mon, 28 Dec 2015 20:11:58 GMT   (79kb)

Title: The Longevity of Lava Dome Eruptions
Authors: Robert L. Wolpert, Sarah E. Ogburn, Eliza S. Calder
Categories: stat.AP physics.geo-ph
Comments: 17 pages, 4 figures, 3 tables
\\
  Understanding the duration of past, on-going and future volcanic eruptions is
an important scientific goal and a key societal need. We present a new
methodology for forecasting the duration of on-going and future lava dome
eruptions based on a database (DomeHaz) recently compiled by the authors. The
database includes duration and composition for 177 such eruptions, with
"eruption" defined as the period encompassing individual episodes of dome
growth along with associated quiescent periods during which extrusion pauses
but unrest continues. In a key finding we show that probability distributions
for dome eruption durations are both heavy-tailed and composition-dependent. We
construct Objective Bayes statistical models featuring heavy-tailed Generalized
Pareto distributions with composition-specific parameters to make forecasts
about the durations of new and on-going eruptions that depend on both eruption
duration-to-date and composition. Our Bayesian predictive distributions reflect
both uncertainty about model parameter values (epistemic uncertainty) and the
natural variability of the geologic processes (aleatoric uncertainty). The
results are illustrated by presenting likely trajectories for fourteen
dome-building eruptions on-going in 2015. Full representation of the
uncertainty is presented for two key eruptions, Soufri{\'{e}}re Hills Volcano
in Montserrat (10--139 years, median 35yr) and Sinabung, Indonesia (1--17
years, median 4yr). Uncertainties are high, but, importantly, quantifiable.
This work provides for the first time a quantitative and transferable method
and rationale on which to base long-term planning decisions for lava dome
forming volcanoes, with wide potential use and transferability to forecasts of
other types of eruptions and other adverse events across the geohazard
spectrum.
\\ ( http://arxiv.org/abs/1512.08495 ,  79kb)
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\\
arXiv:1512.08498 (*cross-listing*)
Date: Wed, 16 Dec 2015 13:40:16 GMT   (540kb,D)

Title: Quantum Mechanical Modeling of Nanoscale Light Emitting Diodes
Authors: Rulin Wang and Yu Zhang and Fuzhen Bi and GuanHua Chen and ChiYung Yam
Categories: cond-mat.mtrl-sci cond-mat.mes-hall physics.comp-ph
Comments: 5 pages, 3 figures
\\
  Understanding of the electroluminescence (EL) mechanism in optoelectronic
devices is important for further optimization of their efficiency and
effectiveness. Here, a quantum mechanical approach is formulated for modeling
EL processes in nanoscale light emitting diodes (LED). Based on nonequilibrium
Green's function quantum transport equations, interactions with electromagnetic
vacuum environment is included to describe electrically driven light emission
in the devices. Numerical studies of a silicon nanowire LED device are
presented. EL spectra of the nanowire device under different bias voltages are
simulated and, more importantly, propagation and polarization of emitted photon
can be determined using the current approach.
\\ ( http://arxiv.org/abs/1512.08498 ,  540kb)
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\\
arXiv:1512.08506 (*cross-listing*)
Date: Mon, 21 Dec 2015 11:17:38 GMT   (765kb)

Title: Modulation of diffusion rate of therapeutic peptide drugs using graphene
  oxide membranes
Authors: T. M. Puvirajesinghe, Z.L. Zhi, R. V. Craster, and S. Guenneau
Categories: cond-mat.mtrl-sci physics.bio-ph
\\
  We investigate diffusion of a peptide drug through Graphene Oxide (GO)
membranes that are modeled as a porous layered laminate constructed from
aligned flakes of GO. Our experiments using a peptide drug show a tunable
non-linear dependence of the peptide concentration upon time. This is confirmed
using numerical simulations with a diffusion equation accounting for the
photothermal degradation of fluorophores and an effective percolation model.
This modeling yields an interpretation of the control and delay of drug
diffusion through GO membranes. The ability to modulate the density of
hydrogel-like GO membranes to control drug release rates could be a step
forwards in tailoring drug release properties of the hydrogels for therapeutic
applications.
\\ ( http://arxiv.org/abs/1512.08506 ,  765kb)
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arXiv:1212.3863
replaced with revised version Mon, 28 Dec 2015 07:33:20 GMT   (1632kb)

Title: Geostationary Earth Orbit Satellite Model using Easy Java Simulation
Authors: Loo Kang Wee, Giam Hwee Goh
Categories: physics.ed-ph physics.comp-ph
Comments: 6 pages, 11 figures, 2013 Physics Education Volume 48 Number 1
Journal-ref: Phys. Educ. 48 72 (2013)
DOI: 10.1088/0031-9120/48/1/72
\\ ( http://arxiv.org/abs/1212.3863 ,  1632kb)
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\\
arXiv:1310.4517
replaced with revised version Sun, 27 Dec 2015 01:23:20 GMT   (1875kb,D)

Title: Using the Discrete Dipole Approximation and Holographic Microscopy to
  Measure Rotational Dynamics of Non-spherical Colloidal Particles
Authors: Anna Wang, Thomas G. Dimiduk, Jerome Fung, Sepideh Razavi, Ilona
  Kretzschmar, Kundan Chaudhary, Vinothan N. Manoharan
Categories: physics.optics cond-mat.soft
Comments: 11 pages, 9 figures, 2 tables
Journal-ref: Journal of Quantitative Spectroscopy and Radiative Transfer 146:
  499 (2014)
DOI: 10.1016/j.jqsrt.2013.12.019
\\ ( http://arxiv.org/abs/1310.4517 ,  1875kb)
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\\
arXiv:1409.8029
replaced with revised version Mon, 28 Dec 2015 07:11:42 GMT   (116kb)

Title: Universality of citation distributions for academic institutions and
  journals
Authors: Arnab Chatterjee, Asim Ghosh, Bikas K Chakrabarti
Categories: physics.soc-ph cs.DL
Comments: 9 pages, 6 figs + Supplementary information (8 pages, 7 fig, 6
  tables). Accepted in PLoS ONE
\\ ( http://arxiv.org/abs/1409.8029 ,  116kb)
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\\
arXiv:1410.6667
replaced with revised version Fri, 25 Dec 2015 16:27:26 GMT   (959kb)

Title: Self-starting stable coherent mode-locking in a two-section laser
Authors: R.M. Arkhipov, M.V. Arkhipov, I. Babushkin
Categories: physics.optics
Journal-ref: Optics Communications, V. 361, pp. 73-78 (2016)
DOI: 10.1016/j.optcom.2015.10.030
\\ ( http://arxiv.org/abs/1410.6667 ,  959kb)
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\\
arXiv:1411.4456
replaced with revised version Sat, 26 Dec 2015 03:16:37 GMT   (58kb)

Title: Compatibility of Larmor's formula with radiation reaction for a
  radiating charge
Authors: Ashok K. Singal
Categories: physics.class-ph
Comments: 22 pages, I figure, Foundations of Physics 2015. arXiv admin note:
  text overlap with arXiv:1410.7699
DOI: 10.1007/s10701-015-9978-2
\\ ( http://arxiv.org/abs/1411.4456 ,  58kb)
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\\
arXiv:1501.01535
replaced with revised version Mon, 28 Dec 2015 07:32:11 GMT   (1611kb)

Title: Understanding resonance graphs using Easy Java Simulations (EJS) and why
  we use EJS
Authors: Loo Kang Wee, Tat Leong Lee, Charles Chew, Darren Wong and Samuel Tan
Categories: physics.ed-ph
Comments: 6 pages, 8 figures, Physics Education Journal
Journal-ref: Phys. Educ. 50 (2015) 189-196
DOI: 10.1088/0031-9120/50/2/189
\\ ( http://arxiv.org/abs/1501.01535 ,  1611kb)
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\\
arXiv:1506.04329
replaced with revised version Mon, 28 Dec 2015 16:57:20 GMT   (741kb)

Title: Giant absorption of light by molecular vibrations on a chip
Authors: A. Karabchvesky and A. V. Kavokin
Categories: physics.optics cond-mat.mtrl-sci
\\ ( http://arxiv.org/abs/1506.04329 ,  741kb)
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\\
arXiv:1506.06917
replaced with revised version Mon, 28 Dec 2015 11:11:09 GMT   (1536kb,D)

Title: Bill2d - a software package for classical two-dimensional Hamiltonian
  systems
Authors: Janne Solanp\"a\"a, Perttu Luukko, Esa R\"as\"anen
Categories: physics.comp-ph
Journal-ref: Comp. Phys Comm. 199, 133-138 (2016)
DOI: 10.1016/j.cpc.2015.10.006
\\ ( http://arxiv.org/abs/1506.06917 ,  1536kb)
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\\
arXiv:1506.07194
replaced with revised version Sun, 27 Dec 2015 10:42:49 GMT   (4975kb)

Title: Advanced statistical methods for eye movement analysis and modeling: a
  gentle introduction
Authors: Giuseppe Boccignone
Categories: physics.data-an cs.CV q-bio.NC
Comments: Extended draft of Chapter to appear in "An introduction to the
  scientific foundations of eye movement research and its applications"
ACM-class: G.3; I.5; I.4
\\ ( http://arxiv.org/abs/1506.07194 ,  4975kb)
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\\
arXiv:1509.00790 (*cross-listing*)
replaced with revised version Mon, 28 Dec 2015 15:24:31 GMT   (684kb,D)

Title: Chiral plasmon in gapped Dirac systems
Authors: Anshuman Kumar and Andrei Nemilentsau and Kin Hung Fung and George
  Hanson and Nicholas X. Fang and Tony Low
Categories: cond-mat.mes-hall physics.optics
\\ ( http://arxiv.org/abs/1509.00790 ,  684kb)
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\\
arXiv:1509.02607
replaced with revised version Sat, 26 Dec 2015 13:43:19 GMT   (807kb)

Title: Phase matched second harmonic generation in an on-chip lithium niobate
  microresonator fabricated by femtosecond laser
Authors: Jintian Lin, Yingxin Xu, Jielei Ni, Min Wang, Zhiwei Fang, Lingling
  Qiao, Wei Fang, and Ya Cheng
Categories: physics.optics
Comments: 29 pages, 4 figues, supplementary material added
\\ ( http://arxiv.org/abs/1509.02607 ,  807kb)
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\\
arXiv:1509.03152
replaced with revised version Sun, 27 Dec 2015 21:51:31 GMT   (1695kb)

Title: Linear Stability Analysis of Compressible Channel Flow with Porous Walls
Authors: Iman Rahbari, Carlo Scalo
Categories: physics.flu-dyn
Comments: 18 pages, 8 figures, Invited contribution to the Whither Turbulence
  and Big Data in the 21st Century Springer Volume
MSC-class: 65N22, 65N25, 65N35
\\ ( http://arxiv.org/abs/1509.03152 ,  1695kb)
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arXiv:1509.08163
replaced with revised version Sun, 27 Dec 2015 21:19:11 GMT   (420kb)

Title: Formation of current singularity in a topologically constrained plasma
Authors: Yao Zhou, Yi-Min Huang, Hong Qin, and A. Bhattacharjee
Categories: physics.plasm-ph astro-ph.SR
Comments: 5 pages, 2 figures
\\ ( http://arxiv.org/abs/1509.08163 ,  420kb)
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arXiv:1510.08937 (*cross-listing*)
replaced with revised version Mon, 28 Dec 2015 05:38:52 GMT   (252kb)

Title: Measurement of $\theta_{13}$ in Double Chooz using neutron captures on
  hydrogen with novel background rejection techniques
Authors: Y. Abe, S. Appel, T. Abrah\~ao, H. Almazan, C. Alt, J.C. dos Anjos,
  J.C. Barriere, E. Baussan, I. Bekman, M. Bergevin, T.J.C. Bezerra, L.
  Bezrukov, E. Blucher, T. Brugi\`ere, C. Buck, J. Busenitz, A. Cabrera, L.
  Camilleri, R. Carr, M. Cerrada, E. Chauveau, P. Chimenti, A.P. Collin, J.M.
  Conrad, J.I. Crespo-Anad\'on, K. Crum, A.S. Cucoanes, E. Damon, J.V. Dawson,
  J. Dhooghe, D. Dietrich, Z. Djurcic, M. Dracos, A. Etenko, M. Fallot, F. von
  Feilitzsch, J. Felde, S.M. Fernandes, V. Fischer, D. Franco, M. Franke, H.
  Furuta, I. Gil-Botella, L. Giot, M. G\"oger-Neff, H. Gomez, L.F.G. Gonzalez,
  L. Goodenough, M.C. Goodman, N. Haag, T. Hara, J. Haser, D. Hellwig, M.
  Hofmann, G.A. Horton-Smith, A. Hourlier, M. Ishitsuka, J. Jochum, C. Jollet,
  F. Kaether, L.N. Kalousis, Y. Kamyshkov, M. Kaneda, D.M. Kaplan, et al. (81
  additional authors not shown)
Categories: hep-ex physics.ins-det
\\ ( http://arxiv.org/abs/1510.08937 ,  252kb)
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arXiv:1511.06927
replaced with revised version Mon, 28 Dec 2015 14:51:19 GMT   (605kb)

Title: Noctilucent Clouds Polarimetry: Twilight Measurements in a Wide Range of
  Scattering Angles
Authors: Oleg S. Ugolnikov, Igor A. Maslov, Boris V. Kozelov, Janna M. Dlugach
Categories: physics.ao-ph physics.space-ph
Comments: 17 pages, 8 figures
\\ ( http://arxiv.org/abs/1511.06927 ,  605kb)
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arXiv:1512.01776 (*cross-listing*)
replaced with revised version Mon, 28 Dec 2015 16:56:00 GMT   (458kb)

Title: First optimization principle for the ground state of translational
  invariant strongly-correlated quantum lattice models
Authors: Shi-Ju Ran
Categories: cond-mat.str-el math-ph math.MP physics.comp-ph
Comments: 9 pages, 9 figures
\\ ( http://arxiv.org/abs/1512.01776 ,  458kb)
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arXiv:1512.02366 (*cross-listing*)
replaced with revised version Mon, 28 Dec 2015 05:50:49 GMT   (1065kb)

Title: A compact 3.5-dB squeezed light source with atomic ensembles
Authors: Guzhi Bao, Xiaotian Feng, Bing Chen, Jinxian Guo, Heng Shen, Liqing
  Chen, Weiping Zhang
Categories: quant-ph physics.optics
\\ ( http://arxiv.org/abs/1512.02366 ,  1065kb)
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arXiv:1512.03366 (*cross-listing*)
replaced with revised version Mon, 28 Dec 2015 14:22:24 GMT   (38kb)

Title: The antineutrino energy structure in reactor experiments
Authors: P. Novella
Categories: hep-ex nucl-ex physics.ins-det
\\ ( http://arxiv.org/abs/1512.03366 ,  38kb)
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arXiv:1512.03505
replaced with revised version Fri, 25 Dec 2015 07:53:29 GMT   (212kb)

Title: Configuration interaction combined with spin-projection for strongly
  correlated molecular electronic structures
Authors: Takashi Tsuchimochi and Seiichiro Ten-no
Categories: physics.chem-ph
Comments: 5 pages, 3 figures, 1 table, to appear in J. Chem. Phys
\\ ( http://arxiv.org/abs/1512.03505 ,  212kb)
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arXiv:1512.04338 (*cross-listing*)
replaced with revised version Sun, 27 Dec 2015 21:41:11 GMT   (285kb)

Title: An Entropic Formulation of Tunneling Time
Authors: Durmus A. Demir, Tugrul Guner
Categories: quant-ph cond-mat.mes-hall physics.atom-ph
Comments: 8 pp, 2 embedded figs. Problem with viewing the figures is fixed
Report-no: IZTECH-P06/2015
\\ ( http://arxiv.org/abs/1512.04338 ,  285kb)
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arXiv:1512.04556 (*cross-listing*)
replaced with revised version Mon, 28 Dec 2015 15:32:57 GMT   (133kb)

Title: Spectral Functions of the Uniform Electron Gas via Coupled-Cluster
  Theory and Comparison to the $GW$ and Related Approximations
Authors: James McClain, Johannes Lischner, Thomas Watson, Devin A. Matthews,
  Enrico Ronca, Steven G. Louie, Timothy C. Berkelbach, and Garnet Kin-Lic Chan
Categories: cond-mat.mtrl-sci cond-mat.str-el physics.chem-ph
Comments: 6 pages, 2 figures
\\ ( http://arxiv.org/abs/1512.04556 ,  133kb)
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arXiv:1512.04721 (*cross-listing*)
replaced with revised version Mon, 28 Dec 2015 20:38:55 GMT   (9kb)

Title: Spectrum of secondary electrons emitted during the nuclear
  $\beta^{-}$-decay of the tritium atom
Authors: Alexei M. Frolov
Categories: nucl-th physics.atom-ph
Comments: arXiv admin note: text overlap with arXiv:1511.06475
\\ ( http://arxiv.org/abs/1512.04721 ,  9kb)
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arXiv:1512.06169
replaced with revised version Sun, 27 Dec 2015 09:25:46 GMT   (1097kb,D)

Title: Technological novelty profile and invention's future impact
Authors: Daniel Kim, Daniel Burkhardt Cerigo, Hawoong Jeong and Hyejin Youn
Categories: physics.soc-ph physics.data-an
Comments: 20 pages, 7 figures
\\ ( http://arxiv.org/abs/1512.06169 ,  1097kb)
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arXiv:1512.07753
replaced with revised version Fri, 25 Dec 2015 08:07:20 GMT   (502kb,D)

Title: Spatiotemporal coherent control of light through a multiply scattering
  medium with the Multi-Spectral Transmission Matrix
Authors: Mickael Mounaix, Daria Andreoli, Hugo Defienne, Giorgio Volpe, Ori
  Katz, Samuel Gr\'esillon, and Sylvain Gigan
Categories: physics.optics
Comments: 5 pages, 4 figures
\\ ( http://arxiv.org/abs/1512.07753 ,  502kb)
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arXiv:1512.07827 (*cross-listing*)
replaced with revised version Mon, 28 Dec 2015 16:02:32 GMT   (799kb)

Title: Community Detection in Complex Networks Using Density-based Clustering
  Algorithm
Authors: Tao You, Ben-Chang Shia, Zhong-Yuan Zhang
Categories: cs.SI physics.soc-ph
\\ ( http://arxiv.org/abs/1512.07827 ,  799kb)
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arXiv:1512.07836
replaced with revised version Mon, 28 Dec 2015 05:39:44 GMT   (35kb,D)

Title: General formulation of process noise matrix for track fitting with
  Kalman filter
Authors: Kolahal Bhattacharya, Sudeshna Banerjee, Naba K Mondal
Categories: physics.ins-det hep-ex
Comments: Total 18 pages, 2 figures
\\ ( http://arxiv.org/abs/1512.07836 ,  35kb)
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