Date: Thu, 25 Dec 08 01:00:24 GMT Subject: hep-ex daily 4 new + 2 crosses received by eprepget ------------------------------------------------------------------------------ ------------------------------------------------------------------------------ Send any complaints regarding submissions directly to submitter. ------------------------------------------------------------------------------ Point your www client at http://arXiv.org/ To unsubscribe, e-mail To: hep-ex@arXiv.org, Subject: cancel ------------------------------------------------------------------------------ received by eprepget from Tue 23 Dec 08 21:00:01 GMT to Wed 24 Dec 08 21:00:01 GMT ------------------------------------------------------------------------------ \\ arXiv:0812.4458 Date: Tue, 23 Dec 2008 22:29:57 GMT (60kb) Title: Measurement of Cross Sections for $b$ Jet Production in Events with a $Z$ Boson in $p\bar{p}$ Collisions at $\sqrt{s}=1.96$ TeV Authors: CDF collaboration: T. Aaltonen, et al Categories: hep-ex Comments: submitted to Phys. Rev. D Report-no: FERMILAB-PUB-08-576-E \\ A measurement of the $\bjet$ production cross section is presented for events containing a $Z$ boson produced in $p\bar{p}$ collisions at $\sqrt{s}=1.96$ TeV, using data corresponding to an integrated luminosity of 2 fb$^{-1}$ collected by the CDF II detector at the Tevatron. $Z$ bosons are selected in the electron and muon decay modes. Jets are considered with transverse energy $E_T>20$ GeV and pseudorapidity $|\eta|<1.5$ and are identified as $\bjets$ using a secondary vertex algorithm. The ratio of the integrated $Z+\bjet$ cross section to the inclusive $Z$ production cross section is measured to be $3.32 \pm 0.53 {\rm (stat.)} \pm 0.42 {\rm (syst.)}\times 10^{-3}$. This ratio is also measured differentially in jet $E_T$, jet $\eta$, $Z$-boson transverse momentum, number of jets, and number of $\bjets$. The predictions from leading order Monte Carlo generators and next-to-leading-order QCD calculations are found to be consistent with the measurements within experimental and theoretical uncertainties. \\ ( http://arxiv.org/abs/0812.4458 , 60kb) ------------------------------------------------------------------------------ \\ arXiv:0812.4469 Date: Wed, 24 Dec 2008 01:21:08 GMT (236kb) Title: Top Quark Mass Measurement in the Lepton plus Jets Channel Using a Modified Matrix Element Method Authors: CDF Collaboration, T. Aaltonen, et al Categories: hep-ex Comments: 46 pages, 16 figures. Submitted to Phys. Rev. D Report-no: FERMILAB-PUB-08-574-E \\ We report a measurement of the top quark mass, m_t, obtained from ppbar collisions at sqrt(s) = 1.96 TeV at the Fermilab Tevatron using the CDF II detector. We analyze a sample corresponding to an integrated luminosity of 1.9 fb^-1. We select events with an electron or muon, large missing transverse energy, and exactly four high-energy jets in the central region of the detector, at least one of which is tagged as coming from a b quark. We calculate a signal likelihood using a matrix element integration method, with effective propagators to take into account assumptions on event kinematics. Our event likelihood is a function of m_t and a parameter JES that determines /in situ/ the calibration of the jet energies. We use a neural network discriminant to distinguish signal from background events. We also apply a cut on the peak value of each event likelihood curve to reduce the contribution of background and badly reconstructed events. Using the 318 events that pass all selection criteria, we find m_t = 172.7 +/- 1.8 (stat. + JES) +/- 1.2 (syst.) GeV/c^2. \\ ( http://arxiv.org/abs/0812.4469 , 236kb) ------------------------------------------------------------------------------ \\ arXiv:0812.4527 Date: Wed, 24 Dec 2008 12:29:50 GMT (176kb) Title: A High Resolution Neutrino Experiment in a Magnetic Field for Project-X at Fermilab Authors: S. R. Mishra, R. Petti, C. Rosenfeld Categories: hep-ex Comments: 6 pages, 2 figures \\ We propose a new high-resolution neutrino experiment within a dipole magnetic field, HiResM$\nu$. This experiment will run along with long-baseline neutrino oscillation experiments (LBL$\nu$) such as NO$\nu$A, a large-cavity detector at DUSEL, or a Liquid-Argon detector in the Medium-Energy (ME) configuration of the NuMI-beam. Assuming the 120 GeV Main Injector proton intensities we anticipate 140(50) million $\nu_\mu$ ($\overline{\nu}_\mu$) Charged-Current (CC) events in the fiducial volume, for 3(4)-year run with the ME (anti)neutrino beam. Alternatively, the same statistics could be collected in just 1(1.5) year with the High Energy (HE) beam configuration. The goals of HiResM$\nu$ are twofold. It will measure the relative abundance and the energy spectrum of $\nu_\mu$, $\overline{\nu}_\mu$, $\nu_e$ and $\overline{\nu}_e$ CC-interactions, which are directly relevant to LBL$\nu$. It will serve as an `Event-Generator' of real neutrino interactions to estimate backgrounds and efficiencies in LBL$\nu$. As such, it will provide a quantitative determination of the overall energy-scale of neutrino CC interactions and of hadronic multiplicities for all CC and Neutral-Current (NC) event topologies. In addition, it will perform precise measurements of electroweak parameters, of (semi)exclusive processes such as quasi-elastic, resonance, $\pi^0$ / $K^0_S$ / $\Lambda$/charm-hadron production, as well as of the hadronic structure of nucleons and nuclei. We expect to reach a sensitivity of about 0.2% on the weak mixing angle by combining different channels. The new experiment will also perform searches for new physics beyond the Standard Model. \\ ( http://arxiv.org/abs/0812.4527 , 176kb) ------------------------------------------------------------------------------ \\ arXiv:0812.4543 Date: Wed, 24 Dec 2008 15:58:50 GMT (222kb) Title: A study of quasi-elastic muon neutrino and antineutrino scattering in the NOMAD experiment Authors: NOMAD Collaboration Categories: hep-ex Comments: 26 pages, 18 figures, to be submitted to Eur.Phys.J.C \\ We have studied the muon neutrino and antineutrino quasi-elastic (QEL) scattering reactions using a set of experimental data collected by the NOMAD collaboration. We have performed measurements of the cross-section of these processes on a nuclear target (mainly Carbon) normalizing it to the total (anti)neutrino charged current cross-section. The axial mass parameter was extracted from the measured quasi-elastic neutrino cross-section. It is consistent with the axial mass values recalculated from the antineutrino cross-section and extracted from the pure Q^2 shape analysis of the high purity sample of neutrino quasi-elastic 2-track events, but has smaller systematic error. Our measured M_A mass is found to be in good agreement with the world average value obtained in previous deuterium filled bubble chamber experiments. The NOMAD measurement of M_A is lower than those recently published by K2K and MiniBooNE collaborations. However, within the large errors quoted by these experiments on M_A, these results are compatible with the more precise NOMAD value. \\ ( http://arxiv.org/abs/0812.4543 , 222kb) %-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%- ------------------------------------------------------------------------------ \\ arXiv:0812.4092 (*cross-listing*) Date: Mon, 22 Dec 2008 04:51:12 GMT (39kb) Title: Further insights into the "$\rho\pi$ puzzle" Authors: Qiang Zhao, Gang Li, and Chao-Hsi Chang Categories: hep-ph hep-ex Comments: 7 pages, 2 figures, proceeding of "The Conference on Interdisciplinary Fields of Particle Physics, Nuclear Physics and Cosmology", Aug. 2-4, 2008, Yunnan, China \\ Based on a systematic investigation of $J/\psi(\psi^\prime)\to VP$, where $V$ and $P$ stand for light vector and pseudoscalar mesons, we identify the role played by the electromagnetic (EM) transitions and intermediate meson loop transitions, which are essential ingredients for understanding the $J/\psi$ and $\psi^\prime$ couplings to $VP$. We show that on the one hand, the EM transitions have relatively larger interferences in $\psi^\prime\to \rho\pi$ and $K^*\bar{K}+c.c.$ as explicitly shown by vector meson dominance (VMD). On the other hand, the strong decay of $\psi^\prime$ receives relatively larger destructive interferences from the intermediate meson loop transitions. By identifying these mechanisms in an overall study of $J/\psi(\psi^\prime)\to VP$, we provide a coherent understanding of the so-called "$\rho\pi$ puzzle". \\ ( http://arxiv.org/abs/0812.4092 , 39kb) ------------------------------------------------------------------------------ \\ arXiv:0812.4260 (*cross-listing*) Date: Mon, 22 Dec 2008 18:04:24 GMT (199kb) Title: Can universality of the QCD evolution be checked in W boson decays into hadrons? Authors: A.V. Kisselev and V.A. Petrov Categories: hep-ph hep-ex Comments: 14 pages, 7 figures \\ Hadron multiplicity from $W$ boson is calculated in pQCD. The agreement of our theoretical predictions with the LEP data says in favor of universality of the QCD evolution in hard processes. \\ ( http://arxiv.org/abs/0812.4260 , 199kb) %%--%%--%%--%%--%%--%%--%%--%%--%%--%%--%%--%%--%%--%%--%%--%%--%%--%%--%%--%% %%%---%%%---%%%---%%%---%%%---%%%---%%%---%%%---%%%---%%%---%%%---%%%---%%%--- For subscribe options to combined physics archives, e-mail To: physics@arXiv.org, Subject: subscribe ----------------------------------------------------------------------------- For help on viewing and making submissions, see http://arXiv.org/help/ For a list of archive mirror sites, see http://arXiv.org/servers.html ----------------------------------------------------------------------------- Third-party submissions cause excessive problems. Author self-submissions are exceedingly preferred. E-mail submissions have been discontinued in favor of better support for Web submissions. See http://arXiv.org/help/uploads