Measurement of the $WZ$ Cross Section and Triple Gauge Couplings in $p \bar p$ Collisions at $\sqrt{s} = 1.96$ TeV
ArXiv 1202.6629 (2012)
Abstract:
This Letter describes the current most precise measurement of the $WZ$ production cross section as well as limits on anomalous $WWZ$ couplings at a center-of-mass energy of 1.96 TeV in proton-antiproton collisions for the Collider Detector at Fermilab (CDF). $WZ$ candidates are reconstructed from decays containing three charged leptons and missing energy from a neutrino, where the charged leptons are either electrons or muons. Using data collected by the CDF II detector (7.1 fb$^{-1}$ of integrated luminosity), 63 candidate events are observed with the expected background contributing $8 \pm 1$ events. The measured total cross section $蟽(p \bar p \to WZ) = 3.93_{-0.53}^{+0.60}(\text{stat})_{-0.46}^{+0.59}(\text{syst}) $ pb is in good agreement with the standard model prediction of $3.50\pm 0.21$. The same sample is used to set limits on anomalous $WWZ$ couplings.A measurement of the ratio of the W and Z cross sections with exactly one associated jet in pp collisions at s=7TeV with ATLAS
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics 708:3-5 (2012) 221-240
Abstract:
The ratio of production cross sections of the W and Z bosons with exactly one associated jet is presented as a function of jet transverse momentum threshold. The measurement has been designed to maximise cancellation of experimental and theoretical uncertainties, and is reported both within a particle-level kinematic range corresponding to the detector acceptance and as a total cross-section ratio. Results are obtained with the ATLAS detector at the LHC in pp collisions at a centre-of-mass energy of 7 TeV using an integrated luminosity of 33 pb-1. The results are compared with perturbative leading-order, leading-log, and next-to-leading-order QCD predictions, and are found to agree within experimental and theoretical uncertainties. The ratio is measured for events with a single jet with pT>30 GeV to be 8.73卤0.30(stat)卤0.40(syst) in the electron channel, and 8.49卤0.23(stat)卤0.33(syst) in the muon channel. 漏 2012 CERN.Measurement of the production cross section for Z/纬* in association with jets in pp collisions at 鈭歴=7TeV with the ATLAS detector
Physical Review D - Particles, Fields, Gravitation and Cosmology 85:3 (2012)
Abstract:
Results are presented on the production of jets of particles in association with a Z/纬* boson, in proton-proton collisions at 鈭歴=7TeV with the ATLAS detector. The analysis includes the full 2010 data set, collected with a low rate of multiple proton-proton collisions in the accelerator, corresponding to an integrated luminosity of 36pb-1. Inclusive jet cross sections in Z/纬* events, with Z/纬* decaying into electron or muon pairs, are measured for jets with transverse momentum pT>30GeV and jet rapidity |y|<4.4. The measurements are compared to next-to-leading-order perturbative QCD calculations, and to predictions from different Monte Carlo generators implementing leading-order matrix elements supplemented by parton showers. 漏 2012 CERN.Planet Hunters: New Kepler planet candidates from analysis of quarter 2
ArXiv 1202.6007 (2012)
Abstract:
We present new planet candidates identified in NASA Kepler quarter two public release data by volunteers engaged in the Planet Hunters citizen science project. The two candidates presented here survive checks for false-positives, including examination of the pixel offset to constrain the possibility of a background eclipsing binary. The orbital periods of the planet candidates are 97.46 days (KIC 4552729) and 284.03 (KIC 10005758) days and the modeled planet radii are 5.3 and 3.8 R_Earth. The latter star has an additional known planet candidate with a radius of 5.05 R_Earth and a period of 134.49 which was detected by the Kepler pipeline. The discovery of these candidates illustrates the value of massively distributed volunteer review of the Kepler database to recover candidates which were otherwise uncatalogued.Measurements of the angular distributions in the decays B鈫扠( *)渭+渭- at CDF
Physical Review Letters 108:8 (2012)