English

Measurement of the Lambda_b lifetime and mass in the ATLAS experiment

High Energy Physics - Experiment 2013-06-11 v3

Abstract

A measurement of the Lambda_b lifetime and mass in the decay channel Lambda_b -> J/psi(mu^+ mu^-) Lambda^0(p pi^-) is presented. The analysis uses a signal sample of about 2200 Lambda_b and anti-Lambda_b decays that are reconstructed in 4.9 fb^-1 of ATLAS pp collision data collected in 2011 at the LHC center-of-mass energy of 7 TeV. A simultaneous mass and decay time maximum likelihood fit is used to extract the Lambda_b lifetime and mass. They are measured to be tau(Lambda_b) = 1.449 +/- 0.036(stat) +/- 0.017(syst) ps and m(Lambda_b) = 5619.7 +/- 0.7(stat) +/- 1.1(syst) MeV.

Keywords

Cite

@article{arxiv.1207.2284,
  title  = {Measurement of the Lambda_b lifetime and mass in the ATLAS experiment},
  author = {ATLAS Collaboration},
  journal= {arXiv preprint arXiv:1207.2284},
  year   = {2013}
}

Comments

7 pages plus author list (20 pages total), 3 figures, 2 tables, submitted to Physical Review D. All figures including auxiliary figures are available at http://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/BPHY-2012-03/