Measurement of the Λb lifetime and mass

Jones, Roger and Chilingarov, Alexandre and Kartvelishvili, Vakhtang and Love, Peter and Borissov, Guennadi and Fox, Harald and Smizanska, Maria and Bouhova-Thacker, Evelina and Davidson, Ruth and de Mora, Lee and Dearnaley, William and Walder, James and Hughes, Gareth and Long, Robin and Barton, Adam and Maddocks, Harvey and Henderson, Robert and Allison, Lee and Grimm, Kathryn and Price, Darren (2013) Measurement of the Λb lifetime and mass. Physical Review D – Particles and Fields, 87 (3). ISSN 1550-2368

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A measurement of the Λb0 lifetime and mass in the decay channel Λb0→J/ψ(μ+μ-)Λ0(pπ-) is presented. The analysis uses a signal sample of about 2200 Λb0 and Λ̅ b0 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 Λb0 lifetime and mass. They are measured to be τΛb=1.449±0.036(stat)±0.017(syst)  ps and mΛb=5619.7±0.7(stat)±1.1(syst)  MeV.

Item Type:
Journal Article
Journal or Publication Title:
Physical Review D – Particles and Fields
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© 2013 CERN, for the ATLAS Collaboration
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Deposited On:
04 Jun 2013 08:54
Last Modified:
03 Jul 2020 01:01