Measurement of Heavy Flavor Properties at CMS

  • Muhammad AlibordiEmail author
Conference paper
Part of the Springer Proceedings in Physics book series (SPPHY, volume 234)


Measurements of lifetimes in the decay channels \(B^0\rightarrow J/\psi K^*(892)^0\), \(B^0\rightarrow J/\psi K^0_s\), \(B^0_s\rightarrow J/\psi \pi ^+\pi ^-\), \(B^0_s\rightarrow J/\psi \phi \), \(\varLambda ^0_b\rightarrow J/\psi \varLambda ^0\) and \(B^+_c\rightarrow J/\psi \pi ^+\), and polarization of \(\varLambda _b\) in \(\varLambda _b\rightarrow J/\psi \varLambda \) decays are presented. The data used are collected by the CMS experiment in proton–proton collisions at centre-of-mass energy \(\sqrt{s}=\) 7 and 8 TeV corresponding to an integrated luminosity of 5 fb\(^{-1}\) and 19.7 fb\(^{-1}\), respectively. The measured lifetimes in \({\upmu }\)m are \(c\tau _{B^0\rightarrow J/\psi K^*(892)^0}= \, 453.0\pm 1.6(\mathrm {stat})\pm 1.8(\mathrm {syst})\), \(c\tau _{B^0\rightarrow J/\psi K^0_s}=457.8\pm 2.7(\mathrm {stat})\pm 2.8(\mathrm {syst})\), \(c\tau _{B^0_s\rightarrow J/\psi \phi }=443.9\pm 2.0(\mathrm {stat})\pm 1.5(\mathrm {syst})\), \(c\tau _{B^0_s\rightarrow J/\psi \pi ^+\pi ^-}=502.7\pm 10.2(\mathrm {stat})\pm 3.4(\mathrm {syst})\), \(c\tau _{\varLambda ^0_b\rightarrow J/\psi \varLambda ^0}=442.9\pm 8.2(\mathrm {stat})\pm 2.8(\mathrm {syst})\) and \(c\tau _{B^+_c\rightarrow J/\psi \pi ^+}=162.3\pm 7.8(\mathrm {stat})\pm 4.2(\mathrm {syst})\). The measured \(\varLambda _b^0\) polarization is \(P=0.00 \pm 0.06 (\mathrm {stat}) \pm 0.06(\mathrm {syst})\) along with the asymmetry parameter \( \alpha _1=0.14 \pm 0.14(\mathrm {stat}) \pm 0.10(\mathrm {syst})\).


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© Springer Nature Switzerland AG 2019

Authors and Affiliations

  1. 1.Indian Institute of Technology MadrasChennaiIndia

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