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arXiv · 1112.0868

CP violation in $B^0_s$ mixing with LHCb

Georg Krocker
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Abstract

The determination of the CP-violating phase $ϕ_s$ in $B^0_s \rightarrow J/ψϕ$ decays is one of the key goals of the LHCb experiment. Its value is predicted to be very small in the Standard Model but can be significantly enhanced in many models of new physics. An angular analysis of the decay $\PBs\to\PJpsi\Pphi$ using about 340\invpicobarn of data is presented resulting in a Standard Model compatible value of $ϕ_s^{\PJpsi\Pphi}=0.13\pm0.18(\mathrm{stat.})\pm0.07(\mathrm{syst.})\,\mathrm{rad}$. An additional extraction of $ϕ_s$ from the decay $\PBs\to\PJpsi f_0(980)$ is performed for the first time in LHCb. A combination results in $ϕ_s=0.05\pm0.17(\mathrm{stat.})\pm0.07(\mathrm{syst.})\,\mathrm{rad}$. To resolve the fast mixing frequency is an essential prerequisite of this analysis. This is demonstrated by a precision measurement of $Δm_s=17.725\pm0.041(\mathrm{stat.})\pm0.026(\mathrm{syst.})\ps^{-1}$.

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Georg Krocker. 2011-12-05. CP violation in $B^0_s$ mixing with LHCb. https://arxiv.org/abs/1112.0868

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