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arXiv · 0904.3907

Search for CP violation in semileptonic Bs decays

D0 Collaboration·V. Abazov
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Abstract

We have performed a search for CP violation in a sample of Bs -> Ds mu X decays corresponding to $5$~fb$^{-1}$ of proton-antiproton collisions collected by the D0 detector in Run~II at the Fermilab Tevatron Collider. New physics in $B_s^0$ mixing could contribute a significant CP violating weak phase, which would be observed as a difference in the decay-time distribution for $B_s^0\to \bar{B}_s^0$ oscillated states versus that for $\bar{B}_s^0\to {B}_s^0$. A fit to the decay-time distributions of the $B_s^0/\bar{B}_s^0$ candidates yields the flavor-specific asymmetry $a_{fs}^{s}=[-1.7\pm 9.1\mathrm{(stat)}^{+1.4}_{-1.5}\mathrm{(syst)}] \times 10^{-3}$, which excludes CP violation due to new physics within the experimental sensitivity.

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D0 Collaboration, V. Abazov. 2010-10-08. Search for CP violation in semileptonic Bs decays. https://doi.org/10.1103/physrevd.82.012003%2010.1103%2Fphysrevd.83.119901

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