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arXiv · 0710.3235

Studies of CP-conserving and CP-violating Bs mixing parameters with the D0 experiment

James Walder
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Abstract

This paper summarises the recent results of the Run IIa D0 experiment at the Tevatron Collider at Fermilab on the observable parameters of the $B_{s}$ meson. A measurement of the branching fraction $B_s->D_s^{(*)}D_s^{(*)}$ is reported, which provides an estimate of the width difference $ΔΓ_{s}^{CP}/ΔΓ_{s}$. Through the decay $B_{s} \to J/ψϕ$ the width difference $ΔΓ_{s}$ is extracted, and for the first time a constraint is set on the CP-violating phase $ϕ_{s}$, although a four-fold ambiguity remains. This result is combined with other D0 measurements to yield $ΔΓ_{s}=0.13\pm0.09 {\rm ps^{-1}}$, $ϕ_{s} = -0.70^{+0.47}_{-0.39}$.

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James Walder. 2007-10-17. Studies of CP-conserving and CP-violating Bs mixing parameters with the D0 experiment. https://arxiv.org/abs/0710.3235

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