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arXiv · 2401.03720

CKM $γ$ measurements at LHCb

Lei Hao
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Abstract

The tree-level measurement of the CKM $γ$ angle is a crucial test of $CP$ violation in the Standard Model (SM). Discrepancies between direct measurements (tree-level decays) and indirect measurements (loop decays) could indicate physics beyond the SM. Recent measurements using decays such as $B^0 \rightarrow DK^{*0}, B^{\pm} \rightarrow [Dπ^0/γ]_{D^*}h^{\pm}$ (where $D$ decays to $K_{S}^{0} h^+h^-$ with $h=K, π$) and $B^{\pm} \rightarrow [h'^+h'^-π^+π^-]_Dh^{\pm}$ are presented. Additionally, the combination of previous $γ$ measurements at LHCb, excluding the aforementioned results, is also presented. The LHCb result, with a precision of $(63.8^{+3.5}_{-3.7})^{\circ}$ establishes itself as a dominant measurement in this field.

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Lei Hao. 2024-01-08. CKM $γ$ measurements at LHCb. https://arxiv.org/abs/2401.03720

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