Global analysis of charm mixing parameters and determination of the CKM angle $\gamma$

TL;DR

This paper provides a comprehensive global analysis of charm mixing parameters and the CKM angle gamma, using updated data and a framework of approximate universality to extract fundamental CP violation parameters.

Contribution

It introduces a novel global analysis framework that combines charm mixing and beauty decay data to determine CP violation parameters and the CKM angle gamma.

Findings

Charm mixing parameters: x = (0.401 ± 0.043)% and y = (0.610 ± 0.017)%

CP-violating phases: φ₂^M = (0.13 ± 0.70)° and φ₂^Γ = (2.1 ± 1.6)°

CKM angle gamma: (65.7 ± 2.5)°

Abstract

We present an updated global analysis of beauty decays sensitive to the angle $\gamma$ of the Cabibbo-Kobayashi-Maskawa matrix and of $D$-meson mixing data in the framework of approximate universality, in which CP violation in $D-\overline{D}$ mixing is described in terms of two universal weak phases corresponding to dispersive and absorptive contributions. We extract the fundamental theoretical parameters determining absorptive and dispersive contributions to $D$ meson mixing and CP violation, together with the angle $\gamma$. The results for the charm mixing parameters are $x_{12} \simeq x = (0.401 \pm 0.043)\%$ and $y_{12} \simeq y = (0.610 \pm 0.017)\%$, while the two CP-violating phases are given by $\phi_2^M = (0.13 \pm 0.70)^{\circ}$ and ${\phi}_2^{\Gamma} = (2.1 \pm 1.6)^{\circ}$. The angle $\gamma$ is found to be $\gamma = (65.7 \pm 2.5)^{\circ}$, in excellent agreement with the indirect determination from the Unitarity Triangle analysis.