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arXiv · 2109.10751

Measuring $\mathbf{CP}$ violating phase in beauty baryon decays

Rahul Sinha·Shibasis Roy·N. G. Deshpande
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Abstract

One of the outstanding problems in physics is to explain the baryon-anti-baryon asymmetry observed in nature. According to the well-known Sakharov criterion for explaining the observed asymmetry, it is essential that $CP$ violation exist. Even though $CP$ violation has been observed in meson decays and is an integral part of the standard model (SM), measurements in meson decays indicate that $CP$ violation in the SM is insufficient to explain the observed baryon-anti-baryon asymmetry. SM predicts the existence of yet to be observed $CP$ violation in baryon decays. A critical test of the SM requires that $CP$ violation be measured in baryon decays as well, in order to verify that it agrees with the measurement using meson decays. In this letter we propose a new method to measure $CP$ violating phase in $b$-baryons, using interference arising implicitly due to Bose symmetry considerations of the decaying amplitudes.

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Rahul Sinha, Shibasis Roy, N. G. Deshpande. 2021-09-22. Measuring $\mathbf{CP}$ violating phase in beauty baryon decays. https://doi.org/10.1103/physrevlett.128.081803

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