Measuring CP Violating Phase in Beauty Baryon Decays.

Rahul Sinha,N G Deshpande,Shibasis Roy

doi:10.1103/physrevlett.128.081803

Abstract

One of the outstanding problems in physics is to explain the baryon-antibaryon 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-antibaryon asymmetry. The 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 the CP violating phase in b baryons, using interference arising implicitly due to Bose symmetry considerations of the decaying amplitudes.

Highlights

The proposal to observe CP violation in Σ-baryon decays [1] was first made by Okubo in 1957, much before the first observation of CP violation in 1964 by Fitch and Cronin using neutral K mesons
CP violating phases have been measured accurately in Bmeson decays and the measurements are found consistent within the standard model (SM) and in agreement with the Kobayashi-Maskawa hypothesis
This is essential since measurements in meson decays indicate that CP violation in the SM is by itself insufficient to explain the observed baryon– antibaryon asymmetry [4]

Summary

Introduction

The proposal to observe CP violation in Σ-baryon decays [1] was first made by Okubo in 1957, much before the first observation of CP violation in 1964 by Fitch and Cronin using neutral K mesons. It is well known that for CP violation to be observed the amplitude must have two contributions with both having different strong phases and weak phases.

Objectives

Results

Conclusion