D0 Evidence for CP Violation and Implication for CPT Violation in B-Meson Mixing

TL;DR

This paper reports the first evidence of anomalous CP violation in B-meson mixing, with implications for CPT violation, based on charge asymmetry measurements at the Fermilab Tevatron Collider.

Contribution

It provides the first experimental evidence of CP violation in B-meson mixing that is inconsistent with the Standard Model, and explores potential CPT violation effects.

Findings

3.2 standard deviations from Standard Model prediction

First evidence of CPT-invariant anomalous CP violation in B mesons

Sensitivity to CPT violation in B0_s system

Abstract

An analysis from the D0 Collaboration measuring the charge asymmetry A^b_sl of like-sign dimuon events due to semileptonic b-hadron decays at the Fermilab Tevatron Collider is described. It differs by 3.2 standard deviations from the Standard Model prediction to provide first evidence of CPT-invariant anomalous CP violation in the mixing of neutral B mesons, and is compared to the CP-violating phase obtained from a D0 analysis of the time-dependent decay angles in B0_s -> J/psi phi. If CPT violation is allowed, the dimuon asymmetry also yields the first sensitivity to CPT violation in the B0_s system.