Measurement of beta_s at CDF

TL;DR

This paper reports the most recent measurements of the CP violating phase beta_s, B0s lifetime, and width difference using CDF data, incorporating new decay channels and improved analysis techniques for enhanced precision.

Contribution

First measurement of beta_s including S-wave contributions from B0s decays, with significant data and analysis improvements for higher precision.

Findings

Measurement of beta_s with new decay channels

Most precise B0s lifetime and width difference measurements

Enhanced analysis methods and larger signal sample

Abstract

The latest results for the measurement of the CP violating phase beta_s in B0s -> J/psi phi decays, from 5.2 fb-1 integrated luminosity of CDF data are presented. For the first time, this measurement includes the contribution of B0s -> J/psi K+K- or B0s -> J/psi f0 events to the signal sample, where the f0 and non-resonant K+K- are S-wave states. Additional improvements to the analysis include more than doubling the signal sample, improved selection and particle ID, and fully calibrated flavour tagging for the full dataset. Additionally, the world's most precise single measurements of the B0s lifetime, tau_s, and width difference, DeltaGamma_s are given.