The Theoretical status of $\bar{B}-B$-mixing and lifetimes of heavy hadrons

TL;DR

This paper reviews the theoretical understanding of heavy hadron lifetimes and B-mixing parameters, emphasizing the potential of certain ratios to detect new physics despite uncertainties in decay constants.

Contribution

It provides an updated theoretical analysis of heavy hadron lifetime ratios and B-mixing quantities, highlighting the ratio with minimal uncertainties as a tool for new physics searches.

Findings

The ratio ΔΓ_s / ΔM_s can be determined with negligible non-perturbative uncertainties.

Large uncertainties exist in ΔM_s and ΔΓ_s due to decay constants.

Theoretical predictions can guide new physics searches in B-mixing data.

Abstract

In this talk we review the theoretical status of the lifetime ratios of heavy hadrons and of the B-mixing quantities $\Delta M_s$, $\Delta \Gamma_s$ and $\phi_s$. While $\Delta M_s$ and $\Delta \Gamma_s$ suffer from large uncertainties due to the badly known decay constants, the ratio $\Delta \Gamma_s / \Delta M_s$ can be determined with almost no non-perturbative uncertainties, therefore it can be used to look for possible new physics effects.