Heavy Quark Masses from the $Q\bar Q$ Threshold and the Upsilon Expansion

TL;DR

This paper reviews the use of the 1S mass scheme, a new heavy quark mass definition, which improves the accuracy of mass determinations and the convergence of perturbative calculations in heavy quarkonium studies.

Contribution

It introduces and discusses the 1S mass scheme for heavy quarks, demonstrating its advantages in precision and convergence over previous methods.

Findings

The 1S scheme yields very accurate heavy quark mass determinations.

Perturbative expansions in the 1S scheme show improved convergence.

Updated results with higher order calculations reinforce the scheme's effectiveness.

Abstract

Recent results from studies using half the perturbative mass of heavy quark-antiquark n=1, ${}^3S_1$ quarkonium as a new heavy quark mass definition for problems where the characteristic scale is smaller than or of the same order as the heavy quark mass are reviewed. In this new scheme, called the 1S mass scheme, the heavy quark mass can be determined very accurately, and many observables like inclusive B decays show nicely converging perturbative expansions. Updates on results using the 1S scheme due to new higher order calculations are presented.