Charm Quark Mass from Inclusive Semileptonic B Decays

TL;DR

This paper determines the MSbar charm-quark mass ${\overline m_c(\overline m_c)}$ from a global fit to inclusive semileptonic B-decay data, achieving 1224 MeV with experimental and theoretical uncertainties. It addresses the renormalon problem in pole masses by implementing consistent cancellations in the bottom–charm system, using HQET-based perturbative relations up to three loops and including charm-mass effects in the bottom–1S mass relation. Two analysis frameworks (Methods A and B) with expansions up to $\varphi=3$ (including $2_c$ and $3_c$) are employed, and the final results emphasize the importance of consistent truncation and scale choices. The findings are compatible with sum-rule determinations and suggest that future ${\cal O}(\alpha_s^2)$ analyses and higher-order corrections can further reduce the theory uncertainties to the 50 MeV level or below.

Abstract

The MSbar charm quark mass is determined to be m_c(m_c)=1224+-17+-54 MeV from a global fit to inclusive B meson decay data, where the first error is experimental, and includes the uncertainty in alpha_s, and the second is an estimate of theoretical uncertainties in the computation. We discuss the implications of the pole mass renormalon in the determination of m_c.