D-meson lifetimes within the heavy quark expansion

TL;DR

This paper investigates D-meson lifetimes using the heavy quark expansion, incorporating NLO QCD and subleading corrections, achieving good agreement with experimental data despite large uncertainties.

Contribution

The study applies the heavy quark expansion to charm decays with NLO QCD and 1/m_c corrections, highlighting its potential validity for D-mesons.

Findings

Good agreement with experimental D-meson lifetime data

Large hadronic uncertainties due to missing lattice inputs

Supports the applicability of HQE to charm decays

Abstract

Even if new data indicate that direct CP violation in D-meson decays is compatible with the standard model expectation, it has triggered a lot of interest, and charm phenomenology will remain an essential part of new physics searches due to its unique role as a probe for flavor-changing neutral currents among up-type quarks. Charm physics poses considerable theoretical challenges, because the charm mass is neither light nor truly heavy. The heavy quark expansion (HQE) provides a perturbative expansion in the inverse heavy quark mass for inclusive rates. It has proved to be very successful in the B sector, yet its validity for charm decays has often been questioned. We present results of a HQE study of D-meson lifetimes including NLO QCD and subleading 1/m_c corrections. We find good agreement with experimental data, but with huge hadronic uncertainties due to missing lattice input for hadronic matrix elements.