Power Counting in Dimensionally Regularized NRQCD
read the original abstract
We present a scheme for calculating in NRQCD with consistent power counting in the heavy quark velocity v. As an example, we perform the systematic matching of an external current onto NRQCD at subleading order in v, a calculation relevant for the process e^+e^- -> hadrons near threshold. Consistent velocity power counting in dimensional regularization is achieved by including two distinct gluon fields, one corresponding to gluon radiation and one corresponding to an instantaneous potential. In this scheme power counting is manifest in any gauge, and also holds for non-gauge interactions. The matching conditions for an external vector current in NRQCD are calculated to O(g^2 v^2) and the cancellation of infrared divergences in the matching conditions is shown to require both gluon fields. Some subtleties arising in the matching conditions at subleading order are addressed.
This paper has not been read by Pith yet.
Forward citations
Cited by 1 Pith paper
-
Semi-analytical results for $e^+e^-\to J/\psi + X_{{\rm non\,}c\bar{c}}$ up to $\mathcal{O}(\alpha_s v^2)$ at B factories
NRQCD calculation of O(α_s), O(v²) and first-time O(α_s v²) corrections to e⁺e⁻ → J/ψ + X_non c c̄, with r = m_c/√s expansions to r⁴⁰, yielding cross section 0.530 pb consistent with Belle but angular parameter deviating >2σ.
discussion (0)
Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.