Correlator of the quark scalar currents and Γ_{tot}(H --> hadrons) at O(α_s^3) in pQCD

TL;DR

The paper computes the massless four-loop O(alpha_s^3) corrections to the correlator of quark scalar currents and to the Higgs decay rate into hadrons within pQCD. By formulating the problem in terms of the scalar-current two-point function and its RG equation, the authors leverage infrared rearrangement and the R*-operation to reduce four-loop UV counterterm calculations to lower-loop p-integrals, enabling an analytic determination of the anomalous dimension gamma^SS_q and the absorptive part R^S(s). They provide explicit color-structured expressions for gamma^SS_q and R^S(s), and obtain the SU(3) results with mu^2 = s, including nf-dependent terms, culminating in a precise MSbar expansion for Gamma(H->bb) up to O(alpha_s^3). Numerically, the O(alpha_s^3) correction is modest but non-negligible for intermediate Higgs masses, improving the reliability of Higgs decay predictions and illustrating the effectiveness of the IRR/R*-operation approach for high-loop QCD calculations.

Abstract

We present the results of the analytical evaluation of the massless four-loop O(alpha_s^3) correction to the correlator of the quark scalar currents and the Higgs decay rate into hadrons.