Heavy Quark Production at High Energy

TL;DR

The paper addresses discrepancies between measured heavy-quark production cross sections and fixed-order QCD predictions by developing a resummation framework that captures large corrections in both threshold and high-energy regimes. It combines fixed-order calculations up to $O(\alpha_s^3)$ with high-energy logarithm resummation via $k_T$-factorization and unintegrated gluon densities, yielding a total cross section that includes the leading terms $O(\alpha_s^3)[\alpha_s\ln(s/M^2)]^n$. The analysis finds that threshold resummation is modest at the Tevatron, while high-energy resummation becomes increasingly important at larger energies, with implications for LHC predictions. The work is applied to photoproduction and hadroproduction of heavy flavours, provides analytic estimates, and includes a complete heavy flavour impact-factor calculation in the appendix.

Abstract

We report on QCD radiative corrections to heavy quark production valid at high energy. The formulae presented will allow a matched calculation of the total cross section which is correct at $O(\as^3)$ and includes resummation of all terms of order $\as^3 [\as \ln (s/m^2)]^n$. We also include asymptotic estimates of the effect of the high energy resummation. A complete description of the calculation of the heavy quark impact factor is included in an appendix.