One-loop gg->bb(bar) effects in the main irreducible background to exclusive H->bb(bar) production at the LHC

TL;DR

This paper calculates the one-loop QCD effects on gg->bb̄ production, showing that these effects reduce the background for the Higgs to bb̄ decay at the LHC, which is crucial for Higgs detection.

Contribution

It provides the first detailed calculation of one-loop gg->bb̄ effects in the specific color and angular momentum state relevant for Higgs background suppression.

Findings

One-loop QCD corrections decrease the gg->bb̄ background at the LHC.

Infrared divergences are properly canceled with a realistic cutoff.

The results impact the estimation of the irreducible background for Higgs searches.

Abstract

We calculate the amplitude of gg->bb(bar) production for the colour singlet, J_z=0 di-gluon state at O(\alpha_S^2) order. We consider the cancellation, and a realistic cutoff, of the infrared divergent terms. We show that the one-loop radiative QCD contributions effectively reduce the Born level result for the central exclusive bb(bar) cross section at the LHC. This process is essentially the only irreducible QCD background to the exclusive H->bb(bar) signal.