One-loop gg->bb(bar) effects in the main irreducible background to   exclusive H->bb(bar) production at the LHC
  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. 
A.G. Shuvaev, V.A. Khoze, A.D. Martin and M.G. Ryskin