A complete O(alpha_S^2) calculation of the signal-background interference for the Higgs diphoton decay channel

We present the full \({\cal O}(\as^2)\) computation of the interference effects between the Higgs diphoton signal and the continuum background at the LHC. While the main contribution to the interference originates on the \(gg\) partonic subprocess, we find that the corrections from the \(qg\) and \(q\bar{q}\) channels amount up to 35% of it. We discuss the effect of these new subprocesses in the shift of the diphoton invariant mass peak recently reported by S. Martin in Ref.\cite{Martin:2012xc}.