We present the two-loop virtual corrections to Standard Model Higgs boson pair production via gluon fusion gg→ HH in the heavy top quark limit. Based on this result, we evaluate the corresponding cross section at the LHC at 14 TeV in the next-to-next-to-leading order soft-virtual approximation. We find an inclusive K-factor of about 2.4, resulting in an increase close to 23% with respect to the previous available calculation at next-to-leading order. As expected, we observe a considerable reduction in the renormalization and factorization scale dependence. © 2013 Elsevier B.V.
de Florian, D., & Mazzitelli, J. (2013). Two-loop virtual corrections to Higgs pair production. Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics, 724(4–5), 306–309. https://doi.org/10.1016/j.physletb.2013.06.046