Full top quark mass dependence in Higgs boson pair production at NLO
  We study the effects of the exact top-quark mass dependent two-loop corrections to Higgs boson pair production by gluon fusion at the LHC and at a 100 TeV hadron collider. We perform a detailed comparison of the full next-to-leading order result to various approximations at the level of differential distributions and also analyse non-standard Higgs self-coupling scenarios. We find that the different next-to-leading order approximations differ from the full result by up to 50 percent in relevant differential distributions. This clearly stresses the importance of the full NLO result. 
S.Borowka, N.Greiner, G.Heinrich, S.P.Jones, M.Kerner, J.Schlenk,   T.Zirke
hep-ph