These processes represent the production of a Higgs boson in association with a pair of top quarks. The calculation can be performed at LO only.
For process 640, neither the top quarks nor the Higgs boson decays. In processes 641-647, the top quarks are always produced on-shell, which is a necessity for a gauge invariant result from this limited set of diagrams. Switching zerowidth from .true. to .false. only affects the Higgs and the W bosons from the top quark decay. In process 641 both the top quarks decay leptonically and the Higgs boson decays into a pair of bottom quarks. Consistency with the simpler process (640) can be demonstrated by running process 641 with removebr set to true. In process 644 the top quark decays leptonically and the anti-top quark decays hadronically and the Higgs boson decays into a pair of bottom quarks. In process 647 the anti-top quark decays leptonically and the top quark decays hadronically and the Higgs boson decays into a pair of bottom quarks.
Processes 651–657 correspond to processes 641–647 but with the Higgs decaying to two photons. Processes 661–667 correspond to processes 641–647 but with the Higgs decaying to two W-bosons which subsequently decay leptonically.
nplotter˙auto.f is the default plotting routine.