These processes represent the production a real photon with a b quark or a c quark Since this process includes a real photon, the cross section diverges when the photon is very soft or in the direction of the beam. Thus in order to produce sensible results, the input file must supply values for both gammptmin and gammrapmax. This will ensure that the cross section is well-defined.
The calculation of process 283–284 is only available at leading order.
nplotter_auto.f is the default plotting routine.