HARD_DECAYS not working for Higgs decays in the SM+EHC model

[elunghi@indiana.edu]

There seems to be a problem with the Higgs-gluon-gluon effective interaction in the model SM+EHC when using HARD_DECAYS.

If I generate "93 93 -> 23 25" in the SM with HARD_DECAYS = 1 correctly generate events decaying the W, Z and H (See Run.dat.SM and logSM).

If I simply replace SM->SM+EHC, the event generation fails with an "Invalid Color Flow" (See Run.dat.SMEHC and logSMEHC). If, after generating the decay tables, I edit by hand the file "Results/Decays/h0" and set the H->gg width to 0, event generation succeeds.

PS1: Note that the problem persists whether I decay or not the taus

PS2: the log files I posted where obtained with Sherpa 2.1.0 on Ubuntu installed on a virtual machine on a mac. I obtain similar results with Sherpa 2.0.0 installed directly on the mac (in this case I have to add MASSIVE[15]=1 or Sherpa won't generate the tau decay table).

PS3: apparently the problem appears even without HARD_DECAYS. In fact, the same error appears if I try to generate events in which the Higgs is explicitly decayed to gg in SM+EHC. See the Run.dat.SMEHC.direct