on-shell production + decay, cuts and event generation

[fbach]

When I try to produce on-shell top pairs decaying into semileptonic final states together with one final state photon (see sindarin file attached), everything integrates fine but the event generation gets stuck as soon as the photon is required to come from a decay branch, at least when existing integrations are reused. Running the sindarin file in a completely clean folder, events are produced in the very first run only, but after switching the photon radiation e.g. from the leptonic to the hadronic branch (or vice versa) and reusing the integrations, the event generation gets stuck again. Same result with charge-conjugated branches or gluon radiation. However, production of decay events (i.e. without ttbar production beforehand) in the various branches always works.

[fbach]

Ok, this seems to be connected with the cuts on decay products rather than any boson radiation: When I just produce top pairs and let them decay while cutting on the decay products (cf. foo2.sin), event generation only works if the sindarin file is executed in a clean environment: e.g. when I run the script in a new folder with cuts commented out (working) and then comment in the cuts and rerun the script, event generations fails. Also, when I first produce stable tops only and then rerun declaring them unstable, event generation only works with cuts commented out, otherwise it gets stuck again.

In any case, even in those cases where event generation works with cut declaration, these cuts are completely ignored in the event generation (cf. analysis output produced by foo2.sin)!

[kilian]

This turns out to be the same issue as #436. Fixed now.