• Q: Is there overlap removal and object selection applied for the default channel ("999" or "DEFAULT")?

• A: We should start saying that "DEFAULT" and "999" flags refer to different things.

The "DEFAULT" flag refers to object selection/overlap removal and it is used to flag particles (jets, electrons, ...). And it means "default cuts defined in SUSYTools/src/SUSYDefinitions.cxx ". All particles passing this default built-in selection/overlap are flagged with this "DEFAULT". You get the "DEFAULT" flag only if you have channels where you don't define "customCuts" keys. Otherwise, if you have only channels with custom selection/overlap you don't get any "DEFAULT" flag for your particles, because no default cuts are used to select particles.

Instead "999" is related to event selection and it is used to flag events. Every event, before event selection loop, is flagged as "999". Then, if the event passes at least all the event selection cuts for one channel, the "999" flag is removed and the event is flagged with the channel name it passed. Thus you cannot have "999" and other flags for the same event. But you can have "DEFAULT" and other flags for the same particle (if you have channels using the default selection/overlap cuts).

If you apply skimming (doSkimmingGlobal = True in the steering file), you will not have any event flagged as "999", because events not passing any channel are skimmed out.

-- RiccardoMariaBianchi - 04 Mar 2009