gcowan / RapidSim

Phase space generation of b hadron decays
MIT License
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Negative IP value with LHCbGenericIP #49

Open willpietrak opened 5 years ago

willpietrak commented 5 years ago

Dear RapidSim experts,

I generate decays of the form D*+ -> (D0->h+h-)pi+ and I use Momentum and IP Smearing (LHCbGeneric + LHCbGenericIP). When looking at the distributions of (IP_true - IP) of the daughter particles, I see a beautiful (and surely) gaussian distribution telling me that the IP smearing is well done. However, this leads to the fact the IP values of my daughter particles can become negative (which is not physical of course). On Mattermost, Daniel told me that it should be safe to take the absolute value of the smeared IP value. I will try to check if this is the right approach.