VSDataFormats - CVS

GenEffParticle?

• This is a class which inherits from GenParticle?
• It also stores a RefToBase? so that you can match it to a reco::Candidate type object
• This allows you to easily do efficiency calculations (it sets up an alias in the tree with the module name that ran it):

Events->Draw("recoElFromZsEff.eta() >> h1","recoElFromZsEff.hasMatch()")
Events->Draw("recoElFromZsEff.eta() >> h2","")
hEff = h1
hEff->Divide(h2)
hEff->Draw()  //Yeah! Easy efficiency!

• There is even a cool GenEffParticleProducer that is currently working but still under development, see VSPhysicsTool/HepMCCandAlgos