cms.EDProducer("SimHitTPAssociationProducer",\ 
    simHitSrc = cms.VInputTag("g4SimHits:TrackerHitsPixelBarrelLowTof", "g4SimHits:TrackerHitsPixelEndcapLowTof"),\ 
    trackingParticleSrc = cms.InputTag("mix","MergedTrackTruth")\ 
)\