StRoot: StJetMaker/towers/StjTowerEnergyToTLorentzVector.cxx Source File

00001 // $Id: StjTowerEnergyToTLorentzVector.cxx,v 1.1 2008/11/27 07:35:33 tai Exp $
00002 // Copyright (C) 2008 Tai Sakuma <sakuma@bnl.gov>
00003 #include "StjTowerEnergyToTLorentzVector.h"
00004 
00005 #include "StjTowerEnergyList.h"
00006 
00007 ClassImp(StjTowerEnergyToTLorentzVector)
00008 
00009 TLorentzVector StjTowerEnergyToTLorentzVector::operator()(const StjTowerEnergy& deposit)
00010 {
00011   TVector3 towerLocation;
00012   towerLocation.SetPtEtaPhi(deposit.towerR, deposit.towerEta, deposit.towerPhi); 
00013   TVector3 vertex(deposit.vertexX, deposit.vertexY, deposit.vertexZ);
00014 
00015   TVector3 momentum = towerLocation - vertex;
00016 
00017   double pMag = (deposit.energy > _mass) ? sqrt(deposit.energy*deposit.energy - _mass*_mass) : deposit.energy;
00018 
00019   momentum.SetMag(pMag);
00020   TLorentzVector ret(momentum.x(), momentum.y(), momentum.z(), deposit.energy);
00021   return ret;
00022 }