thailand2017/tut_fastsim.C

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// *******
// Tutorial Macro for running fast simulation 
// *******

// The parameters are
// -------------------
// USAGE:\n";
// tut_fastsim.C+( [nevt], [prefix], [decfile], [mom], [res] )
//    [nevt]     : number of events; default = 1000
//    [pref]     : prefix for output
//    [decfile]  : decfile; 'DPM'/'FTF' uses DPM/FTF generator instead
//    [mom]      : pbar momentum
//    [res]      : resonance (ignored when running DPM); default = 'pbarpSystem0'


void tut_fastsim(Int_t nEvents = 1000, TString prefix = "signal", TString Decfile="pp_jpsi2pi_jpsi_mumu.dec", Float_t Mom=6.232, TString Resonance="pbarpSystem" )
{
        // if Mom<0, interprete as -E_cm -> compute mom
        double mp = 0.938272;
        if (Mom<0)
        {
                double X = (Mom*Mom-2*mp*mp)/(2*mp);
                Mom = sqrt(X*X-mp*mp);
        }
        
        // Allow shortcut for resonance
        if (Resonance=="pbp")  Resonance = "pbarpSystem";
        if (Resonance=="pbp0") Resonance = "pbarpSystem0";

        // Prevent generator from throwing a lot of warnings
        TLorentzVector fIni(0,0,Mom,mp+sqrt(Mom*Mom+mp*mp));
        TDatabasePDG::Instance()->AddParticle("pbarpSystem","pbarpSystem",fIni.M(),kFALSE,0.1,0, "",88888,0);
        TDatabasePDG::Instance()->AddParticle("pbarpSystem0","pbarpSystem0",fIni.M(),kFALSE,0.1,0, "",88880,0);
                
        //----- Switches for Simulation Options ------------------------------
        Bool_t enableSplitoff    = true;  // create e.-m. and hadronic split offs
        Bool_t mergeNeutrals     = true;  // merge neutrals (for merged pi0s)
        Bool_t electronBrems     = true;  // bremsstrahlung loss for electrons 
        
        //----- Presist simulation output ------------------------------
        Bool_t persist           = true;  

        //-----General settings-----------------------------------------------
        TString BaseDir =  gSystem->Getenv("VMCWORKDIR");
        TString splitpars = BaseDir+"/fsim/splitpars.dat";
        gRandom->SetSeed();

        //-----User Settings:-------------------------------------------------
        TString OutputFile = prefix+"_fast.root";
        
        gDebug             = 0;

        // choose your event generator
        Bool_t UseEvtGenDirect  = kTRUE;
        Bool_t UseDpm           = kFALSE;

        // use DPM generator; default: inelastic @ pbarmom = mom
        if (Decfile.BeginsWith("DPM"))
        {
                UseEvtGenDirect = kFALSE;
                UseDpm          = kTRUE;
        }

        // Start a stop watch
        TStopwatch timer;
        timer.Start();

        // Create the Simulation run manager
        // --------------------------------
        FairRunSim *fRun = new FairRunSim();
        fRun->SetOutputFile(OutputFile.Data());
        fRun->SetWriteRunInfoFile(kFALSE);

        FairLogger::GetLogger()->SetLogToFile(kFALSE);

        // -------------------------------
        // Create and Set Event Generator
        // -------------------------------
        //FairFilteredPrimaryGenerator* primGen = new FairFilteredPrimaryGenerator();
        FairPrimaryGenerator* primGen = new FairPrimaryGenerator();
        fRun->SetGenerator(primGen);
        fRun->SetName("TGeant3");

        if(UseDpm)
        {
                int mode = 0;
                if (Decfile=="DPM1") mode = 1;
                if (Decfile=="DPM2") mode = 2;
                
                PndDpmDirect *Dpm= new PndDpmDirect(Mom,mode);  // 0 = inelastic, 1 = inelastic & elastic, 2 = elastic
                Dpm->SetUnstable(111);   // pi0
                Dpm->SetUnstable(310);   // K_S0
                Dpm->SetUnstable(3122);  // Lambda
                Dpm->SetUnstable(-3122); // anti-Lambda
                Dpm->SetUnstable(221);   // eta
                primGen->AddGenerator(Dpm);
        }

        if(UseEvtGenDirect)
        {
                PndEvtGenDirect *EvtGen = new PndEvtGenDirect(Resonance, Decfile.Data(), Mom);
                EvtGen->SetStoreTree(kTRUE);
                primGen->AddGenerator(EvtGen);
        }

        // ------------- switch off the transport of particles
        primGen->DoTracking(kFALSE);

        //---------------------Create and Set the Field(s)----------
        PndMultiField *fField= new PndMultiField("AUTO");
        fRun->SetField(fField);

        
        // ***********************************
        // Setup the Fast Simulation Task
        // ***********************************

        PndFastSim* fastSim = new PndFastSim(persist);
                
        // increasing verbosity increases the amount of console output (mainly for debugging)
        fastSim->SetVerbosity(0);

        // enable the merging of neutrals if they have similar direction
        //-----------------------------
        fastSim->MergeNeutralClusters(mergeNeutrals);

        // enable bremsstahlung loss for electrons
        //-----------------------------
        fastSim->EnableElectronBremsstrahlung(electronBrems);

        //enable the producting of parametrized neutral (hadronic) split offs
        // generate electro-magnetic / hadronic split offs in the EMC? switch off when running w/o EMC

        if (enableSplitoff)     fastSim->EnableSplitoffs(splitpars.Data());

        fastSim->SetUseFlatCov(true);
        
        // -----------------------------------------------------------------------------------
        // Tracking: Set up in parts of theta coverage. All modelled by PndFsmSimpleTracker.
        // Mind: Numbers on resolution (pRes,thtRes,phiRes) and efficiency are guessed
        // -----------------------------------------------------------------------------------
        
        // - (Full Panda Tracking: STT MVD GEM FTS)

        fastSim->AddDetector("ScSttAlone",  "thtMin=145.  thtMax=159.5 ptmin=0.1 pmin=0.0 pRes=0.04 thtRes=0.006 phiRes=0.007 efficiency=0.25");
        fastSim->AddDetector("ScSttMvd",    "thtMin=20.9  thtMax=145.  ptmin=0.1 pmin=0.0 pRes=0.02 thtRes=0.001 phiRes=0.001 efficiency=0.85");
        fastSim->AddDetector("ScSttMvdGem", "thtMin=7.8   thtMax=20.9  ptmin=0.1 pmin=0.0 pRes=0.02 thtRes=0.001 phiRes=0.001 efficiency=0.85");
        fastSim->AddDetector("ScMvdGem",    "thtMin=5.    thtMax=7.8   ptmin=0.1 pmin=0.0 pRes=0.03 thtRes=0.001 phiRes=0.001 efficiency=0.60");

        // Fwd spectrometer enabled -> use Fwd tracking system
        fastSim->AddDetector("ScFts",       "thtMin=0.    thtMax=5.    ptmin=0.0 pmin=0.5 pRes=0.05  thtRes=0.002 phiRes=0.002 efficiency=0.80");

        // -----------------------------------------------------------------------------------
        // Vertexing
        // -----------------------------------------------------------------------------------

        // MVD and GEM are enabled -> better vertexing in central region
        fastSim->AddDetector("ScVtxMvd",   "thtMin=5. thtMax=145. ptmin=0.1 vtxRes=0.005 efficiency=1."); // efficiency=1: all tracks found in trackers will get a vertex information
        fastSim->AddDetector("ScVtxNoMvd", "thtMin=0. thtMax=5.   ptmin=0.0 vtxRes=0.05  efficiency=1."); // efficiency=1: all tracks found in trackers will get a vertex information

        // -----------------------------------------------------------------------------------
        // EM Calorimeters w/ default parameters
        // (don't have to be set, just to list the available parameters
        // -----------------------------------------------------------------------------------

        fastSim->AddDetector("EmcFwCap", "thtMin=10.0 thtMax=22.0 Emin=0.01 dist=2.5");
        fastSim->AddDetector("EmcBwCap", "thtMin=142.0 thtMax=160.0 Emin=0.01 dist=0.7");

        // EmcBarrel also allows to set phiMin and phiMax and can be added multiple times as EmcBarrel1, EmcBarrel2, etc.
        // Should be made constistent with EmcPidBarrel below
        fastSim->AddDetector("EmcBarrel","thtMin=22.0 thtMax=142.0 Emin=0.01 barrelRadius=0.5");

        // Fwd spectrometer enabled -> use Fwd EMC
        fastSim->AddDetector("EmcFS",    "thtMin=0.05 thtMax=10.0 aPar=0.013 bPar=0.0283 Emin=0.01 dist=8.2");

        // -----------------------------------------------------------------------------------
        // PID
        // -----------------------------------------------------------------------------------

        // PID detectors being always in: STT, MUO Barrel, EMC FwdCap, EMC BwdCap
        //Note: A dEdX parametrization from 2008
        fastSim->AddDetector("SttPid","thtMin=7.8 thtMax=159.5 ptmin=0.1 dEdxRes=0.15 efficiency=1.");
        fastSim->AddDetector("ScMdtPidBarrel", "thtMin=10.0 thtMax=130.0 pmin=0.5 efficiency=0.95 misId=0.01");
        fastSim->AddDetector("ScEmcPidFwCap",  "thtMin=10.0  thtMax=22.0  ptmin=0.0 pmin=0.0 efficiency=1.0");
        fastSim->AddDetector("ScEmcPidBwCap",  "thtMin=142.0 thtMax=160.0  ptmin=0.0 pmin=0.0 efficiency=1.0");

        // MVD and GEM are enabled -> MVD PID available
        //Note: A Bethe-Bloch-Landau-Gauss Prametrization from 2008
        fastSim->AddDetector("MvdPid","thtMin=5.  thtMax=133.6 ptmin=0.1  dEdxResMulti=1. efficiency=1.");

        // EMC Barrel enable -> EMC barrel PID available
        fastSim->AddDetector("ScEmcPidBarrel", "thtMin=22.0  thtMax=142.0 ptmin=0.2 pmin=0.0 efficiency=1.0");

        // Barrel DIRC enabled
        fastSim->AddDetector("DrcBarrel","thtMin=22.0 thtMax=140.0 dthtc=0.01 nPhotMin=5 effNPhotons=0.075");

        // Disc DIRC enabled
        fastSim->AddDetector("DrcDisc","thtMin=5.0 thtMax=22.0 dthtc=0.01 nPhotMin=5 effNPhotons=0.075");

        // Fwd spectrometer enabled -> use RICH, FwdMUO and EMC FS
        fastSim->AddDetector("ScEmcPidFS",     "thtMin=0.5   thtMax=10.0  ptmin=0.0 pmin=0.5 efficiency=1.0");
        fastSim->AddDetector("Rich","angleXMax=5.0 angleYMax=10.0 dthtc=0.01 nPhotMin=5 effNPhotons=0.075");
        fastSim->AddDetector("ScMdtPidForward","thtMin=0.0  thtMax=10.0  pmin=0.5 efficiency=0.95 misId=0.01");


        fRun->AddTask(fastSim);
                
        //-------------------------  Initialize the RUN  -----------------
        fRun->Init();
        
        //-------------------------  Run the Simulation  -----------------
        fRun->Run(nEvents);
        
        
        //------------------------Print some info and exit----------------
        timer.Stop();
        Double_t rtime = timer.RealTime();
        Double_t ctime = timer.CpuTime();
        printf("RealTime=%f seconds, CpuTime=%f seconds\n",rtime,ctime);
}