EXPERT ROOT

void BeamDet_sim(Int_t nEvents = 100){

  //---------------------Files-----------------------------------------------

  TString outFile= "sim1.root";

  TString parFile= "par1.root";

  // ------------------------------------------------------------------------

  // -----   Timer   --------------------------------------------------------

  TStopwatch timer;

  timer.Start(); 

  // ----

  // -----   Create simulation run   ----------------------------------------

  FairRunSim* run = new FairRunSim();

/** Select transport engine

* TGeant3

* TGeant4

**/

  run->SetName("TGeant4");              // Transport engine

  run->SetOutputFile(outFile.Data());          // Output file

// ------------------------------------------------------------------------

// -----   Runtime database   ---------------------------------------------

  FairRuntimeDb* rtdb = run->GetRuntimeDb();

// ------------------------------------------------------------------------

// -----   Create media   -------------------------------------------------

  run->SetMaterials("media.geo");       // Materials

// ------------------------------------------------------------------------

  //-------- Set MC event header --------------------------------------------

  ERMCEventHeader* header = new ERMCEventHeader();

  run->SetMCEventHeader(header);

  //---------------------------------

  // -----   Create detectors  ----------------------------------------------

  FairModule* cave= new ERCave("CAVE");

  cave->SetGeometryFileName("cave.geo");

  run->AddModule(cave);

  // Det definition

  /* Select verbosity level

   * 0 - only standard logs

   * 1 - Print points after each event

  */

  Int_t verbose = 0;

  ERBeamDet* beamDet= new ERBeamDet("ERBeamDet", kTRUE,verbose);

  beamDet->SetGeometryFileName("beamdet.v3.geo_2.root");

  beamDet->SetIonPID(1000160280);

  run->AddModule(beamDet);

 // FairModule* target = new ERTarget("BeamDetTarget", kTRUE, 1);

  //target->SetGeometryFileName("target.h.geo.root");

  //run->AddModule(target);

  // ---------------.q

  //--------------------------------------------------------

  // -----   Create PrimaryGenerator   --------------------------------------

  FairPrimaryGenerator* primGen = new FairPrimaryGenerator();

  //Ion 28S

  Int_t A = 28;

  Int_t Z = 16;

  Int_t Q = 16;

  ERIonMixGenerator* generator = new ERIonMixGenerator("28S", Z, A, Q, 1);

  Double32_t kin_energy = 40 * 1e-3 * 28; //GeV

  //generator->SetKinESigma(kin_energy, 0);

  generator->SetPSigma(6.7835, 6.7835*0.003);

//  generator->SetKinESigma(kin_energy, 0);

  /*

   * Set flag to spread corrdinates parameters on target and reconstruct   

   * coordinates of beam start by received values 

  */

  generator->SpreadingOnTarget();

  Double32_t theta = 0;

  Double32_t sigmaTheta = 0.004*TMath::RadToDeg();

  generator->SetThetaSigma(theta, sigmaTheta);

  generator->SetPhiRange(0, 360);

  Double32_t distanceToTarget = 1533;

  Double32_t sigmaOnTarget = 0.5;

  generator->SetSigmaXYZ(0, 0, -distanceToTarget, sigmaOnTarget, sigmaOnTarget);

  //generator->SetBoxXYZ(-0.4,-0.4,0.4,0.4, -distanceToTarget);

  generator->AddBackgroundIon("26P", 15, 26, 15, 0.25);

  generator->AddBackgroundIon("26S", 16, 26, 16, 0.25);

  generator->AddBackgroundIon("24Si", 14, 24, 14, 0.25);

  primGen->AddGenerator(generator);

  run->SetGenerator(primGen);

  // ------------------------------------------------------------------------

  //-------Set visualisation flag to true------------------------------------

  run->SetStoreTraj(kTRUE);

  //-------Set LOG verbosity  -----------------------------------------------

  FairLogger::GetLogger()->SetLogVerbosityLevel("LOW");

  // —– Initialize simulation run ———————————— 

  run->Init();

  Int_t nSteps = -15000;

  // —– Runtime database ——————————————— 

  Bool_t kParameterMerged = kTRUE; 

  FairParRootFileIo* parOut = new FairParRootFileIo(kParameterMerged);

  parOut->open(parFile.Data()); 

  rtdb->setOutput(parOut); 

  rtdb->saveOutput(); 

  rtdb->print(); // 

  // -----   Run simulation  ------------------------------------------------

    run->Run(nEvents);

    // -----   Finish   -------------------------------------------------------

    timer.Stop();

    Double_t rtime = timer.RealTime();

    Double_t ctime = timer.CpuTime();

    cout << endl << endl;

    cout << "Macro finished succesfully." << endl;

    cout << "Output file is sim.root" << endl;

    cout << "Parameter file is par.root" << endl;

    cout << "Real time " << rtime << " s, CPU time " << ctime

                    << "s" << endl << endl;

   // cout << "Energy " << momentum << "; mass " << mass << endl; 

}