run_sim_tpccombi(Int_t nEvents=10){
  TStopwatch timer;
  timer.Start();
  gDebug=0;
  // Load basic libraries
  // If it does not work,  please check the path of the libs and put it by hands
  gROOT->LoadMacro("$VMCWORKDIR/gconfig/rootlogon.C");
  rootlogon();
  
  TString digiFile = "all.par";
  TString parFile = "params_tpccombi.root";
  
  FairRunSim *fRun = new FairRunSim();

  // set the MC version used
  // ------------------------

  fRun->SetName("TGeant3");
  //fRun->SetName("TGeant4");

  fRun->SetOutputFile("points_tpccombi.root");

  // Set the parameters
  //-------------------------------
  TString allDigiFile = gSystem->Getenv("VMCWORKDIR");
  allDigiFile += "/macro/params/";
  allDigiFile += digiFile;
 
  FairRuntimeDb* rtdb = fRun->GetRuntimeDb();
  FairParAsciiFileIo* parIo1 = new FairParAsciiFileIo();
  parIo1->open(allDigiFile.Data(),"in");
  rtdb->setFirstInput(parIo1);        
  Bool_t kParameterMerged=kTRUE;
	
  FairParRootFileIo* output=new FairParRootFileIo(kParameterMerged);
  output->open(parFile);
  rtdb->setOutput(output);
  
  // Set Material file Name
  //-----------------------
  fRun->SetMaterials("media_pnd.geo");

  // Create and add detectors
  //-------------------------
  FairModule *Cave= new PndCave("CAVE");
  Cave->SetGeometryFileName("pndcave.geo");
  fRun->AddModule(Cave); 

  FairModule *Magnet= new PndMagnet("MAGNET");
  //Magnet->SetGeometryFileName("FullSolenoid_V842.root");
  Magnet->SetGeometryFileName("FullSuperconductingSolenoid_v831.root");
  fRun->AddModule(Magnet);
  
  FairModule *Dipole= new PndMagnet("MAGNET");
  Dipole->SetGeometryFileName("dipole.geo");
  fRun->AddModule(Dipole);

  FairModule *Pipe= new PndPipe("PIPE");
  //fRun->AddModule(Pipe);

   FairDetector *Tpc = new PndTpcDetector("TPC", kTRUE);
  Tpc->SetGeometryFileName("tpc.geo");
  fRun->AddModule(Tpc);

  FairDetector *Mvd = new PndMvdDetector("MVD", kTRUE);
  //  Mvd->SetGeometryFileName("MVD_v1.0_woPassiveTraps.root");
  Mvd->SetGeometryFileName("Mvd-2.1_AddDisks_FullVersion");
  fRun->AddModule(Mvd);

  PndEmc *Emc = new PndEmc("EMC",kTRUE);
  Emc->SetGeometryVersion(15);
  Emc->SetStorageOfData(kFALSE);
  fRun->AddModule(Emc);

  FairDetector *Tof = new PndTof("TOF",kTRUE);
  Tof->SetGeometryFileName("tofbarrel.geo");
  fRun->AddModule(Tof);

  FairDetector *FTof = new PndFtof("FTOF",kTRUE);
  FTof->SetGeometryFileName("ftofwall.root");
  fRun->AddModule(FTof);
  
  PndMdt *Muo = new PndMdt("MDT",kTRUE);
  Muo->SetBarrel("fast");
  Muo->SetEndcap("fast");
  Muo->SetMuonFilter("fast");
  Muo->SetMdtMagnet(kTRUE);
  Muo->SetMdtMFIron(kTRUE);
  fRun->AddModule(Muo);

  FairDetector *Gem = new PndGemDetector("GEM", kTRUE);
  Gem->SetGeometryFileName("gem_3Stations.root");
  fRun->AddModule(Gem);

  PndDsk* Dsk = new PndDsk("DSK", kTRUE);
  Dsk->SetGeometryFileName("dsk.root");
  Dsk->SetStoreCerenkovs(kFALSE);
  Dsk->SetStoreTrackPoints(kFALSE);
  fRun->AddModule(Dsk);

  PndDrc *Drc = new PndDrc("DIRC", kTRUE);
  Drc->SetRunCherenkov(kFALSE); // for fast sim Cherenkov -> kFALSE
  fRun->AddModule(Drc);
  
  // Create and Set Event Generator
  //-------------------------------

  FairPrimaryGenerator* primGen = new FairPrimaryGenerator();
  fRun->SetGenerator(primGen);

  /// reading events from file or...
  // FairEvtGenGenerator* evtGen = new FairEvtGenGenerator("output.evt");
  // primGen->AddGenerator(evtGen);

  /// ... generate your signal on the fly
  PndEvtGenDirect *EvtGen = new PndEvtGenDirect("psi(2S)","PSI2S.DEC");
  EvtGen->SetStoreTree();
  primGen->AddGenerator(EvtGen);

  /// for background
//  Float_t mom = 6.991;
//  PndDpmDirect *Dpm= new PndDpmDirect(mom,0);
//  primGen->AddGenerator(Dpm);

  // Create and Set Magnetic Field
  //-------------------------------
  fRun->SetBeamMom(15);
  PndMultiField *fField= new PndMultiField("FULL");
  fRun->SetField(fField);

  // EMC Hit producer
  //-------------------------------
  PndEmcHitProducer* emcHitProd = new PndEmcHitProducer();
  fRun->AddTask(emcHitProd);

  //-------------------------- switch on the vis manager-----------//
  fRun->SetStoreTraj(kTRUE);
  
  /**Initialize the session*/
  fRun->Init();

  //----------------- Set some cuts for the visualization-----------
  FairTrajFilter* trajFilter = FairTrajFilter::Instance();
  // Set cuts for storing the trajectpries
  trajFilter->SetStepSizeCut(0.04); // 1 cm
  //     trajFilter->SetVertexCut(-2000., -2000., 4., 2000., 2000., 100.);
  //     trajFilter->SetMomentumCutP(10e-3); // p_lab > 10 MeV
  //     trajFilter->SetEnergyCut(0., 1.02); // 0 < Etot < 1.04 GeV
  trajFilter->SetStorePrimaries(kTRUE);
  trajFilter->SetStoreSecondaries(kTRUE);
  //-------------------------  Run the Simulation  -----------------
  
  rtdb->setOutput(output);
  rtdb->saveOutput();
  rtdb->print();

  // Transport nEvents
  // -----------------
  fRun->Run(nEvents);

  timer.Stop();

  Double_t rtime = timer.RealTime();
  Double_t ctime = timer.CpuTime();
  printf("RealTime=%f seconds, CpuTime=%f seconds\n",rtime,ctime);

}