void 
runMCEvtMix(){
   // ----  Load libraries   -------------------------------------------------
  gROOT->LoadMacro("$VMCWORKDIR/gconfig/basiclibs.C");
  basiclibs();
  gSystem->Load("libGeoBase");
  gSystem->Load("libParBase");
  gSystem->Load("libBase");
  gSystem->Load("libPndData");
  gSystem->Load("libField");
  gSystem->Load("libGen");
  gSystem->Load("libPassive");
  gSystem->Load("libtpc");
  gSystem->Load("libgenfit");
  gSystem->Load("libtrackrep");
  gSystem->Load("libMvd");
  gSystem->Load("libMvdReco");
  // ------------------------------------------------------------------------


  // ========================================================================
  // Verbosity level (0=quiet, 1=event level, 2=track level, 3=debug)
  Int_t iVerbose = 1;

  // Input file (Signals events)
  TString inFile="../data/pions/test1.mc.root";
  TString jobname="mcevtmix2";
  TString inDir=inFile(0,inFile.Last('/')+1);

  TString jobDir=inDir; jobDir+=jobname; jobDir+="/";
  TString cmd="mkdir ";
  cmd+=jobDir; 
  if(gSystem->Exec(cmd)){
    std::cout<<"Could not create Job-Directory "<<jobDir
	     <<". Aborting."<<std::endl;
    return;
  }
  
  TString outFile = inFile; 
  outFile.ReplaceAll(inDir,jobDir);
  outFile.ReplaceAll(".mc.root",".mix.root");

  TString paramIn = inFile;
  paramIn.ReplaceAll(".mc.root",".param.root");
  TString paramOut = outFile;
  paramOut.ReplaceAll(".mix.root",".param.root");

  TString bkgFile = "../data/DPM/test1.mc.root";

std::cout<<"Input: "<<inFile<<std::endl;
std::cout<<"Output: "<<outFile<<std::endl;
std::cout<<"Bkg: "<<bkgFile<<std::endl;
std::cout<<"ParamIn: "<<paramIn<<std::endl;
std::cout<<"ParamOut: "<<paramOut<<std::endl;



  // Number of events to process
  Int_t nEvents = 500;


  // -----   Timer   --------------------------------------------------------
  TStopwatch timer;
  timer.Start();
  // ------------------------------------------------------------------------



  // -----   Digitization run   -------------------------------------------
  FairRunAna *fRun= new FairRunAna();
  fRun->SetInputFile(inFile);
  fRun->SetOutputFile(outFile);
  // ------------------------------------------------------------------------



  // -----  Parameter database   --------------------------------------------
  FairRuntimeDb* rtdb = fRun->GetRuntimeDb();
  FairParRootFileIo* parInput1 = new FairParRootFileIo();
  parInput1->open(paramIn.Data());
  FairParAsciiFileIo* parInput2 = new FairParAsciiFileIo();
  TString tpcDigiFile = gSystem->Getenv("VMCWORKDIR");
  tpcDigiFile += "/tpc/tpc.par";
  parInput2->open(tpcDigiFile.Data(),"in");

  rtdb->setFirstInput(parInput2);
  rtdb->setSecondInput(parInput1);

  FairParRootFileIo* parOutput1 = new FairParRootFileIo(kTRUE);
  parOutput1->open(paramOut.Data());
  rtdb->setOutput(parOutput1);
  rtdb->saveOutput();
  
  fRun->LoadGeometry();
  // ------------------------------------------------------------------------
  
//  GenfitTask *Genfit= new GenfitTask();
//  fRun->AddTask(Genfit);

// ------ QAplots
  //QAPlotCollection* qa=new QAPlotCollection("TpcEvtMixQAPlots");


// ----- PndTpc Event Mixer: Mixes background tracks to events -------------

  PndTpcMCEvtMixTask* evtmixer = new PndTpcMCEvtMixTask();
  evtmixer->SetBkgFileName(bkgFile);
  evtmixer->SetNBkgEvts(1000);
  evtmixer->SetEvtRate(1E7);
  evtmixer->SetPersistence(); // write out time info
  fRun->AddTask(evtmixer);

  // ---- Add MVD Digi for physics event
  
  PndMvdIdealRecoTask* mvdirec = new PndMvdIdealRecoTask(0.01,0.01,0.005);
  mvdirec->SetVerbose(iVerbose);
  fRun->AddTask(mvdirec);


  // -----   Intialise and run   --------------------------------------------
  fRun->Init();

  //rtdb->print();

  fRun->Run(0,nEvents);
  // ------------------------------------------------------------------------


  // -----   Finish   -------------------------------------------------------
  //FairRootManager::Instance()->GetOutFile()->mkdir("QAPlots");
  //FairRootManager::Instance()->GetOutFile()->cd("QAPlots");
  //qa->Write();


 rtdb->saveOutput();
 //rtdb->print();

  timer.Stop();
  Double_t rtime = timer.RealTime();
  Double_t ctime = timer.CpuTime();
  cout << endl << endl;
  cout << "Macro finished succesfully." << endl;
  cout << "Output file is "    << outFile << endl;
  cout << "Parameter file is " << paramOut << endl;
  cout << "Real time " << rtime << " s, CPU time " << ctime << " s" << endl;
  cout << endl;
  // ------------------------------------------------------------------------


}