AliGenerator *AddMCGenHijing()
{  
// User defined generator  
  gSystem->Load("liblhapdf.so");      // Parton density functions
  gSystem->Load("libEGPythia6.so");   // TGenerator interface
  gSystem->Load("libpythia6.so");     // Pythia
  gSystem->Load("libAliPythia6.so");  // ALICE specific implementations
  gSystem->Load("libhijing");       
  gSystem->Load("libTHijing");
  AliGenHijing* gener = new AliGenHijing(-1);
  // centre of mass energy 
  gener->SetEnergyCMS(2760.);
  gener->SetImpactParameterRange(0, 20);  
  // reference frame
  gener->SetReferenceFrame("CMS");
  // projectile
  gener->SetProjectile("A", 208, 82);
  gener->SetTarget    ("A", 208, 82);
  // tell hijing to keep the full parent child chain
  gener->KeepFullEvent();

  // enable shadowing
  gener->SetShadowing(1);
  // Don't track spectators
  gener->SetSpectators(0);
  // kinematic selection
  gener->SetSelectAll(0);   

  gener->SetJetQuenching(0);   
  gener->SetPtHardMin (2.3);
  return gener;
}