* provided "as is" without express or implied warranty. *
**************************************************************************/
-// $Id: AliCollider.cxx,v 1.7 2003/10/26 14:53:44 nick Exp $
+// $Id: AliCollider.cxx,v 1.8 2003/12/18 09:28:06 nick Exp $
///////////////////////////////////////////////////////////////////////////
// Class AliCollider
//
// gen->Init("fixt",zp,ap,zt,at,158);
//
+// gen->SetTitle("SPS Pb-Pb collision at 158A GeV/c beam energy");
+//
// Int_t nevents=5;
//
// AliRandom rndm;
//
// gen->Init("fixt","nu_mu","p",1e11);
//
+// gen->SetTitle("Atmospheric nu_mu-p interaction at 1e20 eV");
+//
// Int_t nevents=10;
//
// for (Int_t i=0; i<nevents; i++)
//
//
//--- Author: Nick van Eijndhoven 22-nov-2002 Utrecht University
-//- Modified: NvE $Date: 2003/10/26 14:53:44 $ Utrecht University
+//- Modified: NvE $Date: 2003/12/18 09:28:06 $ Utrecht University
///////////////////////////////////////////////////////////////////////////
#include "AliCollider.h"
fEvent=0;
+ fSpecpmin=0;
+
fFrame="none";
fWin=0;
fOutFile=0;
fOutTree=0;
+
+ fSelections=0;
+ fSelect=0;
+
+ TString s=GetName();
+ s+=" (AliCollider)";
+ SetName(s.Data());
}
///////////////////////////////////////////////////////////////////////////
AliCollider::~AliCollider()
delete fOutTree;
fOutTree=0;
}
+ if (fSelections)
+ {
+ delete fSelections;
+ fSelections=0;
+ }
}
///////////////////////////////////////////////////////////////////////////
void AliCollider::SetOutputFile(TString s)
// Generate one event.
// In case of a nucleus-nucleus interaction, the argument 'npt' denotes
// the number of participant nucleons.
+// Normally also the spectator tracks will be stored into the event structure.
+// The spectator tracks have a negative user Id to distinguish them from the
+// ordinary generated tracks.
+// In case the user has selected the creation of vertex structures, the spectator
+// tracks will be linked to the primary vertex.
+// However, specification of npt<0 will suppress the storage of spectator tracks.
+// In the latter case abs(npt) will be taken as the number of participants.
// In case of a standard Pythia run for 'elementary' particle interactions,
// the value of npt is totally irrelevant.
//
// In case of a nucleus-nucleus interaction, the proper A and Z values for
// the projectile and target particles are set in the event structure.
// However, in this case both particle ID's are set to zero.
+//
+// Note : Only in case an event passed the selection criteria as specified
+// via SelectEvent(), the event will appear on the output file.
fEventnum++;
+ Int_t specmode=1;
+ if (npt<0)
+ {
+ specmode=0;
+ npt=abs(npt);
+ }
+
// Counters for the various (proj,targ) combinations : p+p, n+p, p+n and n+n
Int_t ncols[4]={0,0,0,0};
+ Int_t zp=0;
+ Int_t ap=0;
+ Int_t zt=0;
+ Int_t at=0;
+
Int_t ncol=1;
if (fNucl)
{
if (npt%2 && fRan.Uniform()>0.5) ncol+=1;
// Determine the number of the various types of N+N interactions
- Int_t zp=fZproj;
- Int_t ap=fAproj;
- Int_t zt=fZtarg;
- Int_t at=fAtarg;
+ zp=fZproj;
+ ap=fAproj;
+ zt=fZtarg;
+ at=fAtarg;
Int_t maxa=2; // Indicator whether proj (1) or target (2) has maximal A left
if (ap>at) maxa=1;
Float_t* rans=new Float_t[ncol];
{
fEvent=new AliEvent();
fEvent->SetOwner();
+ fEvent->SetName(GetName());
+ fEvent->SetTitle(GetTitle());
}
fEvent->Reset();
AliPosition r,rx;
Float_t v[3];
AliVertex vert;
+ Ali3Vector pproj,ptarg;
if (fVertexmode)
{
Int_t kf=0;
Float_t charge=0,mass=0;
+ char* name="";
Int_t ntypes=4;
}
// Generate all the various collisions
- Int_t first=1; // Flag to indicate the first collision process
+ fSelect=0; // Flag to indicate whether the total event is selected or not
+ Int_t select=0; // Flag to indicate whether the sub-event is selected or not
+ Int_t first=1; // Flag to indicate the first collision process
Double_t pnucl;
Int_t npart=0,ntk=0;
Double_t dist=0;
{
GenerateEvent();
+ select=IsSelected();
+ if (select) fSelect=1;
+
if (first) // Store projectile and target information in the event structure
{
if (fNucl)
v[0]=GetP(1,1);
v[1]=GetP(1,2);
v[2]=GetP(1,3);
- pnucl=sqrt(v[0]*v[0]+v[1]*v[1]+v[2]*v[2]);
+ pproj.SetVector(v,"car");
+ pnucl=pproj.GetNorm();
fEvent->SetProjectile(fAproj,fZproj,pnucl);
v[0]=GetP(2,1);
v[1]=GetP(2,2);
v[2]=GetP(2,3);
- pnucl=sqrt(v[0]*v[0]+v[1]*v[1]+v[2]*v[2]);
+ ptarg.SetVector(v,"car");
+ pnucl=ptarg.GetNorm();
fEvent->SetTarget(fAtarg,fZtarg,pnucl);
}
else
if (medit >= 0) Pyedit(medit); // Define which particles are to be kept
- if (mlist >= 0) Pylist(mlist);
+ if (mlist>=0 && select) Pylist(mlist);
npart=GetN();
for (Int_t jpart=1; jpart<=npart; jpart++)
{
kf=GetK(jpart,2);
charge=Pychge(kf)/3.;
+ Pyname(kf,name);
mass=GetP(jpart,5);
// 3-momentum in GeV/c
t.Reset();
t.SetId(ntk);
t.SetParticleCode(kf);
+ t.SetName(name);
t.SetCharge(charge);
t.SetMass(mass);
t.Set3Momentum(p);
}
}
+ // Include the spectator tracks in the event structure.
+ if (fNucl && specmode)
+ {
+ Float_t pmass=0.938272;
+ Float_t nmass=0.93956533;
+ v[0]=0;
+ v[1]=0;
+ v[2]=0;
+ r.SetPosition(v,"car");
+
+ zp=fZproj-(ncols[0]+ncols[2]);
+ if (zp<0) zp=0;
+ ap=fAproj-(ncols[0]+ncols[1]+ncols[2]+ncols[3]);
+ if (ap<0) ap=0;
+ zt=fZtarg-(ncols[0]+ncols[1]);
+ if (zt<0) zt=0;
+ at=fAtarg-(ncols[0]+ncols[1]+ncols[2]+ncols[3]);
+ if (at<0) at=0;
+
+ Int_t nspec=0;
+
+ if (pproj.GetNorm() > fSpecpmin)
+ {
+ kf=2212; // Projectile spectator protons
+ charge=Pychge(kf)/3.;
+ mass=pmass;
+ Pyname(kf,name);
+ for (Int_t iprojp=1; iprojp<=zp; iprojp++)
+ {
+ nspec++;
+ t.Reset();
+ t.SetId(-nspec);
+ t.SetParticleCode(kf);
+ t.SetName(name);
+ t.SetTitle("Projectile spectator proton");
+ t.SetCharge(charge);
+ t.SetMass(mass);
+ t.Set3Momentum(pproj);
+ t.SetBeginPoint(r);
+
+ fEvent->AddTrack(t);
+ }
+
+ kf=2112; // Projectile spectator neutrons
+ charge=Pychge(kf)/3.;
+ mass=nmass;
+ Pyname(kf,name);
+ for (Int_t iprojn=1; iprojn<=(ap-zp); iprojn++)
+ {
+ nspec++;
+ t.Reset();
+ t.SetId(-nspec);
+ t.SetParticleCode(kf);
+ t.SetName(name);
+ t.SetTitle("Projectile spectator neutron");
+ t.SetCharge(charge);
+ t.SetMass(mass);
+ t.Set3Momentum(pproj);
+ t.SetBeginPoint(r);
+
+ fEvent->AddTrack(t);
+ }
+ }
+
+ if (ptarg.GetNorm() > fSpecpmin)
+ {
+ kf=2212; // Target spectator protons
+ charge=Pychge(kf)/3.;
+ mass=pmass;
+ Pyname(kf,name);
+ for (Int_t itargp=1; itargp<=zt; itargp++)
+ {
+ nspec++;
+ t.Reset();
+ t.SetId(-nspec);
+ t.SetParticleCode(kf);
+ t.SetName(name);
+ t.SetTitle("Target spectator proton");
+ t.SetCharge(charge);
+ t.SetMass(mass);
+ t.Set3Momentum(ptarg);
+ t.SetBeginPoint(r);
+
+ fEvent->AddTrack(t);
+ }
+
+ kf=2112; // Target spectator neutrons
+ charge=Pychge(kf)/3.;
+ mass=nmass;
+ Pyname(kf,name);
+ for (Int_t itargn=1; itargn<=(at-zt); itargn++)
+ {
+ nspec++;
+ t.Reset();
+ t.SetId(-nspec);
+ t.SetParticleCode(kf);
+ t.SetName(name);
+ t.SetTitle("Target spectator neutron");
+ t.SetCharge(charge);
+ t.SetMass(mass);
+ t.Set3Momentum(ptarg);
+ t.SetBeginPoint(r);
+
+ fEvent->AddTrack(t);
+ }
+ }
+
+ // Link the spectator tracks to the primary vertex.
+ if (fVertexmode)
+ {
+ AliVertex* vp=fEvent->GetIdVertex(1);
+ if (vp)
+ {
+ for (Int_t ispec=1; ispec<=nspec; ispec++)
+ {
+ AliTrack* tx=fEvent->GetIdTrack(-ispec);
+ if (tx) vp->AddTrack(tx);
+ }
+ }
+ }
+}
+
if (mlist && !(fEventnum%fPrintfreq)) cout << endl; // Create empty output line after the event
- if (fOutTree) fOutTree->Fill();
+
+ if (fOutTree && fSelect) fOutTree->Fill();
}
///////////////////////////////////////////////////////////////////////////
-AliEvent* AliCollider::GetEvent()
+AliEvent* AliCollider::GetEvent(Int_t select)
{
// Provide pointer to the generated event structure.
- return fEvent;
+//
+// select = 0 : Always return the pointer to the generated event.
+// 1 : Only return the pointer to the generated event in case
+// the event passed the selection criteria as specified via
+// SelectEvent(). Otherwise the value 0 will be returned.
+//
+// By invoking GetEvent() the default of select=0 will be used.
+
+ if (!select || fSelect)
+ {
+ return fEvent;
+ }
+ else
+ {
+ return 0;
+ }
}
///////////////////////////////////////////////////////////////////////////
void AliCollider::EndRun()
}
}
///////////////////////////////////////////////////////////////////////////
+void AliCollider::SelectEvent(Int_t id)
+{
+// Add a particle to the event selection list.
+// The parameter "id" indicates the Pythia KF particle code, which
+// basically is the PDG particle identifier code.
+// In case the user has built a selection list via this procedure, only the
+// events in which one of the particles specified in the list was generated
+// will be kept.
+// The investigation of the generated particles takes place when the complete
+// event is in memory, including all (shortlived) mother particles and resonances.
+// So, the settings of the various particle decay modes have no influence on
+// the event selection described here.
+//
+// If no list has been specified, all events will be accepted.
+//
+// Note : id=0 will delete the selection list.
+//
+// Be aware of the fact that severe selection criteria (i.e. selecting only
+// rare events) may result in long runtimes before an event sample has been
+// obtained.
+//
+ if (!id)
+ {
+ if (fSelections)
+ {
+ delete fSelections;
+ fSelections=0;
+ }
+ }
+ else
+ {
+ Int_t kc=Pycomp(id);
+ if (!fSelections)
+ {
+ fSelections=new TArrayI(1);
+ fSelections->AddAt(kc,0);
+ }
+ else
+ {
+ Int_t exist=0;
+ Int_t size=fSelections->GetSize();
+ for (Int_t i=0; i<size; i++)
+ {
+ if (kc==fSelections->At(i))
+ {
+ exist=1;
+ break;
+ }
+ }
+
+ if (!exist)
+ {
+ fSelections->Set(size+1);
+ fSelections->AddAt(kc,size);
+ }
+ }
+ }
+}
+///////////////////////////////////////////////////////////////////////////
+Int_t AliCollider::GetSelectionFlag()
+{
+// Return the value of the selection flag for the total event.
+// When the event passed the selection criteria as specified via
+// SelectEvent() the value 1 is returned, otherwise the value 0 is returned.
+ return fSelect;
+}
+///////////////////////////////////////////////////////////////////////////
+Int_t AliCollider::IsSelected()
+{
+// Check whether the generated (sub)event contains one of the particles
+// specified in the selection list via SelectEvent().
+// If this is the case or when no selection list is present, the value 1
+// will be returned, indicating the event is selected to be kept.
+// Otherwise the value 0 will be returned.
+
+ if (!fSelections) return 1;
+
+ Int_t nsel=fSelections->GetSize();
+ Int_t npart=GetN();
+ Int_t kf,kc;
+
+ Int_t select=0;
+ for (Int_t jpart=1; jpart<=npart; jpart++)
+ {
+ kf=GetK(jpart,2);
+ kc=Pycomp(kf);
+ for (Int_t i=0; i<nsel; i++)
+ {
+ if (kc==fSelections->At(i))
+ {
+ select=1;
+ break;
+ }
+ }
+ if (select) break;
+ }
+ return select;
+}
+///////////////////////////////////////////////////////////////////////////
+void AliCollider::SetSpectatorPmin(Float_t pmin)
+{
+// Set minimal momentum in GeV/c for spectator tracks to be stored.
+// Spectator tracks with a momentum below this threshold will not be stored
+// in the (output) event structure.
+// This facility allows to minimise the output file size.
+// Note that when the user wants to boost the event into another reference
+// frame these spectator tracks might have got momenta above the threshold.
+// However, when the spectator tracks were not stored in the event structure
+// in the original frame, there is no way to retreive them anymore.
+ fSpecpmin=pmin;
+}
+///////////////////////////////////////////////////////////////////////////
+Float_t AliCollider::GetSpectatorPmin()
+{
+// Provide the minimal spectator momentum in GeV/c.
+ return fSpecpmin;
+}
+///////////////////////////////////////////////////////////////////////////
/* Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
* See cxx source for full Copyright notice */
-// $Id: AliCollider.h,v 1.5 2003/10/26 14:53:44 nick Exp $
+// $Id: AliCollider.h,v 1.6 2003/12/18 09:28:06 nick Exp $
#include "TPythia6.h"
#include "TString.h"
#include "TFile.h"
-#include "TTree.h"
+#include "TTree.h"
+#include "TArrayI.h"
#include "AliEvent.h"
#include "AliRandom.h"
void Init(char* frame,char* beam,char* target,Float_t win); // Standard Pythia initialisation
void Init(char* frame,Int_t zp,Int_t ap,Int_t zt,Int_t at,Float_t win); // Nucl-Nucl initialisation
void SetStable(Int_t id,Int_t mode=1); // Declare a certain particle as stable or not
+ void SelectEvent(Int_t id); // Select only events containing specified particles
+ Int_t GetSelectionFlag(); // Return the selection flag for this event
void MakeEvent(Int_t npt=0,Int_t mlist=-1,Int_t medit=1);// Generate a single event with npt participant nucleons
void EndRun(); // Properly close all buffers and output file
- AliEvent* GetEvent(); // Provide pointer to the generated event structure
+ AliEvent* GetEvent(Int_t select=0); // Provide pointer to the generated event structure
+ void SetSpectatorPmin(Float_t pmin); // Set minimal momentum for spectator track to be stored
+ Float_t GetSpectatorPmin(); // Provide the minimal momentum for spectator tracks
protected:
Int_t fVertexmode; // The vertex structure creation mode
Float_t fFracnn; // Fraction of n+n collisions
AliRandom fRan; // Random number generator
AliEvent* fEvent; // The produced event structure
+ Float_t fSpecpmin; // The minimal momentum for spectator tracks to be stored
TFile* fOutFile; // The user defined output data file
TTree* fOutTree; // The standard ROOT output tree
+ TArrayI* fSelections; // The particle KC codes for event selection
+ Int_t fSelect; // Flag to indicate whether the total event is selected (1) or not (0)
+
+ Int_t IsSelected(); // Check whether (sub)event passed the selection criteria
void GetFractions(Float_t zp,Float_t ap,Float_t zt,Float_t at); // Determine various N-N collision fractions
- ClassDef(AliCollider,5) // Pythia based universal physics event generator
+ ClassDef(AliCollider,6) // Pythia based universal physics event generator
};
#endif
git://git.uio.no / u / mrichter / AliRoot.git / commitdiff