-/**************************************************************************
+ /**************************************************************************
* Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
* *
* Author: The ALICE Off-line Project. *
* provided "as is" without express or implied warranty. *
**************************************************************************/
+/* $Id$ */
+
//_________________________________________________________________________
-// Manager class for PHOS version for fast simulations
-//*-- Author : Y. Schutz SUBATECH
-//////////////////////////////////////////////////////////////////////////////
+// Implementation of the PHOS manager class for fast simulations
+// Tracks particles until the reach a grossly designed PHOS module
+// Modify the particles property (momentum, energy, type) according to
+// the PHOS response function. The result is called a virtual reconstructed
+// particle.
+//
+//*-- Author: Yves Schutz (SUBATECH)
// --- ROOT system ---
-
-#include "TBRIK.h"
-#include "TNode.h"
-#include "TParticle.h"
+
+#include <TBRIK.h>
+#include <TGeometry.h>
+#include <TNode.h>
+#include <TParticle.h>
+#include "TClonesArray.h"
+#include <TVirtualMC.h>
// --- Standard library ---
-#include <cstdio>
-#include <cassert>
-
// --- AliRoot header files ---
-
+#include "AliPHOSFastRecParticle.h"
+#include "AliPHOSGeometry.h"
+#include "AliPHOSLoader.h"
#include "AliPHOSvFast.h"
#include "AliRun.h"
-#include "AliConst.h"
ClassImp(AliPHOSvFast)
//____________________________________________________________________________
-AliPHOSvFast::AliPHOSvFast()
+AliPHOSvFast::AliPHOSvFast() : AliPHOS()
{
- fFastRecParticles = 0 ;
- fNRecParticles = 0 ;
+ // default ctor : initialize data member
+ fBigBoxX = 0. ;
+ fBigBoxY = 0. ;
+ fBigBoxZ = 0. ;
+ fFastRecParticles = 0 ;
+ fNRecParticles = 0 ;
+ fRan = 0 ;
+ fResPara1 = 0. ;
+ fResPara2 = 0. ;
+ fResPara3 = 0. ;
+ fPosParaA0 = 0. ;
+ fPosParaA1 = 0. ;
+ fPosParaB0 = 0. ;
+ fPosParaB1 = 0. ;
+ fPosParaB2 = 0. ;
+
}
//____________________________________________________________________________
AliPHOSvFast::AliPHOSvFast(const char *name, const char *title):
AliPHOS(name,title)
{
- // gets an instance of the geometry parameters class
-
- fGeom = AliPHOSGeometry::GetInstance(title, "") ;
+ // ctor
- if (fGeom->IsInitialized() )
- cout << "AliPHOSvFast : PHOS geometry intialized for " << fGeom->GetName() << endl ;
- else
- cout << "AliPHOSvFast : PHOS geometry initialization failed !" << endl ;
- SetBigBox(0, fGeom->GetOuterBoxSize(0) ) ;
- SetBigBox(1, fGeom->GetOuterBoxSize(1) + fGeom->GetPPSDBoxSize(1) ) ;
- SetBigBox(2, fGeom->GetOuterBoxSize(0) );
-
+ // create the Loader
+
+ SetBigBox(0, GetGeometry()->GetOuterBoxSize(0) ) ;
+ SetBigBox(1, GetGeometry()->GetOuterBoxSize(3) + GetGeometry()->GetCPVBoxSize(1) ) ;
+ SetBigBox(2, GetGeometry()->GetOuterBoxSize(2) );
+
fNRecParticles = 0 ;
- fFastRecParticles = new FastRecParticlesList("AliPHOSFastRecParticle", 100) ;
-
- fResPara1 = 30.0 ;
- fResPara2 = 0.03 ;
- fResPara3 = 0.01 ;
-
+ fFastRecParticles = new AliPHOSFastRecParticle::FastRecParticlesList("AliPHOSFastRecParticle", 100) ;
+
+ fResPara1 = 0.030 ; // GeV
+ fResPara2 = 0.00003 ;
+ fResPara3 = 0.00001 ;
+
+ fPosParaA0 = 2.87 ; // mm
+ fPosParaA1 = -0.0975 ;
+ fPosParaB0 = 0.257 ;
+ fPosParaB1 = 0.137 ;
+ fPosParaB2 = 0.00619 ;
}
//____________________________________________________________________________
AliPHOSvFast::~AliPHOSvFast()
{
+ // dtor
fFastRecParticles->Delete() ;
delete fFastRecParticles ;
}
+//____________________________________________________________________________
+void AliPHOSvFast::Copy(AliPHOSvFast & fast)
+{
+ TObject::Copy(fast) ;
+ AliPHOS::Copy(fast) ;
+ fast.fBigBoxX = fBigBoxX ;
+ fast.fBigBoxY = fBigBoxY ;
+ fast.fBigBoxZ = fBigBoxZ ;
+ fast.fNRecParticles = fNRecParticles ;
+ fast.fRan = fRan ;
+ fast.fResPara1 = fResPara1 ;
+ fast.fResPara2 = fResPara2 ;
+ fast.fResPara3 = fResPara3 ;
+ fast.fPosParaA0 = fPosParaA0 ;
+ fast.fPosParaA1 = fPosParaA1 ;
+ fast.fPosParaB0 = fPosParaB0 ;
+ fast.fPosParaB1 = fPosParaB1 ;
+ fast.fFastRecParticles = new TClonesArray(fFastRecParticles->GetClass()->GetName(), 100) ;
+ Int_t index ;
+ for (index = 0 ; index < fFastRecParticles->GetEntries(); index++)
+ (fast.fFastRecParticles)->AddAt(fFastRecParticles->At(index), index) ;
+}
+
//____________________________________________________________________________
void AliPHOSvFast::AddRecParticle(const AliPHOSFastRecParticle & rp)
{
- new( (*fFastRecParticles)[fNRecParticles] ) AliPHOSFastRecParticle(rp) ;
- fNRecParticles++ ;
+ // Add a virtually reconstructed particle to the list
+
+ new( (*fFastRecParticles)[fNRecParticles] ) AliPHOSFastRecParticle(rp) ;
+ fNRecParticles++ ;
}
//____________________________________________________________________________
void AliPHOSvFast::BuildGeometry()
{
-
// Build the PHOS geometry for the ROOT display
-
+ //BEGIN_HTML
+ /*
+ <H2>
+ PHOS FAST in ALICE displayed by root
+ </H2>
+ <H4> All Views </H4>
+ <P>
+ <CENTER>
+ <IMG Align=BOTTOM ALT="Fast All Views" SRC="../images/AliPHOSvFastAllViews.gif">
+ </CENTER></P>
+ <H4> Front View </H4>
+ <P>
+ <CENTER>
+ <IMG Align=BOTTOM ALT="Fast Front View" SRC="../images/AliPHOSvFastFrontView.gif">
+ </CENTER></P>
+ */
+ //END_HTML
+
const Int_t kColorPHOS = kRed ;
- Double_t const kRADDEG = 180.0 / kPI ;
+ Double_t const kRADDEG = 180.0 / TMath::Pi() ;
new TBRIK( "BigBox", "PHOS box", "void", GetBigBox(0)/2,
GetBigBox(1)/2,
// position PHOS into ALICE
- Float_t r = fGeom->GetIPtoOuterCoverDistance() + GetBigBox(1) / 2.0 ;
+ Float_t r = GetGeometry()->GetIPtoCrystalSurface() + GetBigBox(1) / 2.0 ;
Int_t number = 988 ;
- Float_t pphi = TMath::ATan( GetBigBox(0) / ( 2.0 * fGeom->GetIPtoOuterCoverDistance() ) ) ;
+ Float_t pphi = TMath::ATan( GetBigBox(0) / ( 2.0 * GetGeometry()->GetIPtoCrystalSurface() ) ) ;
pphi *= kRADDEG ;
TNode * top = gAlice->GetGeometry()->GetNode("alice") ;
char * nodename = new char[20] ;
char * rotname = new char[20] ;
- for( Int_t i = 1; i <= fGeom->GetNModules(); i++ ) {
- Float_t angle = pphi * 2 * ( i - fGeom->GetNModules() / 2.0 - 0.5 ) ;
+ for( Int_t i = 1; i <= GetGeometry()->GetNModules(); i++ ) {
+ Float_t angle = pphi * 2 * ( i - GetGeometry()->GetNModules() / 2.0 - 0.5 ) ;
sprintf(rotname, "%s%d", "rot", number++) ;
new TRotMatrix(rotname, rotname, 90, angle, 90, 90 + angle, 0, 0);
top->cd();
//____________________________________________________________________________
void AliPHOSvFast::CreateGeometry()
{
-
+ // Create the geometry for GEANT
+
AliPHOSvFast *phostmp = (AliPHOSvFast*)gAlice->GetModule("PHOS") ;
-
+
if ( phostmp == NULL ) {
fprintf(stderr, "PHOS detector not found!\n") ;
// --- Position PHOS mdules in ALICE setup ---
Int_t idrotm[99] ;
- Double_t const kRADDEG = 180.0 / kPI ;
+ Double_t const kRADDEG = 180.0 / TMath::Pi() ;
- for( Int_t i = 1; i <= fGeom->GetNModules(); i++ ) {
+ for( Int_t i = 1; i <= GetGeometry()->GetNModules(); i++ ) {
- Float_t angle = fGeom->GetPHOSAngle(i) ;
+ Float_t angle = GetGeometry()->GetPHOSAngle(i) ;
AliMatrix(idrotm[i-1], 90.0, angle, 90.0, 90.0+angle, 0.0, 0.0) ;
- Float_t r = fGeom->GetIPtoOuterCoverDistance() + GetBigBox(1) / 2.0 ;
+ Float_t r = GetGeometry()->GetIPtoCrystalSurface() + GetBigBox(1) / 2.0 ;
Float_t xP1 = r * TMath::Sin( angle / kRADDEG ) ;
Float_t yP1 = -r * TMath::Cos( angle / kRADDEG ) ;
-
gMC->Gspos("PHOS", i, "ALIC", xP1, yP1, 0.0, idrotm[i-1], "ONLY") ;
} // for GetNModules
//____________________________________________________________________________
void AliPHOSvFast::Init(void)
{
-
+ // Prints out an information message
+
Int_t i;
printf("\n");
}
//___________________________________________________________________________
-Float_t AliPHOSvFast::GetBigBox(Int_t index)
+Float_t AliPHOSvFast::GetBigBox(Int_t index) const
{
+ // Get the X, Y or Z dimension of the box describing a PHOS module
+
Float_t rv = 0 ;
switch (index) {
}
return rv ;
}
-
//___________________________________________________________________________
+
void AliPHOSvFast::MakeBranch(Option_t* opt)
{
- //
- // Create a new branch in the current Root Tree
- // The branch of fHits is automatically split
- //
- AliDetector::MakeBranch(opt) ;
-
- char branchname[10];
- sprintf(branchname,"%s",GetName());
- char *cd = strstr(opt,"R");
-
- if (fFastRecParticles && gAlice->TreeR() && cd) {
- gAlice->TreeR()->Branch(branchname, &fFastRecParticles, fBufferSize);
+ // Create new branch in the current reconstructed Root Tree
+ AliDetector::MakeBranch(opt);
+ const char *cd = strstr(opt,"R");
+
+ if (fFastRecParticles && fLoader->TreeR() && cd) {
+ MakeBranchInTree(fLoader->TreeR(), GetName(), &fFastRecParticles, fBufferSize, 0);
}
}
-
//____________________________________________________________________________
-Double_t AliPHOSvFast::MakeEnergy(const Double_t energy)
+
+Double_t AliPHOSvFast::MakeEnergy(Double_t energy)
{
- Double_t sigma = SigmaE(energy*1000.) ;
- return fRan.Gaus(energy*1000., sigma)/1000. ;
-}
+ // Smears the energy according to the energy dependent energy resolution.
+ // A gaussian distribution is assumed
+ Double_t sigma = SigmaE(energy) ;
+ return fRan.Gaus(energy, sigma) ;
+}
//____________________________________________________________________________
-void AliPHOSvFast::MakeRecParticle(AliPHOSFastRecParticle & rp)
+
+TVector3 AliPHOSvFast::MakePosition(Double_t energy, TVector3 pos, Double_t theta, Double_t phi)
{
+ // Smears the impact position according to the energy dependent position resolution
+ // A gaussian position distribution is assumed
+
+ TVector3 newpos ;
+ Double_t sigma = SigmaP( energy, theta*180./TMath::Pi() ) ;
+ Double_t x = fRan.Gaus( pos.X(), sigma ) ;
+ sigma = SigmaP( energy, phi*180./TMath::Pi() ) ;
+ Double_t z = fRan.Gaus( pos.Z(), sigma ) ;
+ Double_t y = pos.Y() ;
+
+ newpos.SetX(x) ;
+ newpos.SetY(y) ;
+ newpos.SetZ(z) ;
+
+ return newpos ;
+}
- // get the detected type of particle
- Int_t type = MakeType( rp.GetName() ) ;
+//____________________________________________________________________________
+void AliPHOSvFast::MakeRecParticle(Int_t modid, TVector3 pos, AliPHOSFastRecParticle & rp)
+{
+ // Modify the primary particle properties according
+ // 1. the response function of PHOS
+ // 2. the performance of the EMC+PPSD setup
+
+ Int_t type = MakeType( rp ) ;
rp.SetType(type) ;
rp.Momentum(momentum) ;
Double_t kineticenergy = TMath::Sqrt( TMath::Power(momentum.E(), 2) - TMath::Power(rp.GetMass(), 2) ) ;
Double_t modifiedkineticenergy = MakeEnergy(kineticenergy ) ;
- cout << modifiedkineticenergy << endl ;
- // rp.SetMomentum(tempo) ;
+ Double_t modifiedenergy = TMath::Sqrt( TMath::Power(modifiedkineticenergy, 2)
+ + TMath::Power( rp.GetMass(), 2) ) ;
+
+ // get the angle of incidence
+
+ Double_t incidencetheta = 90. * TMath::Pi() /180 - rp.Theta() ;
+ Double_t incidencephi = ( 270 + GetGeometry()->GetPHOSAngle(modid) ) * TMath::Pi() / 180. - rp.Phi() ;
+
+ // get the detected direction
+
+ TVector3 modifiedposition = MakePosition(kineticenergy, pos, incidencetheta, incidencephi) ;
+ modifiedposition *= modifiedkineticenergy / modifiedposition.Mag() ;
+
+ // Set the modified 4-momentum of the reconstructed particle
+
+ rp.SetMomentum(modifiedposition.X(), modifiedposition.Y(), modifiedposition.Z(), modifiedenergy) ;
+
}
//____________________________________________________________________________
-Int_t AliPHOSvFast::MakeType(const Text_t * name)
+Int_t AliPHOSvFast::MakeType(AliPHOSFastRecParticle & rp )
{
- Int_t rv = kUNDEFINED ;
+ // Generate a particle type using the performance of the EMC+PPSD setup
+
+ Int_t rv = AliPHOSFastRecParticle::kUNDEFINED ;
+ Int_t charge = (Int_t)rp.GetPDG()->Charge() ;
+ Int_t test ;
+ Float_t ran ;
+ if ( charge != 0 && ( TMath::Abs(rp.GetPdgCode()) != 11 ) )
+ test = - 1 ;
+ else
+ test = rp.GetPdgCode() ;
+
+ Fatal("MakeType", "SHOULD NOT BE USED until values of probabilities are properly set ") ;
+ // NB: ALL VALUES SHOULD BE CHECKED !!!!
+ switch (test) {
+
+ case 22: // it's a photon // NB: ALL VALUES SHOLD BE CHECKED !!!!
+ ran = fRan.Rndm() ;
+ if( ran <= 0.9498 )
+ rv = AliPHOSFastRecParticle::kNEUTRALHAFAST ;
+ else
+ rv = AliPHOSFastRecParticle::kNEUTRALEMFAST ;
+ break ;
+
+ case 2112: // it's a neutron
+ ran = fRan.Rndm() ;
+ if ( ran <= 0.9998 )
+ rv = AliPHOSFastRecParticle::kNEUTRALHASLOW ;
+ else
+ rv = AliPHOSFastRecParticle::kNEUTRALEMSLOW ;
+ break ;
+
+ case -2112: // it's a anti-neutron
+ ran = fRan.Rndm() ;
+ if ( ran <= 0.9984 )
+ rv = AliPHOSFastRecParticle::kNEUTRALHASLOW ;
+ else
+ rv = AliPHOSFastRecParticle::kNEUTRALEMSLOW ;
+ break ;
+
+ case 11: // it's a electron
+ ran = fRan.Rndm() ;
+ if ( ran <= 0.9996 )
+ rv = AliPHOSFastRecParticle::kCHARGEDEMFAST ;
+ else
+ rv = AliPHOSFastRecParticle::kCHARGEDHAFAST ;
+ break;
+
+ case -11: // it's a positon
+ ran = fRan.Rndm() ;
+ if ( ran <= 0.9996 )
+ rv = AliPHOSFastRecParticle::kCHARGEDEMFAST ;
+ else
+ rv = AliPHOSFastRecParticle::kCHARGEDHAFAST ;
+ break;
+
+ case -1: // it's a charged
+ ran = fRan.Rndm() ;
+ if ( ran <= 0.9996 )
+ rv = AliPHOSFastRecParticle::kCHARGEDHAFAST ;
+ else
+ rv = AliPHOSFastRecParticle::kNEUTRALHAFAST ;
+
+ break ;
+ }
+
+
return rv ;
}
//___________________________________________________________________________
-void AliPHOSvFast::SetBigBox(Int_t index, Float_t value)
+void AliPHOSvFast::ResetPoints()
+{
+ // This overloads the method in AliDetector
+
+ ResetFastRecParticles() ;
+}
+
+//___________________________________________________________________________
+void AliPHOSvFast::ResetFastRecParticles()
{
+ // Resets the list of virtual reconstructed particles
+
+ if (fFastRecParticles)
+ fFastRecParticles->Clear() ;
+ fNRecParticles = 0 ;
+}
+//___________________________________________________________________________
+void AliPHOSvFast::SetBigBox(Int_t index, Float_t value)
+{
+ // Set the size of the Box describing a PHOS module
+
switch (index) {
case 0:
fBigBoxX = value ;
//____________________________________________________________________________
Double_t AliPHOSvFast::SigmaE(Double_t energy)
{
+ // Calculates the energy dependent energy resolution
+
Double_t rv = -1 ;
rv = TMath::Sqrt( TMath::Power(fResPara1/energy, 2)
return rv * energy ;
}
+//____________________________________________________________________________
+Double_t AliPHOSvFast::SigmaP(Double_t energy, Double_t incidence)
+{
+ // Calculates the energy dependent position resolution
+
+ Double_t paraA = fPosParaA0 + fPosParaA1 * incidence ;
+ Double_t paraB = fPosParaB0 + fPosParaB1 * incidence + fPosParaB2 * incidence * incidence ;
+
+ return ( paraA / TMath::Sqrt(energy) + paraB ) * 0.1 ; // in cm
+}
+
//____________________________________________________________________________
void AliPHOSvFast::StepManager(void)
{
+ // Only verifies if the particle reaches PHOS and stops the tracking
- Int_t primary = gAlice->GetPrimary( gAlice->CurrentTrack() );
TLorentzVector lv ;
gMC->TrackPosition(lv) ;
+ TVector3 pos = lv.Vect() ;
+ Int_t modid ;
+ gMC->CurrentVolID(modid);
- // Makes a reconstructed particle from the primary particle
+ Float_t energy = gMC->Etot() ; //Total energy of current track
+
+ //Calculating mass of current particle
+ TDatabasePDG * pdg = TDatabasePDG::Instance() ;
+ TParticlePDG * partPDG = pdg->GetParticle(gMC->TrackPid()) ;
+ Float_t mass = partPDG->Mass() ;
- TClonesArray * particlelist = gAlice->Particles() ;
- TParticle * part = (TParticle *)particlelist->At(primary) ;
+ if(energy > mass){
+ pos.SetMag(TMath::Sqrt(energy*energy-mass*mass)) ;
+ TLorentzVector pTrack(pos, energy) ;
- AliPHOSFastRecParticle rp(*part) ;
+ TParticle * part = new TParticle(gMC->TrackPid(), 0,-1,-1,-1,-1, pTrack, lv) ;
+
+ AliPHOSFastRecParticle rp(*part) ;
- // Adds the response of PHOS to the particle
- MakeRecParticle(rp) ;
+ // Adds the response of PHOS to the particle
+ MakeRecParticle(modid, pos, rp) ;
+
+ // add the `track' particle to the FastRecParticles list
- // add the primary particle to the FastRecParticles list
- AddRecParticle(rp) ;
+ AddRecParticle(rp) ;
+ part->Delete() ;
+ }
// stop the track as soon PHOS is reached
+
gMC->StopTrack() ;
}