[u/mrichter/AliRoot.git] / PHOS / AliPHOSvFast.cxx

  /**************************************************************************
 * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
 *                                                                        *
 * Author: The ALICE Off-line Project.                                    *
 * Contributors are mentioned in the code where appropriate.              *
 *                                                                        *
 * Permission to use, copy, modify and distribute this software and its   *
 * documentation strictly for non-commercial purposes is hereby granted   *
 * without fee, provided that the above copyright notice appears in all   *
 * copies and that both the copyright notice and this permission notice   *
 * appear in the supporting documentation. The authors make no claims     *
 * about the suitability of this software for any purpose. It is          *
 * provided "as is" without express or implied warranty.                  *
 **************************************************************************/

/* $Id$ */

/* History of cvs commits:
 *
 * $Log$
 * Revision 1.30  2006/09/13 07:31:01  kharlov
 * Effective C++ corrections (T.Pocheptsov)
 *
 * Revision 1.29  2005/05/28 14:19:05  schutz
 * Compilation warnings fixed by T.P.
 *
 */

//_________________________________________________________________________
// 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 <TGeometry.h>
#include <TNode.h>
#include <TParticle.h>
#include "TClonesArray.h" 
#include <TVirtualMC.h>

// --- Standard library ---

// --- AliRoot header files ---
#include "AliPHOSFastRecParticle.h"
#include "AliPHOSGeometry.h"
#include "AliPHOSLoader.h"
#include "AliPHOSvFast.h"
#include "AliRun.h"

ClassImp(AliPHOSvFast)

AliPHOSvFast::AliPHOSvFast() :
  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.)    
{
  // default ctor : initialize data member
}

//____________________________________________________________________________
AliPHOSvFast::AliPHOSvFast(const char *name, const char *title):
  AliPHOS(name,title),
  fBigBoxX(0.),
  fBigBoxY(0.),
  fBigBoxZ(0.),
  fFastRecParticles(new AliPHOSFastRecParticle::FastRecParticlesList("AliPHOSFastRecParticle", 100)),
  fNRecParticles(0),
  fRan(0),
  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)
{
  // ctor
  // create the Loader 
  SetBigBox(0, GetGeometry()->GetOuterBoxSize(0) ) ;
  SetBigBox(1, GetGeometry()->GetOuterBoxSize(3) + GetGeometry()->GetCPVBoxSize(1) ) ; 
  SetBigBox(2, GetGeometry()->GetOuterBoxSize(2) ); 
}

//____________________________________________________________________________
AliPHOSvFast::~AliPHOSvFast()
{
  // dtor
 
  fFastRecParticles->Delete() ; 
  delete fFastRecParticles ;
  fFastRecParticles = 0 ; 

}

//____________________________________________________________________________
void AliPHOSvFast::AddRecParticle(const AliPHOSFastRecParticle & rp)
{  
  // 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 / TMath::Pi() ;
  
  new TBRIK( "BigBox", "PHOS box", "void", GetBigBox(0)/2, 
	     GetBigBox(1)/2, 
	     GetBigBox(2)/2 );
  
  // position PHOS into ALICE

  Float_t r = GetGeometry()->GetIPtoCrystalSurface() + GetBigBox(1) / 2.0 ;
  Int_t number = 988 ; 
  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 <= 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();
   sprintf(nodename,"%s%d", "Module", i) ;    
   Float_t x =  r * TMath::Sin( angle / kRADDEG ) ;
   Float_t y = -r * TMath::Cos( angle / kRADDEG ) ;
   TNode * bigboxnode = new TNode(nodename, nodename, "BigBox", x, y, 0, rotname ) ;
   bigboxnode->SetLineColor(kColorPHOS) ;
   fNodes->Add(bigboxnode) ;
  }
  delete[] nodename ; 
  delete[] rotname ; 
}

//____________________________________________________________________________
void AliPHOSvFast::CreateGeometry()
{
  // Create the geometry for GEANT
  
  AliPHOSvFast *phostmp = (AliPHOSvFast*)gAlice->GetModule("PHOS") ;
  
  if ( phostmp == NULL ) {
    
    fprintf(stderr, "PHOS detector not found!\n") ;
    return ;
    
  }

  // Get pointer to the array containing media indeces
  Int_t *idtmed = fIdtmed->GetArray() - 699 ;
  
  Float_t bigbox[3] ; 
  bigbox[0] =   GetBigBox(0) / 2.0 ;
  bigbox[1] =   GetBigBox(1) / 2.0 ;
  bigbox[2] =   GetBigBox(2) / 2.0 ;
  
  gMC->Gsvolu("PHOS", "BOX ", idtmed[798], bigbox, 3) ;
  
  // --- Position  PHOS mdules in ALICE setup ---
  
  Int_t idrotm[99] ;
  Double_t const kRADDEG = 180.0 / TMath::Pi() ;
  
  for( Int_t i = 1; i <= GetGeometry()->GetNModules(); 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 = 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");
  for(i=0;i<35;i++) printf("*");
  printf(" FAST PHOS_INIT ");
  for(i=0;i<35;i++) printf("*");
  printf("\n");

  // Here the PHOS initialisation code (if any!)

  for(i=0;i<80;i++) printf("*");
  printf("\n");
  
}

//___________________________________________________________________________
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) {
  case 0:
    rv = fBigBoxX ; 
    break ; 
  case 1:
     rv = fBigBoxY ; 
    break ; 
  case 2:
     rv = fBigBoxZ ; 
    break ; 
 }
  return rv ; 
}
//___________________________________________________________________________

void AliPHOSvFast::MakeBranch(Option_t* opt)
{  
  // 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(Double_t energy)
{  
  // 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) ;   
}
//____________________________________________________________________________

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 ; 
}

//____________________________________________________________________________
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) ;

  
  // get the detected energy

  TLorentzVector momentum ;  
  rp.Momentum(momentum) ; 
  Double_t kineticenergy = TMath::Sqrt( TMath::Power(momentum.E(), 2) - TMath::Power(rp.GetMass(), 2) ) ; 
  Double_t modifiedkineticenergy = MakeEnergy(kineticenergy ) ;
  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(AliPHOSFastRecParticle & rp )
{
  // 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::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 ; 
    break ; 
  case 1:
    fBigBoxY = value ; 
    break ; 
  case 2:
    fBigBoxZ = value ; 
    break ; 
 }

}

//____________________________________________________________________________
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) 
	       + TMath::Power(fResPara2/TMath::Sqrt(energy), 2) 
	       + TMath::Power(fResPara3, 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 

  TLorentzVector lv ; 
  gMC->TrackPosition(lv) ;
  TVector3 pos = lv.Vect() ; 
  Int_t modid  ; 
  gMC->CurrentVolID(modid);
  
  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() ;

  if(energy > mass){
    pos.SetMag(TMath::Sqrt(energy*energy-mass*mass)) ;
    TLorentzVector pTrack(pos, energy) ;  

    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(modid, pos, rp) ;
    
    // add the `track' particle to the FastRecParticles list
  
    AddRecParticle(rp) ;

    part->Delete() ;
  }
  // stop the track as soon PHOS is reached
  
  gMC->StopTrack() ; 

}
Commit	Line	Data
88cb7938	1	/**************************************************************************
3decf5cb	2	* Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
	3	* *
	4	* Author: The ALICE Off-line Project. *
	5	* Contributors are mentioned in the code where appropriate. *
	6	* *
	7	* Permission to use, copy, modify and distribute this software and its *
	8	* documentation strictly for non-commercial purposes is hereby granted *
	9	* without fee, provided that the above copyright notice appears in all *
	10	* copies and that both the copyright notice and this permission notice *
	11	* appear in the supporting documentation. The authors make no claims *
	12	* about the suitability of this software for any purpose. It is *
	13	* provided "as is" without express or implied warranty. *
	14	**************************************************************************/
	15
b2a60966	16	/* $Id$ */
b2a60966	17
702ab87e	18	/* History of cvs commits:
	19	*
	20	* $Log$
e939a978	21	* Revision 1.30 2006/09/13 07:31:01 kharlov
	22	* Effective C++ corrections (T.Pocheptsov)
	23	*
43fbaae1	24	* Revision 1.29 2005/05/28 14:19:05 schutz
	25	* Compilation warnings fixed by T.P.
	26	*
702ab87e	27	*/
702ab87e	28
3decf5cb	29	//_________________________________________________________________________
b2a60966	30	// Implementation of the PHOS manager class for fast simulations
	31	// Tracks particles until the reach a grossly designed PHOS module
	32	// Modify the particles property (momentum, energy, type) according to
	33	// the PHOS response function. The result is called a virtual reconstructed
	34	// particle.
	35	//
	36	//*-- Author: Yves Schutz (SUBATECH)
3decf5cb	37
3decf5cb	38	// --- ROOT system ---
3a4295ee	39
88cb7938	40	#include <TBRIK.h>
88cb7938	41	#include <TGeometry.h>
	42	#include <TNode.h>
	43	#include <TParticle.h>
e957fea8	44	#include "TClonesArray.h"
88cb7938	45	#include <TVirtualMC.h>
3decf5cb	46
	47	// --- Standard library ---
	48
3decf5cb	49	// --- AliRoot header files ---
3a4295ee	50	#include "AliPHOSFastRecParticle.h"
88cb7938	51	#include "AliPHOSGeometry.h"
88cb7938	52	#include "AliPHOSLoader.h"
3decf5cb	53	#include "AliPHOSvFast.h"
3decf5cb	54	#include "AliRun.h"
3decf5cb	55
	56	ClassImp(AliPHOSvFast)
	57
43fbaae1	58	AliPHOSvFast::AliPHOSvFast() :
	59	fBigBoxX(0.),
	60	fBigBoxY(0.),
	61	fBigBoxZ(0.),
	62	fFastRecParticles(0),
	63	fNRecParticles(0),
	64	fRan(0),
	65	fResPara1(0.),
	66	fResPara2(0.),
	67	fResPara3(0.),
	68	fPosParaA0(0.),
	69	fPosParaA1(0.),
	70	fPosParaB0(0.),
	71	fPosParaB1(0.),
	72	fPosParaB2(0.)
3decf5cb	73	{
3a4295ee	74	// default ctor : initialize data member
3decf5cb	75	}
	76
	77	//____________________________________________________________________________
	78	AliPHOSvFast::AliPHOSvFast(const char name, const char title):
43fbaae1	79	AliPHOS(name,title),
	80	fBigBoxX(0.),
	81	fBigBoxY(0.),
	82	fBigBoxZ(0.),
	83	fFastRecParticles(new AliPHOSFastRecParticle::FastRecParticlesList("AliPHOSFastRecParticle", 100)),
	84	fNRecParticles(0),
	85	fRan(0),
	86	fResPara1(0.030), // GeV
	87	fResPara2(0.00003),
	88	fResPara3(0.00001),
	89	fPosParaA0(2.87), // mm
	90	fPosParaA1(-0.0975),
	91	fPosParaB0(0.257),
	92	fPosParaB1(0.137),
	93	fPosParaB2(0.00619)
3decf5cb	94	{
b2a60966	95	// ctor
88cb7938	96	// create the Loader
7a9d98f9	97	SetBigBox(0, GetGeometry()->GetOuterBoxSize(0) ) ;
	98	SetBigBox(1, GetGeometry()->GetOuterBoxSize(3) + GetGeometry()->GetCPVBoxSize(1) ) ;
	99	SetBigBox(2, GetGeometry()->GetOuterBoxSize(2) );
3decf5cb	100	}
	101
	102	//____________________________________________________________________________
	103	AliPHOSvFast::~AliPHOSvFast()
	104	{
b2a60966	105	// dtor
3decf5cb	106
a73f33f0	107	fFastRecParticles->Delete() ;
	108	delete fFastRecParticles ;
	109	fFastRecParticles = 0 ;
3decf5cb	110
	111	}
	112
	113	//____________________________________________________________________________
a73f33f0	114	void AliPHOSvFast::AddRecParticle(const AliPHOSFastRecParticle & rp)
a73f33f0	115	{
b2a60966	116	// Add a virtually reconstructed particle to the list
b2a60966	117
f96d3dc7	118	new( (*fFastRecParticles)[fNRecParticles] ) AliPHOSFastRecParticle(rp) ;
f96d3dc7	119	fNRecParticles++ ;
3decf5cb	120	}
	121
	122	//____________________________________________________________________________
	123	void AliPHOSvFast::BuildGeometry()
	124	{
3decf5cb	125	// Build the PHOS geometry for the ROOT display
b2a60966	126	//BEGIN_HTML
	127	/*
	128	<H2>
	129	PHOS FAST in ALICE displayed by root
	130	</H2>
	131	<H4> All Views </H4>
	132	<P>
	133	<CENTER>
	134	<IMG Align=BOTTOM ALT="Fast All Views" SRC="../images/AliPHOSvFastAllViews.gif">
	135	</CENTER></P>
	136	<H4> Front View </H4>
	137	<P>
	138	<CENTER>
	139	<IMG Align=BOTTOM ALT="Fast Front View" SRC="../images/AliPHOSvFastFrontView.gif">
	140	</CENTER></P>
	141	*/
	142	//END_HTML
	143
3decf5cb	144	const Int_t kColorPHOS = kRed ;
3decf5cb	145
a8c47ab6	146	Double_t const kRADDEG = 180.0 / TMath::Pi() ;
3decf5cb	147
	148	new TBRIK( "BigBox", "PHOS box", "void", GetBigBox(0)/2,
	149	GetBigBox(1)/2,
	150	GetBigBox(2)/2 );
	151
	152	// position PHOS into ALICE
	153
fa7cce36	154	Float_t r = GetGeometry()->GetIPtoCrystalSurface() + GetBigBox(1) / 2.0 ;
3decf5cb	155	Int_t number = 988 ;
fa7cce36	156	Float_t pphi = TMath::ATan( GetBigBox(0) / ( 2.0 * GetGeometry()->GetIPtoCrystalSurface() ) ) ;
3decf5cb	157	pphi *= kRADDEG ;
	158	TNode * top = gAlice->GetGeometry()->GetNode("alice") ;
	159
	160	char * nodename = new char[20] ;
	161	char * rotname = new char[20] ;
	162
fa7cce36	163	for( Int_t i = 1; i <= GetGeometry()->GetNModules(); i++ ) {
fa7cce36	164	Float_t angle = pphi * 2 * ( i - GetGeometry()->GetNModules() / 2.0 - 0.5 ) ;
3decf5cb	165	sprintf(rotname, "%s%d", "rot", number++) ;
	166	new TRotMatrix(rotname, rotname, 90, angle, 90, 90 + angle, 0, 0);
	167	top->cd();
	168	sprintf(nodename,"%s%d", "Module", i) ;
	169	Float_t x = r * TMath::Sin( angle / kRADDEG ) ;
	170	Float_t y = -r * TMath::Cos( angle / kRADDEG ) ;
	171	TNode * bigboxnode = new TNode(nodename, nodename, "BigBox", x, y, 0, rotname ) ;
	172	bigboxnode->SetLineColor(kColorPHOS) ;
	173	fNodes->Add(bigboxnode) ;
	174	}
	175	delete[] nodename ;
	176	delete[] rotname ;
	177	}
	178
	179	//____________________________________________________________________________
	180	void AliPHOSvFast::CreateGeometry()
	181	{
b2a60966	182	// Create the geometry for GEANT
b2a60966	183
3decf5cb	184	AliPHOSvFast phostmp = (AliPHOSvFast)gAlice->GetModule("PHOS") ;
b2a60966	185
3decf5cb	186	if ( phostmp == NULL ) {
	187
	188	fprintf(stderr, "PHOS detector not found!\n") ;
	189	return ;
	190
	191	}
	192
	193	// Get pointer to the array containing media indeces
	194	Int_t *idtmed = fIdtmed->GetArray() - 699 ;
	195
	196	Float_t bigbox[3] ;
	197	bigbox[0] = GetBigBox(0) / 2.0 ;
	198	bigbox[1] = GetBigBox(1) / 2.0 ;
	199	bigbox[2] = GetBigBox(2) / 2.0 ;
	200
	201	gMC->Gsvolu("PHOS", "BOX ", idtmed[798], bigbox, 3) ;
	202
	203	// --- Position PHOS mdules in ALICE setup ---
	204
	205	Int_t idrotm[99] ;
a8c47ab6	206	Double_t const kRADDEG = 180.0 / TMath::Pi() ;
3decf5cb	207
fa7cce36	208	for( Int_t i = 1; i <= GetGeometry()->GetNModules(); i++ ) {
3decf5cb	209
fa7cce36	210	Float_t angle = GetGeometry()->GetPHOSAngle(i) ;
3decf5cb	211	AliMatrix(idrotm[i-1], 90.0, angle, 90.0, 90.0+angle, 0.0, 0.0) ;
3decf5cb	212
fa7cce36	213	Float_t r = GetGeometry()->GetIPtoCrystalSurface() + GetBigBox(1) / 2.0 ;
3decf5cb	214
	215	Float_t xP1 = r * TMath::Sin( angle / kRADDEG ) ;
	216	Float_t yP1 = -r * TMath::Cos( angle / kRADDEG ) ;
3decf5cb	217	gMC->Gspos("PHOS", i, "ALIC", xP1, yP1, 0.0, idrotm[i-1], "ONLY") ;
	218
	219	} // for GetNModules
	220
	221	}
	222
	223
	224	//____________________________________________________________________________
	225	void AliPHOSvFast::Init(void)
	226	{
b2a60966	227	// Prints out an information message
b2a60966	228
3decf5cb	229	Int_t i;
	230
	231	printf("\n");
	232	for(i=0;i<35;i++) printf("*");
	233	printf(" FAST PHOS_INIT ");
	234	for(i=0;i<35;i++) printf("*");
	235	printf("\n");
	236
	237	// Here the PHOS initialisation code (if any!)
	238
	239	for(i=0;i<80;i++) printf("*");
	240	printf("\n");
	241
	242	}
	243
	244	//___________________________________________________________________________
3a4295ee	245	Float_t AliPHOSvFast::GetBigBox(Int_t index) const
3decf5cb	246	{
b2a60966	247	// Get the X, Y or Z dimension of the box describing a PHOS module
b2a60966	248
3decf5cb	249	Float_t rv = 0 ;
	250
	251	switch (index) {
	252	case 0:
	253	rv = fBigBoxX ;
	254	break ;
	255	case 1:
	256	rv = fBigBoxY ;
	257	break ;
	258	case 2:
	259	rv = fBigBoxZ ;
	260	break ;
	261	}
	262	return rv ;
	263	}
3decf5cb	264	//___________________________________________________________________________
88cb7938	265
88cb7938	266	void AliPHOSvFast::MakeBranch(Option_t* opt)
3decf5cb	267	{
b2a60966	268	// Create new branch in the current reconstructed Root Tree
88cb7938	269	AliDetector::MakeBranch(opt);
3a4295ee	270	const char *cd = strstr(opt,"R");
3decf5cb	271
88cb7938	272	if (fFastRecParticles && fLoader->TreeR() && cd) {
88cb7938	273	MakeBranchInTree(fLoader->TreeR(), GetName(), &fFastRecParticles, fBufferSize, 0);
3decf5cb	274	}
3decf5cb	275	}
a73f33f0	276	//____________________________________________________________________________
88cb7938	277
fc7e2f43	278	Double_t AliPHOSvFast::MakeEnergy(Double_t energy)
a73f33f0	279	{
b2a60966	280	// Smears the energy according to the energy dependent energy resolution.
	281	// A gaussian distribution is assumed
	282
b1aa729d	283	Double_t sigma = SigmaE(energy) ;
b1aa729d	284	return fRan.Gaus(energy, sigma) ;
a73f33f0	285	}
a73f33f0	286	//____________________________________________________________________________
88cb7938	287
fc7e2f43	288	TVector3 AliPHOSvFast::MakePosition(Double_t energy, TVector3 pos, Double_t theta, Double_t phi)
a73f33f0	289	{
b2a60966	290	// Smears the impact position according to the energy dependent position resolution
	291	// A gaussian position distribution is assumed
	292
b1aa729d	293	TVector3 newpos ;
	294	Double_t sigma = SigmaP( energy, theta*180./TMath::Pi() ) ;
	295	Double_t x = fRan.Gaus( pos.X(), sigma ) ;
	296	sigma = SigmaP( energy, phi*180./TMath::Pi() ) ;
	297	Double_t z = fRan.Gaus( pos.Z(), sigma ) ;
	298	Double_t y = pos.Y() ;
	299
	300	newpos.SetX(x) ;
	301	newpos.SetY(y) ;
	302	newpos.SetZ(z) ;
	303
	304	return newpos ;
	305	}
a73f33f0	306
b1aa729d	307	//____________________________________________________________________________
fc7e2f43	308	void AliPHOSvFast::MakeRecParticle(Int_t modid, TVector3 pos, AliPHOSFastRecParticle & rp)
b1aa729d	309	{
b2a60966	310	// Modify the primary particle properties according
	311	// 1. the response function of PHOS
	312	// 2. the performance of the EMC+PPSD setup
	313
b1aa729d	314	Int_t type = MakeType( rp ) ;
a73f33f0	315	rp.SetType(type) ;
	316
	317
	318	// get the detected energy
	319
	320	TLorentzVector momentum ;
	321	rp.Momentum(momentum) ;
	322	Double_t kineticenergy = TMath::Sqrt( TMath::Power(momentum.E(), 2) - TMath::Power(rp.GetMass(), 2) ) ;
	323	Double_t modifiedkineticenergy = MakeEnergy(kineticenergy ) ;
b1aa729d	324	Double_t modifiedenergy = TMath::Sqrt( TMath::Power(modifiedkineticenergy, 2)
	325	+ TMath::Power( rp.GetMass(), 2) ) ;
	326
	327	// get the angle of incidence
	328
	329	Double_t incidencetheta = 90. * TMath::Pi() /180 - rp.Theta() ;
fa7cce36	330	Double_t incidencephi = ( 270 + GetGeometry()->GetPHOSAngle(modid) ) * TMath::Pi() / 180. - rp.Phi() ;
b1aa729d	331
	332	// get the detected direction
	333
	334	TVector3 modifiedposition = MakePosition(kineticenergy, pos, incidencetheta, incidencephi) ;
	335	modifiedposition *= modifiedkineticenergy / modifiedposition.Mag() ;
	336
	337	// Set the modified 4-momentum of the reconstructed particle
	338
	339	rp.SetMomentum(modifiedposition.X(), modifiedposition.Y(), modifiedposition.Z(), modifiedenergy) ;
	340
a73f33f0	341	}
	342
	343	//____________________________________________________________________________
b1aa729d	344	Int_t AliPHOSvFast::MakeType(AliPHOSFastRecParticle & rp )
a73f33f0	345	{
b2a60966	346	// Generate a particle type using the performance of the EMC+PPSD setup
b2a60966	347
9ec91567	348	Int_t rv = AliPHOSFastRecParticle::kUNDEFINED ;
b1aa729d	349	Int_t charge = (Int_t)rp.GetPDG()->Charge() ;
	350	Int_t test ;
	351	Float_t ran ;
f96d3dc7	352	if ( charge != 0 && ( TMath::Abs(rp.GetPdgCode()) != 11 ) )
b1aa729d	353	test = - 1 ;
	354	else
	355	test = rp.GetPdgCode() ;
	356
a4765fe4	357	Fatal("MakeType", "SHOULD NOT BE USED until values of probabilities are properly set ") ;
a4765fe4	358	// NB: ALL VALUES SHOULD BE CHECKED !!!!
b1aa729d	359	switch (test) {
b1aa729d	360
3a4295ee	361	case 22: // it's a photon // NB: ALL VALUES SHOLD BE CHECKED !!!!
b1aa729d	362	ran = fRan.Rndm() ;
3a4295ee	363	if( ran <= 0.9498 )
	364	rv = AliPHOSFastRecParticle::kNEUTRALHAFAST ;
	365	else
	366	rv = AliPHOSFastRecParticle::kNEUTRALEMFAST ;
b1aa729d	367	break ;
	368
	369	case 2112: // it's a neutron
	370	ran = fRan.Rndm() ;
	371	if ( ran <= 0.9998 )
3a4295ee	372	rv = AliPHOSFastRecParticle::kNEUTRALHASLOW ;
b1aa729d	373	else
3a4295ee	374	rv = AliPHOSFastRecParticle::kNEUTRALEMSLOW ;
b1aa729d	375	break ;
3a4295ee	376
b1aa729d	377	case -2112: // it's a anti-neutron
	378	ran = fRan.Rndm() ;
	379	if ( ran <= 0.9984 )
3a4295ee	380	rv = AliPHOSFastRecParticle::kNEUTRALHASLOW ;
b1aa729d	381	else
3a4295ee	382	rv = AliPHOSFastRecParticle::kNEUTRALEMSLOW ;
b1aa729d	383	break ;
	384
	385	case 11: // it's a electron
	386	ran = fRan.Rndm() ;
	387	if ( ran <= 0.9996 )
3a4295ee	388	rv = AliPHOSFastRecParticle::kCHARGEDEMFAST ;
b1aa729d	389	else
3a4295ee	390	rv = AliPHOSFastRecParticle::kCHARGEDHAFAST ;
b1aa729d	391	break;
b1aa729d	392
f96d3dc7	393	case -11: // it's a positon
b1aa729d	394	ran = fRan.Rndm() ;
b1aa729d	395	if ( ran <= 0.9996 )
3a4295ee	396	rv = AliPHOSFastRecParticle::kCHARGEDEMFAST ;
b1aa729d	397	else
3a4295ee	398	rv = AliPHOSFastRecParticle::kCHARGEDHAFAST ;
b1aa729d	399	break;
	400
	401	case -1: // it's a charged
	402	ran = fRan.Rndm() ;
	403	if ( ran <= 0.9996 )
3a4295ee	404	rv = AliPHOSFastRecParticle::kCHARGEDHAFAST ;
b1aa729d	405	else
3a4295ee	406	rv = AliPHOSFastRecParticle::kNEUTRALHAFAST ;
b1aa729d	407
	408	break ;
	409	}
	410
	411
a73f33f0	412	return rv ;
	413	}
	414
f96d3dc7	415	//___________________________________________________________________________
	416	void AliPHOSvFast::ResetPoints()
	417	{
b2a60966	418	// This overloads the method in AliDetector
b2a60966	419
f96d3dc7	420	ResetFastRecParticles() ;
	421	}
	422
	423	//___________________________________________________________________________
	424	void AliPHOSvFast::ResetFastRecParticles()
	425	{
b2a60966	426	// Resets the list of virtual reconstructed particles
b2a60966	427
f96d3dc7	428	if (fFastRecParticles)
	429	fFastRecParticles->Clear() ;
	430	fNRecParticles = 0 ;
	431	}
	432
3decf5cb	433	//___________________________________________________________________________
	434	void AliPHOSvFast::SetBigBox(Int_t index, Float_t value)
	435	{
b2a60966	436	// Set the size of the Box describing a PHOS module
b2a60966	437
3decf5cb	438	switch (index) {
	439	case 0:
	440	fBigBoxX = value ;
	441	break ;
	442	case 1:
	443	fBigBoxY = value ;
	444	break ;
	445	case 2:
	446	fBigBoxZ = value ;
	447	break ;
	448	}
	449
	450	}
	451
a73f33f0	452	//____________________________________________________________________________
	453	Double_t AliPHOSvFast::SigmaE(Double_t energy)
	454	{
b2a60966	455	// Calculates the energy dependent energy resolution
b2a60966	456
a73f33f0	457	Double_t rv = -1 ;
	458
	459	rv = TMath::Sqrt( TMath::Power(fResPara1/energy, 2)
	460	+ TMath::Power(fResPara2/TMath::Sqrt(energy), 2)
	461	+ TMath::Power(fResPara3, 2) ) ;
	462
	463	return rv * energy ;
	464	}
	465
b1aa729d	466	//____________________________________________________________________________
7a9d98f9	467	Double_t AliPHOSvFast::SigmaP(Double_t energy, Double_t incidence)
b1aa729d	468	{
b2a60966	469	// Calculates the energy dependent position resolution
b2a60966	470
b1aa729d	471	Double_t paraA = fPosParaA0 + fPosParaA1 * incidence ;
	472	Double_t paraB = fPosParaB0 + fPosParaB1 * incidence + fPosParaB2 * incidence * incidence ;
	473
	474	return ( paraA / TMath::Sqrt(energy) + paraB ) * 0.1 ; // in cm
	475	}
	476
3decf5cb	477	//____________________________________________________________________________
	478	void AliPHOSvFast::StepManager(void)
	479	{
b2a60966	480	// Only verifies if the particle reaches PHOS and stops the tracking
3a4295ee	481
a73f33f0	482	TLorentzVector lv ;
a73f33f0	483	gMC->TrackPosition(lv) ;
b1aa729d	484	TVector3 pos = lv.Vect() ;
	485	Int_t modid ;
	486	gMC->CurrentVolID(modid);
a73f33f0	487
3a4295ee	488	Float_t energy = gMC->Etot() ; //Total energy of current track
3decf5cb	489
3a4295ee	490	//Calculating mass of current particle
	491	TDatabasePDG * pdg = TDatabasePDG::Instance() ;
	492	TParticlePDG * partPDG = pdg->GetParticle(gMC->TrackPid()) ;
	493	Float_t mass = partPDG->Mass() ;
a73f33f0	494
3a4295ee	495	if(energy > mass){
	496	pos.SetMag(TMath::Sqrt(energyenergy-massmass)) ;
	497	TLorentzVector pTrack(pos, energy) ;
a73f33f0	498
3a4295ee	499	TParticle * part = new TParticle(gMC->TrackPid(), 0,-1,-1,-1,-1, pTrack, lv) ;
	500
	501	AliPHOSFastRecParticle rp(*part) ;
b1aa729d	502
3a4295ee	503	// Adds the response of PHOS to the particle
	504	MakeRecParticle(modid, pos, rp) ;
	505
	506	// add the `track' particle to the FastRecParticles list
b1aa729d	507
3a4295ee	508	AddRecParticle(rp) ;
a73f33f0	509
3a4295ee	510	part->Delete() ;
3a4295ee	511	}
a73f33f0	512	// stop the track as soon PHOS is reached
b1aa729d	513
3decf5cb	514	gMC->StopTrack() ;
	515
	516	}
	517