[u/mrichter/AliRoot.git] / EMCAL / AliEMCALGeometry.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.                  *
 **************************************************************************/

/* $Id$*/

//_________________________________________________________________________
// Geometry class  for EMCAL : singleton  
// EMCAL consists of layers of scintillator and lead
// Places the the Barrel Geometry of The EMCAL at Midrapidity
// between 0 and 120 degrees of Phi and
// -0.7 to 0.7 in eta 
// Number of Modules and Layers may be controlled by 
// the name of the instance defined               
//*-- Author: Sahal Yacoob (LBL / UCT)
//     and  : Yves Schutz (SUBATECH)
//     and  : Jennifer Klay (LBL)

// --- AliRoot header files ---
#include <TMath.h>
#include <TVector3.h>

// -- ALICE Headers.
//#include "AliConst.h"

// --- EMCAL headers
#include "AliEMCALGeometry.h"

ClassImp(AliEMCALGeometry)

AliEMCALGeometry *AliEMCALGeometry::fgGeom = 0;
Bool_t            AliEMCALGeometry::fgInit = kFALSE;

//______________________________________________________________________
AliEMCALGeometry::~AliEMCALGeometry(void){
    // dtor
}

//______________________________________________________________________
Bool_t AliEMCALGeometry::AreInSameTower(Int_t id1, Int_t id2) const {
  // Find out whether two hits are in the same tower
  Int_t idmax = TMath::Max(id1, id2) ; 
  Int_t idmin = TMath::Min(id1, id2) ;
  if ( ((idmax - GetNZ() * GetNPhi()) == idmin ) || 
       ((idmax - 2 * GetNZ() * GetNPhi()) == idmin ) )
    return kTRUE ; 
  else 
    return kFALSE ; 
}

//______________________________________________________________________
void AliEMCALGeometry::Init(void){
  // Initializes the EMCAL parameters
  // naming convention : GUV_WX_N_ gives the composition of a tower
  // WX inform about the composition of the EM calorimeter section: 
  //   thickness in mm of Pb radiator (W) and of scintillator (X), and number of scintillator layers (N)
  // New geometry: EMCAL_55_25

  fgInit = kFALSE; // Assume failed until proven otherwise.
  TString name(GetName()) ; 
  if (name == "EMCAL_55_25") {
    fECPbRadThickness  = 0.5;  // cm, Thickness of the Pb radiators
    fECScintThick      = 0.5;  // cm, Thickness of the scintillator
    fNECLayers         = 25;   // number of scintillator layers
    
    fSampling          = 13.1;  // calculated with Birk's law implementation
 
    fAlFrontThick      = 3.5;  // cm, Thickness of front Al layer
    fGap2Active        = 1.0;  // cm, Gap between Al and 1st Scintillator
  }
  else if( name == "G56_2_55_19" || name == "EMCAL_5655_21" || name == "G56_2_55_19_104_14"|| name == "G65_2_64_19" || name == "EMCAL_6564_21"){
    Fatal("Init", "%s is an old geometry! Please update your Config file", name.Data()) ;
  }
  else
    Fatal("Init", "%s is an undefined geometry!", name.Data()) ; 
		 
  // geometry
  fNZ             = 114;	// granularity along Z (eta) 
  fNPhi           = 168;	// granularity in phi (azimuth)
  fArm1PhiMin     = 60.0;	// degrees, Starting EMCAL Phi position
  fArm1PhiMax     = 180.0;	// degrees, Ending EMCAL Phi position
  fArm1EtaMin     = -0.7;	// pseudorapidity, Starting EMCAL Eta position
  fArm1EtaMax     = +0.7;	// pseudorapidity, Ending EMCAL Eta position
  
  fIPDistance     = 454.0; // cm, Radial distance to inner surface of EMCAL

  //There is always one more scintillator than radiator layer because of the first block of aluminium
  fShellThickness = fAlFrontThick + fGap2Active + fNECLayers*GetECScintThick()+(fNECLayers-1)*GetECPbRadThick();

  fZLength        = 2.*ZFromEtaR(fIPDistance+fShellThickness,fArm1EtaMax); // Z coverage
  fEnvelop[0]     = fIPDistance; // mother volume inner radius
  fEnvelop[1]     = fIPDistance + fShellThickness; // mother volume outer r.
  fEnvelop[2]     = 1.00001*fZLength; // add some padding for mother volume. 
  
  fgInit = kTRUE; 
  
  if (gDebug) {
    printf("Init: geometry of EMCAL named %s is as follows:", name.Data());
    printf( "               ECAL      : %d x (%f mm Pb, %f mm Sc) \n", GetNECLayers(), GetECPbRadThick(), GetECScintThick() ) ; 
    printf("Granularity: %d in eta and %d in phi\n", GetNZ(), GetNPhi()) ;
    printf("Layout: phi = (%f, %f), eta = (%f, %f), y = %f\n",  
	   GetArm1PhiMin(), GetArm1PhiMax(),GetArm1EtaMin(), GetArm1EtaMax(), GetIPDistance() ) ;    
  }
}

//______________________________________________________________________
AliEMCALGeometry *  AliEMCALGeometry::GetInstance(){ 
  // Returns the pointer of the unique instance
  
  return static_cast<AliEMCALGeometry *>( fgGeom ) ; 
}

//______________________________________________________________________
AliEMCALGeometry* AliEMCALGeometry::GetInstance(const Text_t* name,
						const Text_t* title){
    // Returns the pointer of the unique instance

    AliEMCALGeometry * rv = 0; 
    if ( fgGeom == 0 ) {
	if ( strcmp(name,"") == 0 ) rv = 0;
	else {    
	    fgGeom = new AliEMCALGeometry(name, title);
	    if ( fgInit ) rv = (AliEMCALGeometry * ) fgGeom;
	    else {
		rv = 0; 
		delete fgGeom; 
		fgGeom = 0; 
	    } // end if fgInit
	} // end if strcmp(name,"")
    }else{
	if ( strcmp(fgGeom->GetName(), name) != 0 ) {
	  printf("\ncurrent geometry is ") ;  
	  printf(fgGeom->GetName());
	  printf("\n                      you cannot call     "); 
	  printf(name);  
	}else{
	  rv = (AliEMCALGeometry *) fgGeom; 
	} // end if
    }  // end if fgGeom
    return rv; 
}

//______________________________________________________________________
Int_t AliEMCALGeometry::TowerIndex(Int_t ieta,Int_t iphi) const {
  // Returns the tower index number from the based on the Z and Phi
  // index numbers.
  // Inputs:
  //   Int_t ieta    // index along z axis [1-fNZ]
  //   Int_t iphi  // index along phi axis [1-fNPhi]
  // Outputs:
  //   none.
  // Returned
  //   Int_t index // Tower index number 
  
  if ( (ieta <= 0 || ieta>GetNEta()) || 
       (iphi <= 0 || iphi>GetNPhi())) {
    Error("TowerIndex", "Unexpected parameters eta = %d phi = %d!", ieta, iphi) ; 
    return -1;
  }
  return ( (iphi - 1)*GetNEta() + ieta ); 
}

//______________________________________________________________________
void AliEMCALGeometry::TowerIndexes(Int_t index,Int_t &ieta,Int_t &iphi) const {
  // Inputs:
  //   Int_t index // Tower index number [1-fNZ*fNPhi]
  // Outputs:
  //   Int_t ieta    // index allong z axis [1-fNZ]
  //   Int_t iphi  // index allong phi axis [1-fNPhi]
  // Returned
  //   none.

  Int_t nindex = 0;

  if ( IsInECA(index) ) { // ECAL index
    nindex = index ;
  }
  else {
    Error("TowerIndexes", "Unexpected Id number!") ;
    ieta = -1;
    iphi = -1;
    return;
  }   

  if (nindex%GetNZ()) 
    iphi = nindex / GetNZ() + 1 ; 
  else 
    iphi = nindex / GetNZ() ; 
  ieta = nindex - (iphi - 1) * GetNZ() ; 

  if (gDebug==2)
    printf("TowerIndexes: index=%d,%d, ieta=%d, iphi = %d", index, nindex,ieta, iphi) ; 
  return;
  
}

//______________________________________________________________________
void AliEMCALGeometry::EtaPhiFromIndex(Int_t index,Float_t &eta,Float_t &phi) const {
    // given the tower index number it returns the based on the eta and phi
    // of the tower.
    // Inputs:
    //   Int_t index // Tower index number [1-fNZ*fNPhi]
    // Outputs:
    //   Float_t eta  // eta of center of tower in pseudorapidity
    //   Float_t phi  // phi of center of tower in degrees
    // Returned
    //   none.
    Int_t ieta, iphi;
    Float_t deta, dphi ;

    TowerIndexes(index,ieta,iphi);
    
    if (gDebug == 2) 
      printf("EtaPhiFromIndex: index = %d, ieta = %d, iphi = %d", index, ieta, iphi) ;

    deta = (GetArm1EtaMax()-GetArm1EtaMin())/(static_cast<Float_t>(GetNEta()));
    eta  = GetArm1EtaMin() + ((static_cast<Float_t>(ieta) - 0.5 ))*deta;

    dphi = (GetArm1PhiMax() - GetArm1PhiMin())/(static_cast<Float_t>(GetNPhi()));  // in degrees.
    phi  = GetArm1PhiMin() + dphi*(static_cast<Float_t>(iphi) - 0.5);//iphi range [1-fNphi].
}

//______________________________________________________________________
Int_t AliEMCALGeometry::TowerIndexFromEtaPhi(Float_t eta,Float_t phi) const {
    // returns the tower index number based on the eta and phi of the tower.
    // Inputs:
    //   Float_t eta  // eta of center of tower in pseudorapidity
    //   Float_t phi  // phi of center of tower in degrees
    // Outputs:
    //   none.
    // Returned
    //   Int_t index // Tower index number [1-fNZ*fNPhi]

    Int_t ieta,iphi;

    ieta = static_cast<Int_t> ( 1 + (static_cast<Float_t>(GetNEta()) * (eta - GetArm1EtaMin()) / (GetArm1EtaMax() - GetArm1EtaMin())) ) ;

    if( ieta <= 0 || ieta > GetNEta() ) { 
      Error("TowerIndexFromEtaPhi", "Unexpected (eta, phi) = (%f, %f) value, outside of EMCAL!", eta, phi) ; 
      return -1 ; 
    }

    iphi = static_cast<Int_t> ( 1 + (static_cast<Float_t>(GetNPhi()) * (phi - GetArm1PhiMin()) / (GetArm1PhiMax() - GetArm1PhiMin())) ) ;

    if( iphi <= 0 || iphi > GetNPhi() ) { 
      Error("TowerIndexFromEtaPhi", "Unexpected (eta, phi) = (%f, %f) value, outside of EMCAL!", eta, phi) ; 
      return -1 ; 
    }

    return TowerIndex(ieta,iphi);
}

//______________________________________________________________________
Bool_t AliEMCALGeometry::AbsToRelNumbering(Int_t AbsId, Int_t *relid) const {
    // Converts the absolute numbering into the following array/
    //  relid[0] = Row number inside EMCAL
    //  relid[1] = Column number inside EMCAL
    // Input:
    //   Int_t AbsId // Tower index number [1-2*fNZ*fNPhi]
    // Outputs:
    //   Int_t *relid // array of 2. Described above.
    Bool_t rv  = kTRUE ;
    Int_t ieta=0,iphi=0,index=AbsId;

    TowerIndexes(index,ieta,iphi);
    relid[0] = ieta;
    relid[1] = iphi;

    return rv;
}

//______________________________________________________________________
void AliEMCALGeometry::PosInAlice(const Int_t *relid, Float_t &theta, Float_t &phi) const 
{
  // Converts the relative numbering into the local EMCAL-module (x, z)
  // coordinates
  Int_t ieta = relid[0]; // offset along x axis
  Int_t iphi = relid[1]; // offset along z axis
  Int_t index;
  Float_t eta;
  
  index = TowerIndex(ieta,iphi);
  EtaPhiFromIndex(index,eta,phi);
  //theta = 180.*(2.0*TMath::ATan(TMath::Exp(-eta)))/TMath::Pi();
  theta = 2.0*TMath::ATan(TMath::Exp(-eta));

  // correct for distance to IP
  Float_t d = GetIP2ECASection() - GetIPDistance() ;  

  Float_t correction = 1 + d/GetIPDistance() ; 
  Float_t tantheta = TMath::Tan(theta) * correction ; 
  theta = TMath::ATan(tantheta) * TMath::RadToDeg() ; 
  if (theta < 0 ) 
    theta += 180. ; 
  
  return;
}

//______________________________________________________________________
void AliEMCALGeometry::PosInAlice(Int_t absid, Float_t &theta, Float_t &phi) const 
{
  // Converts the relative numbering into the local EMCAL-module (x, z)
  // coordinates
  Int_t relid[2] ; 
  AbsToRelNumbering(absid, relid) ;
  Int_t ieta = relid[0]; // offset along x axis
  Int_t iphi = relid[1]; // offset along z axis
  Int_t index;
  Float_t eta;
  
  index = TowerIndex(ieta,iphi);
  EtaPhiFromIndex(index,eta,phi);
  theta = 2.0*TMath::ATan(TMath::Exp(-eta)) ;
  
  // correct for distance to IP
  Float_t d = 0. ; 
  if (IsInECA(absid))
    d = GetIP2ECASection() - GetIPDistance() ; 
  else {
    Error("PosInAlice", "Unexpected id # %d!", absid) ; 
    return;
  }

  Float_t correction = 1 + d/GetIPDistance() ; 
  Float_t tantheta = TMath::Tan(theta) * correction ; 
  theta = TMath::ATan(tantheta) * TMath::RadToDeg() ; 
  if (theta < 0 ) 
    theta += 180. ; 
  
  return;
}

//______________________________________________________________________
void AliEMCALGeometry::XYZFromIndex(const Int_t *relid,Float_t &x,Float_t &y, Float_t &z) const {
    // given the tower relative number it returns the X, Y and Z
    // of the tower.
    
    // Outputs:
    //   Float_t x  // x of center of tower in cm
    //   Float_t y  // y of center of tower in cm
    //   Float_t z  // z of centre of tower in cm
    // Returned
    //   none.
    
    Float_t eta,theta, phi,cylradius=0. ;
    
    Int_t ieta = relid[0]; // offset along x axis
    Int_t iphi = relid[1]; // offset along z axis.
    Int_t index;
    
    index = TowerIndex(ieta,iphi);
    EtaPhiFromIndex(index,eta,phi);
    theta = 180.*(2.0*TMath::ATan(TMath::Exp(-eta)))/TMath::Pi();
    
    cylradius = GetIP2ECASection() ;  

    Double_t  kDeg2Rad = TMath::DegToRad() ; 
    x =  cylradius * TMath::Cos(phi * kDeg2Rad ) ;
    y =  cylradius * TMath::Sin(phi * kDeg2Rad ) ; 
    z =  cylradius / TMath::Tan(theta * kDeg2Rad ) ; 
 
 return;
} 

//______________________________________________________________________
void AliEMCALGeometry::XYZFromIndex(Int_t absid,  TVector3 &v) const {
    // given the tower relative number it returns the X, Y and Z
    // of the tower.
    
    // Outputs:
    //   Float_t x  // x of center of tower in cm
    //   Float_t y  // y of center of tower in cm
    //   Float_t z  // z of centre of tower in cm
    // Returned
    //   none.
    
    Float_t theta, phi,cylradius=0. ;
        
    PosInAlice(absid, theta, phi) ; 
    
    if ( IsInECA(absid) ) 
      cylradius = GetIP2ECASection() ;
    else {
      Error("XYZFromIndex", "Unexpected Tower section") ;
      return;
    }

    Double_t  kDeg2Rad = TMath::DegToRad() ; 
    v.SetX(cylradius * TMath::Cos(phi * kDeg2Rad ) );
    v.SetY(cylradius * TMath::Sin(phi * kDeg2Rad ) ); 
    v.SetZ(cylradius / TMath::Tan(theta * kDeg2Rad ) ) ; 
 
 return;
} 

Bool_t AliEMCALGeometry::IsInEMCAL(Double_t x, Double_t y, Double_t z) const {
  // Checks whether point is inside the EMCal volume
  //
  // Code uses cylindrical approximation made of inner radius (for speed)
  //
  // Points behind EMCAl, i.e. R > outer radius, but eta, phi in acceptance 
  // are considered to inside

  Double_t r=sqrt(x*x+y*y);

  if ( r > fEnvelop[0] ) {
     Double_t theta;
     theta  =    TMath::ATan2(r,z);
     Double_t eta;
     if(theta == 0) 
       eta = 9999;
     else 
       eta    =   -TMath::Log(TMath::Tan(theta/2.));
     if (eta < fArm1EtaMin || eta > fArm1EtaMax)
       return 0;
 
     Double_t phi = TMath::ATan2(y,x) * 180./TMath::Pi();
     if (phi > fArm1PhiMin && phi < fArm1PhiMax)
       return 1;
  }
  return 0;
}
Commit	Line	Data
2012850d	1	/**************************************************************************
	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
	16	/* $Id$*/
	17
	18	//_________________________________________________________________________
	19	// Geometry class for EMCAL : singleton
b13bbe81	20	// EMCAL consists of layers of scintillator and lead
ffa6d63b	21	// Places the the Barrel Geometry of The EMCAL at Midrapidity
	22	// between 0 and 120 degrees of Phi and
	23	// -0.7 to 0.7 in eta
	24	// Number of Modules and Layers may be controlled by
	25	// the name of the instance defined
b13bbe81	26	//*-- Author: Sahal Yacoob (LBL / UCT)
	27	// and : Yves Schutz (SUBATECH)
	28	// and : Jennifer Klay (LBL)
2012850d	29
2012850d	30	// --- AliRoot header files ---
ca8f5bd0	31	#include <TMath.h>
116cbefd	32	#include <TVector3.h>
173558f2	33
ca8f5bd0	34	// -- ALICE Headers.
d64c959b	35	//#include "AliConst.h"
173558f2	36
ca8f5bd0	37	// --- EMCAL headers
ca8f5bd0	38	#include "AliEMCALGeometry.h"
2012850d	39
925e6570	40	ClassImp(AliEMCALGeometry)
2012850d	41
b13bbe81	42	AliEMCALGeometry *AliEMCALGeometry::fgGeom = 0;
b13bbe81	43	Bool_t AliEMCALGeometry::fgInit = kFALSE;
2012850d	44
b13bbe81	45	//______________________________________________________________________
	46	AliEMCALGeometry::~AliEMCALGeometry(void){
	47	// dtor
2012850d	48	}
b13bbe81	49
395c7ba2	50	//______________________________________________________________________
09884213	51	Bool_t AliEMCALGeometry::AreInSameTower(Int_t id1, Int_t id2) const {
fdebddeb	52	// Find out whether two hits are in the same tower
395c7ba2	53	Int_t idmax = TMath::Max(id1, id2) ;
	54	Int_t idmin = TMath::Min(id1, id2) ;
	55	if ( ((idmax - GetNZ() * GetNPhi()) == idmin ) \|\|
	56	((idmax - 2 * GetNZ() * GetNPhi()) == idmin ) )
	57	return kTRUE ;
	58	else
	59	return kFALSE ;
	60	}
05a92d59	61
395c7ba2	62	//______________________________________________________________________
	63	void AliEMCALGeometry::Init(void){
	64	// Initializes the EMCAL parameters
fdebddeb	65	// naming convention : GUV_WX_N_ gives the composition of a tower
395c7ba2	66	// WX inform about the composition of the EM calorimeter section:
fdebddeb	67	// thickness in mm of Pb radiator (W) and of scintillator (X), and number of scintillator layers (N)
fdebddeb	68	// New geometry: EMCAL_55_25
395c7ba2	69
fdebddeb	70	fgInit = kFALSE; // Assume failed until proven otherwise.
	71	TString name(GetName()) ;
	72	if (name == "EMCAL_55_25") {
	73	fECPbRadThickness = 0.5; // cm, Thickness of the Pb radiators
	74	fECScintThick = 0.5; // cm, Thickness of the scintillator
	75	fNECLayers = 25; // number of scintillator layers
395c7ba2	76
57c473a6	77	fSampling = 13.1; // calculated with Birk's law implementation
395c7ba2	78
fdebddeb	79	fAlFrontThick = 3.5; // cm, Thickness of front Al layer
395c7ba2	80	fGap2Active = 1.0; // cm, Gap between Al and 1st Scintillator
395c7ba2	81	}
fdebddeb	82	else if( name == "G56_2_55_19" \|\| name == "EMCAL_5655_21" \|\| name == "G56_2_55_19_104_14"\|\| name == "G65_2_64_19" \|\| name == "EMCAL_6564_21"){
fdebddeb	83	Fatal("Init", "%s is an old geometry! Please update your Config file", name.Data()) ;
395c7ba2	84	}
	85	else
	86	Fatal("Init", "%s is an undefined geometry!", name.Data()) ;
05a92d59	87
395c7ba2	88	// geometry
fdebddeb	89	fNZ = 114; // granularity along Z (eta)
	90	fNPhi = 168; // granularity in phi (azimuth)
	91	fArm1PhiMin = 60.0; // degrees, Starting EMCAL Phi position
	92	fArm1PhiMax = 180.0; // degrees, Ending EMCAL Phi position
	93	fArm1EtaMin = -0.7; // pseudorapidity, Starting EMCAL Eta position
	94	fArm1EtaMax = +0.7; // pseudorapidity, Ending EMCAL Eta position
395c7ba2	95
395c7ba2	96	fIPDistance = 454.0; // cm, Radial distance to inner surface of EMCAL
fdebddeb	97
	98	//There is always one more scintillator than radiator layer because of the first block of aluminium
	99	fShellThickness = fAlFrontThick + fGap2Active + fNECLayersGetECScintThick()+(fNECLayers-1)GetECPbRadThick();
	100
395c7ba2	101	fZLength = 2.*ZFromEtaR(fIPDistance+fShellThickness,fArm1EtaMax); // Z coverage
	102	fEnvelop[0] = fIPDistance; // mother volume inner radius
	103	fEnvelop[1] = fIPDistance + fShellThickness; // mother volume outer r.
	104	fEnvelop[2] = 1.00001*fZLength; // add some padding for mother volume.
	105
	106	fgInit = kTRUE;
	107
88cb7938	108	if (gDebug) {
fdebddeb	109	printf("Init: geometry of EMCAL named %s is as follows:", name.Data());
88cb7938	110	printf( " ECAL : %d x (%f mm Pb, %f mm Sc) \n", GetNECLayers(), GetECPbRadThick(), GetECScintThick() ) ;
88cb7938	111	printf("Granularity: %d in eta and %d in phi\n", GetNZ(), GetNPhi()) ;
	112	printf("Layout: phi = (%f, %f), eta = (%f, %f), y = %f\n",
	113	GetArm1PhiMin(), GetArm1PhiMax(),GetArm1EtaMin(), GetArm1EtaMax(), GetIPDistance() ) ;
	114	}
2012850d	115	}
173558f2	116
b13bbe81	117	//______________________________________________________________________
b13bbe81	118	AliEMCALGeometry * AliEMCALGeometry::GetInstance(){
05a92d59	119	// Returns the pointer of the unique instance
	120
	121	return static_cast<AliEMCALGeometry *>( fgGeom ) ;
2012850d	122	}
173558f2	123
b13bbe81	124	//______________________________________________________________________
	125	AliEMCALGeometry* AliEMCALGeometry::GetInstance(const Text_t* name,
	126	const Text_t* title){
	127	// Returns the pointer of the unique instance
	128
	129	AliEMCALGeometry * rv = 0;
	130	if ( fgGeom == 0 ) {
	131	if ( strcmp(name,"") == 0 ) rv = 0;
	132	else {
	133	fgGeom = new AliEMCALGeometry(name, title);
	134	if ( fgInit ) rv = (AliEMCALGeometry * ) fgGeom;
	135	else {
	136	rv = 0;
	137	delete fgGeom;
	138	fgGeom = 0;
	139	} // end if fgInit
	140	} // end if strcmp(name,"")
	141	}else{
	142	if ( strcmp(fgGeom->GetName(), name) != 0 ) {
fdebddeb	143	printf("\ncurrent geometry is ") ;
	144	printf(fgGeom->GetName());
	145	printf("\n you cannot call ");
	146	printf(name);
b13bbe81	147	}else{
9859bfc0	148	rv = (AliEMCALGeometry *) fgGeom;
b13bbe81	149	} // end if
	150	} // end if fgGeom
	151	return rv;
2012850d	152	}
173558f2	153
ca8f5bd0	154	//______________________________________________________________________
395c7ba2	155	Int_t AliEMCALGeometry::TowerIndex(Int_t ieta,Int_t iphi) const {
395c7ba2	156	// Returns the tower index number from the based on the Z and Phi
fdebddeb	157	// index numbers.
395c7ba2	158	// Inputs:
fdebddeb	159	// Int_t ieta // index along z axis [1-fNZ]
fdebddeb	160	// Int_t iphi // index along phi axis [1-fNPhi]
395c7ba2	161	// Outputs:
	162	// none.
	163	// Returned
	164	// Int_t index // Tower index number
	165
	166	if ( (ieta <= 0 \|\| ieta>GetNEta()) \|\|
f1da4a27	167	(iphi <= 0 \|\| iphi>GetNPhi())) {
	168	Error("TowerIndex", "Unexpected parameters eta = %d phi = %d!", ieta, iphi) ;
	169	return -1;
	170	}
395c7ba2	171	return ( (iphi - 1)*GetNEta() + ieta );
ca8f5bd0	172	}
173558f2	173
ca8f5bd0	174	//______________________________________________________________________
fdebddeb	175	void AliEMCALGeometry::TowerIndexes(Int_t index,Int_t &ieta,Int_t &iphi) const {
395c7ba2	176	// Inputs:
fdebddeb	177	// Int_t index // Tower index number [1-fNZ*fNPhi]
395c7ba2	178	// Outputs:
	179	// Int_t ieta // index allong z axis [1-fNZ]
	180	// Int_t iphi // index allong phi axis [1-fNPhi]
395c7ba2	181	// Returned
395c7ba2	182	// none.
395c7ba2	183
fdebddeb	184	Int_t nindex = 0;
395c7ba2	185
fdebddeb	186	if ( IsInECA(index) ) { // ECAL index
395c7ba2	187	nindex = index ;
395c7ba2	188	}
f1da4a27	189	else {
	190	Error("TowerIndexes", "Unexpected Id number!") ;
	191	ieta = -1;
	192	iphi = -1;
	193	return;
	194	}
	195
395c7ba2	196	if (nindex%GetNZ())
	197	iphi = nindex / GetNZ() + 1 ;
	198	else
	199	iphi = nindex / GetNZ() ;
	200	ieta = nindex - (iphi - 1) * GetNZ() ;
	201
	202	if (gDebug==2)
fdebddeb	203	printf("TowerIndexes: index=%d,%d, ieta=%d, iphi = %d", index, nindex,ieta, iphi) ;
395c7ba2	204	return;
395c7ba2	205
ca8f5bd0	206	}
173558f2	207
ca8f5bd0	208	//______________________________________________________________________
a34b7b9f	209	void AliEMCALGeometry::EtaPhiFromIndex(Int_t index,Float_t &eta,Float_t &phi) const {
ca8f5bd0	210	// given the tower index number it returns the based on the eta and phi
	211	// of the tower.
	212	// Inputs:
fdebddeb	213	// Int_t index // Tower index number [1-fNZ*fNPhi]
ca8f5bd0	214	// Outputs:
	215	// Float_t eta // eta of center of tower in pseudorapidity
	216	// Float_t phi // phi of center of tower in degrees
	217	// Returned
	218	// none.
fdebddeb	219	Int_t ieta, iphi;
395c7ba2	220	Float_t deta, dphi ;
ca8f5bd0	221
fdebddeb	222	TowerIndexes(index,ieta,iphi);
395c7ba2	223
395c7ba2	224	if (gDebug == 2)
fdebddeb	225	printf("EtaPhiFromIndex: index = %d, ieta = %d, iphi = %d", index, ieta, iphi) ;
395c7ba2	226
	227	deta = (GetArm1EtaMax()-GetArm1EtaMin())/(static_cast<Float_t>(GetNEta()));
	228	eta = GetArm1EtaMin() + ((static_cast<Float_t>(ieta) - 0.5 ))*deta;
	229
	230	dphi = (GetArm1PhiMax() - GetArm1PhiMin())/(static_cast<Float_t>(GetNPhi())); // in degrees.
	231	phi = GetArm1PhiMin() + dphi*(static_cast<Float_t>(iphi) - 0.5);//iphi range [1-fNphi].
ca8f5bd0	232	}
173558f2	233
ca8f5bd0	234	//______________________________________________________________________
a34b7b9f	235	Int_t AliEMCALGeometry::TowerIndexFromEtaPhi(Float_t eta,Float_t phi) const {
ca8f5bd0	236	// returns the tower index number based on the eta and phi of the tower.
	237	// Inputs:
	238	// Float_t eta // eta of center of tower in pseudorapidity
	239	// Float_t phi // phi of center of tower in degrees
	240	// Outputs:
	241	// none.
	242	// Returned
	243	// Int_t index // Tower index number [1-fNZ*fNPhi]
395c7ba2	244
e908f07f	245	Int_t ieta,iphi;
ca8f5bd0	246
395c7ba2	247	ieta = static_cast<Int_t> ( 1 + (static_cast<Float_t>(GetNEta()) * (eta - GetArm1EtaMin()) / (GetArm1EtaMax() - GetArm1EtaMin())) ) ;
	248
	249	if( ieta <= 0 \|\| ieta > GetNEta() ) {
	250	Error("TowerIndexFromEtaPhi", "Unexpected (eta, phi) = (%f, %f) value, outside of EMCAL!", eta, phi) ;
	251	return -1 ;
	252	}
	253
	254	iphi = static_cast<Int_t> ( 1 + (static_cast<Float_t>(GetNPhi()) * (phi - GetArm1PhiMin()) / (GetArm1PhiMax() - GetArm1PhiMin())) ) ;
	255
	256	if( iphi <= 0 \|\| iphi > GetNPhi() ) {
	257	Error("TowerIndexFromEtaPhi", "Unexpected (eta, phi) = (%f, %f) value, outside of EMCAL!", eta, phi) ;
	258	return -1 ;
	259	}
	260
	261	return TowerIndex(ieta,iphi);
ca8f5bd0	262	}
173558f2	263
ca8f5bd0	264	//______________________________________________________________________
a34b7b9f	265	Bool_t AliEMCALGeometry::AbsToRelNumbering(Int_t AbsId, Int_t *relid) const {
ca8f5bd0	266	// Converts the absolute numbering into the following array/
2608a1fc	267	// relid[0] = Row number inside EMCAL
2608a1fc	268	// relid[1] = Column number inside EMCAL
ca8f5bd0	269	// Input:
	270	// Int_t AbsId // Tower index number [1-2fNZfNPhi]
	271	// Outputs:
2608a1fc	272	// Int_t *relid // array of 2. Described above.
ca8f5bd0	273	Bool_t rv = kTRUE ;
fdebddeb	274	Int_t ieta=0,iphi=0,index=AbsId;
ca8f5bd0	275
fdebddeb	276	TowerIndexes(index,ieta,iphi);
2608a1fc	277	relid[0] = ieta;
2608a1fc	278	relid[1] = iphi;
ca8f5bd0	279
	280	return rv;
	281	}
173558f2	282
ca8f5bd0	283	//______________________________________________________________________
395c7ba2	284	void AliEMCALGeometry::PosInAlice(const Int_t *relid, Float_t &theta, Float_t &phi) const
	285	{
	286	// Converts the relative numbering into the local EMCAL-module (x, z)
	287	// coordinates
2608a1fc	288	Int_t ieta = relid[0]; // offset along x axis
2608a1fc	289	Int_t iphi = relid[1]; // offset along z axis
395c7ba2	290	Int_t index;
	291	Float_t eta;
	292
	293	index = TowerIndex(ieta,iphi);
	294	EtaPhiFromIndex(index,eta,phi);
fdebddeb	295	//theta = 180.(2.0TMath::ATan(TMath::Exp(-eta)))/TMath::Pi();
fdebddeb	296	theta = 2.0*TMath::ATan(TMath::Exp(-eta));
395c7ba2	297
fdebddeb	298	// correct for distance to IP
fdebddeb	299	Float_t d = GetIP2ECASection() - GetIPDistance() ;
395c7ba2	300
	301	Float_t correction = 1 + d/GetIPDistance() ;
	302	Float_t tantheta = TMath::Tan(theta) * correction ;
	303	theta = TMath::ATan(tantheta) * TMath::RadToDeg() ;
	304	if (theta < 0 )
	305	theta += 180. ;
	306
	307	return;
	308	}
ca8f5bd0	309
395c7ba2	310	//______________________________________________________________________
09884213	311	void AliEMCALGeometry::PosInAlice(Int_t absid, Float_t &theta, Float_t &phi) const
395c7ba2	312	{
	313	// Converts the relative numbering into the local EMCAL-module (x, z)
	314	// coordinates
2608a1fc	315	Int_t relid[2] ;
395c7ba2	316	AbsToRelNumbering(absid, relid) ;
2608a1fc	317	Int_t ieta = relid[0]; // offset along x axis
2608a1fc	318	Int_t iphi = relid[1]; // offset along z axis
395c7ba2	319	Int_t index;
	320	Float_t eta;
	321
	322	index = TowerIndex(ieta,iphi);
	323	EtaPhiFromIndex(index,eta,phi);
	324	theta = 2.0*TMath::ATan(TMath::Exp(-eta)) ;
	325
fdebddeb	326	// correct for distance to IP
395c7ba2	327	Float_t d = 0. ;
fdebddeb	328	if (IsInECA(absid))
88cb7938	329	d = GetIP2ECASection() - GetIPDistance() ;
f1da4a27	330	else {
	331	Error("PosInAlice", "Unexpected id # %d!", absid) ;
	332	return;
	333	}
395c7ba2	334
	335	Float_t correction = 1 + d/GetIPDistance() ;
	336	Float_t tantheta = TMath::Tan(theta) * correction ;
	337	theta = TMath::ATan(tantheta) * TMath::RadToDeg() ;
	338	if (theta < 0 )
	339	theta += 180. ;
	340
	341	return;
ca8f5bd0	342	}
6119e5db	343
	344	//______________________________________________________________________
	345	void AliEMCALGeometry::XYZFromIndex(const Int_t *relid,Float_t &x,Float_t &y, Float_t &z) const {
	346	// given the tower relative number it returns the X, Y and Z
	347	// of the tower.
	348
	349	// Outputs:
	350	// Float_t x // x of center of tower in cm
	351	// Float_t y // y of center of tower in cm
	352	// Float_t z // z of centre of tower in cm
	353	// Returned
	354	// none.
	355
fdebddeb	356	Float_t eta,theta, phi,cylradius=0. ;
6119e5db	357
2608a1fc	358	Int_t ieta = relid[0]; // offset along x axis
2608a1fc	359	Int_t iphi = relid[1]; // offset along z axis.
6119e5db	360	Int_t index;
6119e5db	361
395c7ba2	362	index = TowerIndex(ieta,iphi);
6119e5db	363	EtaPhiFromIndex(index,eta,phi);
6119e5db	364	theta = 180.(2.0TMath::ATan(TMath::Exp(-eta)))/TMath::Pi();
6119e5db	365
fdebddeb	366	cylradius = GetIP2ECASection() ;
a97849a9	367
395c7ba2	368	Double_t kDeg2Rad = TMath::DegToRad() ;
fdebddeb	369	x = cylradius * TMath::Cos(phi * kDeg2Rad ) ;
	370	y = cylradius * TMath::Sin(phi * kDeg2Rad ) ;
	371	z = cylradius / TMath::Tan(theta * kDeg2Rad ) ;
6119e5db	372
	373	return;
	374	}
	375
395c7ba2	376	//______________________________________________________________________
09884213	377	void AliEMCALGeometry::XYZFromIndex(Int_t absid, TVector3 &v) const {
395c7ba2	378	// given the tower relative number it returns the X, Y and Z
	379	// of the tower.
	380
	381	// Outputs:
	382	// Float_t x // x of center of tower in cm
	383	// Float_t y // y of center of tower in cm
	384	// Float_t z // z of centre of tower in cm
	385	// Returned
	386	// none.
	387
fdebddeb	388	Float_t theta, phi,cylradius=0. ;
395c7ba2	389
	390	PosInAlice(absid, theta, phi) ;
	391
88cb7938	392	if ( IsInECA(absid) )
fdebddeb	393	cylradius = GetIP2ECASection() ;
f1da4a27	394	else {
	395	Error("XYZFromIndex", "Unexpected Tower section") ;
	396	return;
	397	}
395c7ba2	398
395c7ba2	399	Double_t kDeg2Rad = TMath::DegToRad() ;
fdebddeb	400	v.SetX(cylradius * TMath::Cos(phi * kDeg2Rad ) );
	401	v.SetY(cylradius * TMath::Sin(phi * kDeg2Rad ) );
	402	v.SetZ(cylradius / TMath::Tan(theta * kDeg2Rad ) ) ;
395c7ba2	403
	404	return;
	405	}
ab37d09c	406
	407	Bool_t AliEMCALGeometry::IsInEMCAL(Double_t x, Double_t y, Double_t z) const {
	408	// Checks whether point is inside the EMCal volume
	409	//
	410	// Code uses cylindrical approximation made of inner radius (for speed)
	411	//
	412	// Points behind EMCAl, i.e. R > outer radius, but eta, phi in acceptance
	413	// are considered to inside
	414
	415	Double_t r=sqrt(xx+yy);
	416
	417	if ( r > fEnvelop[0] ) {
	418	Double_t theta;
	419	theta = TMath::ATan2(r,z);
	420	Double_t eta;
	421	if(theta == 0)
	422	eta = 9999;
	423	else
	424	eta = -TMath::Log(TMath::Tan(theta/2.));
	425	if (eta < fArm1EtaMin \|\| eta > fArm1EtaMax)
	426	return 0;
	427
	428	Double_t phi = TMath::ATan2(y,x) * 180./TMath::Pi();
	429	if (phi > fArm1PhiMin && phi < fArm1PhiMax)
	430	return 1;
	431	}
	432	return 0;
	433	}