X-Git-Url: http://git.uio.no/git/?a=blobdiff_plain;f=TRD%2FAliTRDv1.cxx;h=a963c21c05986fb5169585e6d0d852a6f661dcb8;hb=d5c9a22c384e2ab9fb589650a71cea4ffa9bb8ac;hp=5e064548494ead14065bccb7385f0121efe9aef8;hpb=769257f4433531300f75afd32bbb3729fc42b80f;p=u%2Fmrichter%2FAliRoot.git
diff --git a/TRD/AliTRDv1.cxx b/TRD/AliTRDv1.cxx
index 5e064548494..a963c21c059 100644
--- a/TRD/AliTRDv1.cxx
+++ b/TRD/AliTRDv1.cxx
@@ -13,164 +13,74 @@
* provided "as is" without express or implied warranty. *
**************************************************************************/
-/*
-$Log$
-Revision 1.23 2000/11/01 14:53:21 cblume
-Merge with TRD-develop
+/* $Id$ */
-Revision 1.17.2.5 2000/10/15 23:40:01 cblume
-Remove AliTRDconst
-
-Revision 1.17.2.4 2000/10/06 16:49:46 cblume
-Made Getters const
-
-Revision 1.17.2.3 2000/10/04 16:34:58 cblume
-Replace include files by forward declarations
-
-Revision 1.17.2.2 2000/09/18 13:50:17 cblume
-Include TR photon generation and adapt to new AliTRDhit
-
-Revision 1.22 2000/06/27 13:08:50 cblume
-Changed to Copy(TObject &A) to appease the HP-compiler
-
-Revision 1.21 2000/06/09 11:10:07 cblume
-Compiler warnings and coding conventions, next round
-
-Revision 1.20 2000/06/08 18:32:58 cblume
-Make code compliant to coding conventions
-
-Revision 1.19 2000/06/07 16:27:32 cblume
-Try to remove compiler warnings on Sun and HP
-
-Revision 1.18 2000/05/08 16:17:27 cblume
-Merge TRD-develop
-
-Revision 1.17.2.1 2000/05/08 14:59:16 cblume
-Made inline function non-virtual. Bug fix in setting sensitive chamber
-
-Revision 1.17 2000/02/28 19:10:26 cblume
-Include the new TRD classes
-
-Revision 1.16.4.1 2000/02/28 18:04:35 cblume
-Change to new hit version, introduce geometry class, and move digitization and clustering to AliTRDdigitizer/AliTRDclusterizerV1
-
-Revision 1.16 1999/11/05 22:50:28 fca
-Do not use Atan, removed from ROOT too
-
-Revision 1.15 1999/11/02 17:20:19 fca
-initialise nbytes before using it
-
-Revision 1.14 1999/11/02 17:15:54 fca
-Correct ansi scoping not accepted by HP compilers
-
-Revision 1.13 1999/11/02 17:14:51 fca
-Correct ansi scoping not accepted by HP compilers
-
-Revision 1.12 1999/11/02 16:35:56 fca
-New version of TRD introduced
-
-Revision 1.11 1999/11/01 20:41:51 fca
-Added protections against using the wrong version of FRAME
-
-Revision 1.10 1999/09/29 09:24:35 fca
-Introduction of the Copyright and cvs Log
-
-*/
-
-///////////////////////////////////////////////////////////////////////////////
-// //
-// Transition Radiation Detector version 1 -- slow simulator //
-// //
-//Begin_Html
-/*
-
-*/
-//End_Html
-// //
-// //
-///////////////////////////////////////////////////////////////////////////////
+////////////////////////////////////////////////////////////////////////////
+// //
+// Transition Radiation Detector version 1 -- slow simulator //
+// //
+////////////////////////////////////////////////////////////////////////////
#include
+#include
+#include
#include
-#include
#include
-#include
+#include
+#include
+#include
-#include "AliRun.h"
-#include "AliMC.h"
#include "AliConst.h"
+#include "AliLog.h"
+#include "AliMC.h"
+#include "AliRun.h"
-#include "AliTRDv1.h"
-#include "AliTRDhit.h"
-#include "AliTRDmatrix.h"
#include "AliTRDgeometry.h"
+#include "AliTRDhit.h"
#include "AliTRDsim.h"
+#include "AliTRDv1.h"
ClassImp(AliTRDv1)
//_____________________________________________________________________________
-AliTRDv1::AliTRDv1():AliTRD()
+AliTRDv1::AliTRDv1()
+ :AliTRD()
+ ,fTRon(kFALSE)
+ ,fTR(NULL)
+ ,fTypeOfStepManager(0)
+ ,fStepSize(0)
+ ,fDeltaE(NULL)
+ ,fDeltaG(NULL)
+ ,fTrackLength0(0)
+ ,fPrimaryTrackPid(0)
{
//
// Default constructor
//
- fIdSens = 0;
-
- fIdChamber1 = 0;
- fIdChamber2 = 0;
- fIdChamber3 = 0;
-
- fSensSelect = 0;
- fSensPlane = -1;
- fSensChamber = -1;
- fSensSector = -1;
- fSensSectorRange = 0;
-
- fDeltaE = NULL;
- fTR = NULL;
-
}
//_____________________________________________________________________________
AliTRDv1::AliTRDv1(const char *name, const char *title)
- :AliTRD(name, title)
+ :AliTRD(name,title)
+ ,fTRon(kTRUE)
+ ,fTR(NULL)
+ ,fTypeOfStepManager(2)
+ ,fStepSize(0.1)
+ ,fDeltaE(NULL)
+ ,fDeltaG(NULL)
+ ,fTrackLength0(0)
+ ,fPrimaryTrackPid(0)
{
//
// Standard constructor for Transition Radiation Detector version 1
//
- fIdSens = 0;
-
- fIdChamber1 = 0;
- fIdChamber2 = 0;
- fIdChamber3 = 0;
-
- fSensSelect = 0;
- fSensPlane = -1;
- fSensChamber = -1;
- fSensSector = -1;
- fSensSectorRange = 0;
-
- fDeltaE = NULL;
- fTR = NULL;
-
SetBufferSize(128000);
}
-//_____________________________________________________________________________
-AliTRDv1::AliTRDv1(const AliTRDv1 &trd)
-{
- //
- // Copy constructor
- //
-
- ((AliTRDv1 &) trd).Copy(*this);
-
-}
-
//_____________________________________________________________________________
AliTRDv1::~AliTRDv1()
{
@@ -178,44 +88,98 @@ AliTRDv1::~AliTRDv1()
// AliTRDv1 destructor
//
- if (fDeltaE) delete fDeltaE;
- if (fTR) delete fTR;
+ if (fDeltaE) {
+ delete fDeltaE;
+ fDeltaE = 0;
+ }
+
+ if (fDeltaG) {
+ delete fDeltaG;
+ fDeltaG = 0;
+ }
+
+ if (fTR) {
+ delete fTR;
+ fTR = 0;
+ }
}
//_____________________________________________________________________________
-AliTRDv1 &AliTRDv1::operator=(const AliTRDv1 &trd)
+void AliTRDv1::AddAlignableVolumes() const
{
//
- // Assignment operator
+ // Create entries for alignable volumes associating the symbolic volume
+ // name with the corresponding volume path. Needs to be syncronized with
+ // eventual changes in the geometry.
//
- if (this != &trd) ((AliTRDv1 &) trd).Copy(*this);
- return *this;
+ TString volPath;
+ TString symName;
+
+ TString vpStr = "ALIC_1/B077_1/BSEGMO";
+ TString vpApp1 = "_1/BTRD";
+ TString vpApp2 = "_1";
+ TString vpApp3 = "/UTR1_1/UTS1_1/UTI1_1/UT";
+
+ TString snStr = "TRD/sm";
+ TString snApp1 = "/st";
+ TString snApp2 = "/pl";
-}
-
-//_____________________________________________________________________________
-void AliTRDv1::Copy(TObject &trd)
-{
//
- // Copy function
+ // The super modules
+ // The symbolic names are: TRD/sm00
+ // ...
+ // TRD/sm17
//
+ for (Int_t isect = 0; isect < AliTRDgeometry::Nsect(); isect++) {
- ((AliTRDv1 &) trd).fIdSens = fIdSens;
+ volPath = vpStr;
+ volPath += isect;
+ volPath += vpApp1;
+ volPath += isect;
+ volPath += vpApp2;
- ((AliTRDv1 &) trd).fIdChamber1 = fIdChamber1;
- ((AliTRDv1 &) trd).fIdChamber2 = fIdChamber2;
- ((AliTRDv1 &) trd).fIdChamber3 = fIdChamber3;
+ symName = snStr;
+ symName += Form("%02d",isect);
- ((AliTRDv1 &) trd).fSensSelect = fSensSelect;
- ((AliTRDv1 &) trd).fSensPlane = fSensPlane;
- ((AliTRDv1 &) trd).fSensChamber = fSensChamber;
- ((AliTRDv1 &) trd).fSensSector = fSensSector;
- ((AliTRDv1 &) trd).fSensSectorRange = fSensSectorRange;
+ gGeoManager->SetAlignableEntry(symName.Data(),volPath.Data());
+
+ }
+
+ //
+ // The readout chambers
+ // The symbolic names are: TRD/sm00/st0/pl0
+ // ...
+ // TRD/sm17/st4/pl5
+ //
+ for (Int_t isect = 0; isect < AliTRDgeometry::Nsect(); isect++) {
+ for (Int_t icham = 0; icham < AliTRDgeometry::Ncham(); icham++) {
+ for (Int_t iplan = 0; iplan < AliTRDgeometry::Nplan(); iplan++) {
+
+ Int_t idet = AliTRDgeometry::GetDetectorSec(iplan,icham);
+
+ volPath = vpStr;
+ volPath += isect;
+ volPath += vpApp1;
+ volPath += isect;
+ volPath += vpApp2;
+ volPath += vpApp3;
+ volPath += Form("%02d",idet);
+ volPath += vpApp2;
+
+ symName = snStr;
+ symName += Form("%02d",isect);
+ symName += snApp1;
+ symName += icham;
+ symName += snApp2;
+ symName += iplan;
+
+ gGeoManager->SetAlignableEntry(symName.Data(),volPath.Data());
- fDeltaE->Copy(*((AliTRDv1 &) trd).fDeltaE);
- fTR->Copy(*((AliTRDv1 &) trd).fTR);
+ }
+ }
+ }
}
@@ -229,7 +193,10 @@ void AliTRDv1::CreateGeometry()
// Check that FRAME is there otherwise we have no place where to put the TRD
AliModule* frame = gAlice->GetModule("FRAME");
- if (!frame) return;
+ if (!frame) {
+ AliError("TRD needs FRAME to be present\n");
+ return;
+ }
// Define the chambers
AliTRD::CreateGeometry();
@@ -258,87 +225,83 @@ void AliTRDv1::CreateTRhit(Int_t det)
// volume.
//
- // PDG code electron
- const Int_t kPdgElectron = 11;
-
// Ionization energy
- const Float_t kWion = 22.04;
+ const Float_t kWion = 23.53;
// Maximum number of TR photons per track
const Int_t kNTR = 50;
- TLorentzVector mom, pos;
- TClonesArray &lhits = *fHits;
-
- // Create TR only for electrons
- Int_t iPdg = gMC->TrackPid();
- if (TMath::Abs(iPdg) != kPdgElectron) return;
+ TLorentzVector mom;
+ TLorentzVector pos;
- // Create TR at the entrance of the chamber
- if (gMC->IsTrackEntering()) {
+ Float_t eTR[kNTR];
+ Int_t nTR;
- Float_t eTR[kNTR];
- Int_t nTR;
+ // Create TR photons
+ gMC->TrackMomentum(mom);
+ Float_t pTot = mom.Rho();
+ fTR->CreatePhotons(11,pTot,nTR,eTR);
+ if (nTR > kNTR) {
+ AliFatal(Form("Boundary error: nTR = %d, kNTR = %d",nTR,kNTR));
+ }
- // Create TR photons
- gMC->TrackMomentum(mom);
- Float_t pTot = mom.Rho();
- fTR->CreatePhotons(iPdg,pTot,nTR,eTR);
- if (nTR > kNTR) {
- printf("AliTRDv1::CreateTRhit -- ");
- printf("Boundary error: nTR = %d, kNTR = %d\n",nTR,kNTR);
- exit(1);
+ // Loop through the TR photons
+ for (Int_t iTR = 0; iTR < nTR; iTR++) {
+
+ Float_t energyMeV = eTR[iTR] * 0.001;
+ Float_t energyeV = eTR[iTR] * 1000.0;
+ Float_t absLength = 0.0;
+ Float_t sigma = 0.0;
+
+ // Take the absorbtion in the entrance window into account
+ Double_t muMy = fTR->GetMuMy(energyMeV);
+ sigma = muMy * fFoilDensity;
+ if (sigma > 0.0) {
+ absLength = gRandom->Exp(1.0/sigma);
+ if (absLength < AliTRDgeometry::MyThick()) {
+ continue;
+ }
+ }
+ else {
+ continue;
}
- // Loop through the TR photons
- for (Int_t iTR = 0; iTR < nTR; iTR++) {
-
- Float_t energyMeV = eTR[iTR] * 0.001;
- Float_t energyeV = eTR[iTR] * 1000.0;
- Float_t absLength = 0;
- Float_t sigma = 0;
-
- // Take the absorbtion in the entrance window into account
- Double_t muMy = fTR->GetMuMy(energyMeV);
- sigma = muMy * fFoilDensity;
- absLength = gRandom->Exp(sigma);
- if (absLength < AliTRDgeometry::MyThick()) continue;
-
- // The absorbtion cross sections in the drift gas
- if (fGasMix == 1) {
- // Gas-mixture (Xe/CO2)
- Double_t muXe = fTR->GetMuXe(energyMeV);
- Double_t muCO = fTR->GetMuCO(energyMeV);
- sigma = (0.90 * muXe + 0.10 * muCO) * fGasDensity;
+ // The absorbtion cross sections in the drift gas
+ // Gas-mixture (Xe/CO2)
+ Double_t muXe = fTR->GetMuXe(energyMeV);
+ Double_t muCO = fTR->GetMuCO(energyMeV);
+ sigma = (0.85 * muXe + 0.15 * muCO) * fGasDensity * fTR->GetTemp();
+
+ // The distance after which the energy of the TR photon
+ // is deposited.
+ if (sigma > 0.0) {
+ absLength = gRandom->Exp(1.0/sigma);
+ if (absLength > (AliTRDgeometry::DrThick()
+ + AliTRDgeometry::AmThick())) {
+ continue;
}
- else {
- // Gas-mixture (Xe/Isobutane)
- Double_t muXe = fTR->GetMuXe(energyMeV);
- Double_t muBu = fTR->GetMuBu(energyMeV);
- sigma = (0.97 * muXe + 0.03 * muBu) * fGasDensity;
- }
-
- // The distance after which the energy of the TR photon
- // is deposited.
- absLength = gRandom->Exp(sigma);
- if (absLength > AliTRDgeometry::DrThick()) continue;
-
- // The position of the absorbtion
- Float_t posHit[3];
- gMC->TrackPosition(pos);
- posHit[0] = pos[0] + mom[0] / pTot * absLength;
- posHit[1] = pos[1] + mom[1] / pTot * absLength;
- posHit[2] = pos[2] + mom[2] / pTot * absLength;
+ }
+ else {
+ continue;
+ }
- // Create the charge
- Int_t q = ((Int_t) (energyeV / kWion));
+ // The position of the absorbtion
+ Float_t posHit[3];
+ gMC->TrackPosition(pos);
+ posHit[0] = pos[0] + mom[0] / pTot * absLength;
+ posHit[1] = pos[1] + mom[1] / pTot * absLength;
+ posHit[2] = pos[2] + mom[2] / pTot * absLength;
- // Add the hit to the array. TR photon hits are marked
- // by negative charge
- new(lhits[fNhits++]) AliTRDhit(fIshunt,gAlice->CurrentTrack()
- ,det,posHit,-q);
+ // Create the charge
+ Int_t q = ((Int_t) (energyeV / kWion));
- }
+ // Add the hit to the array. TR photon hits are marked
+ // by negative charge
+ AddHit(gAlice->GetMCApp()->GetCurrentTrackNumber()
+ ,det
+ ,posHit
+ ,-q
+ ,kTRUE);
}
@@ -353,146 +316,334 @@ void AliTRDv1::Init()
AliTRD::Init();
- printf(" Slow simulator\n\n");
- if (fSensSelect) {
- if (fSensPlane >= 0)
- printf(" Only plane %d is sensitive\n",fSensPlane);
- if (fSensChamber >= 0)
- printf(" Only chamber %d is sensitive\n",fSensChamber);
- if (fSensSector >= 0) {
- Int_t sens1 = fSensSector;
- Int_t sens2 = fSensSector + fSensSectorRange;
- sens2 -= ((Int_t) (sens2 / AliTRDgeometry::Nsect()))
- * AliTRDgeometry::Nsect();
- printf(" Only sectors %d - %d are sensitive\n",sens1,sens2-1);
- }
+ AliDebug(1,"Slow simulator\n");
+
+ // Switch on TR simulation as default
+ if (!fTRon) {
+ AliInfo("TR simulation off");
+ }
+ else {
+ fTR = new AliTRDsim();
}
- if (fTR)
- printf(" TR simulation on\n");
- else
- printf(" TR simulation off\n");
- printf("\n");
// First ionization potential (eV) for the gas mixture (90% Xe + 10% CO2)
const Float_t kPoti = 12.1;
// Maximum energy (50 keV);
const Float_t kEend = 50000.0;
// Ermilova distribution for the delta-ray spectrum
- Float_t poti = TMath::Log(kPoti);
- Float_t eEnd = TMath::Log(kEend);
- fDeltaE = new TF1("deltae",Ermilova,poti,eEnd,0);
+ Float_t poti = TMath::Log(kPoti);
+ Float_t eEnd = TMath::Log(kEend);
- // Identifier of the sensitive volume (drift region)
- fIdSens = gMC->VolId("UL05");
+ // Ermilova distribution for the delta-ray spectrum
+ fDeltaE = new TF1("deltae" ,Ermilova ,poti,eEnd,0);
- // Identifier of the TRD-driftchambers
- fIdChamber1 = gMC->VolId("UCIO");
- fIdChamber2 = gMC->VolId("UCIM");
- fIdChamber3 = gMC->VolId("UCII");
+ // Geant3 distribution for the delta-ray spectrum
+ fDeltaG = new TF1("deltag",IntSpecGeant,2.421257,28.536469,0);
- for (Int_t i = 0; i < 80; i++) printf("*");
- printf("\n");
+ AliDebug(1,"+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++");
}
//_____________________________________________________________________________
-AliTRDsim *AliTRDv1::CreateTR()
+void AliTRDv1::StepManager()
{
//
- // Enables the simulation of TR
+ // Slow simulator. Every charged track produces electron cluster as hits
+ // along its path across the drift volume.
//
- fTR = new AliTRDsim();
- return fTR;
+ switch (fTypeOfStepManager) {
+ case 0:
+ StepManagerErmilova();
+ break;
+ case 1:
+ StepManagerGeant();
+ break;
+ case 2:
+ StepManagerFixedStep();
+ break;
+ default:
+ AliWarning("Not a valid Step Manager.");
+ }
}
//_____________________________________________________________________________
-void AliTRDv1::SetSensPlane(Int_t iplane)
+void AliTRDv1::SelectStepManager(Int_t t)
{
//
- // Defines the hit-sensitive plane (0-5)
+ // Selects a step manager type:
+ // 0 - Ermilova
+ // 1 - Geant3
+ // 2 - Fixed step size
//
- if ((iplane < 0) || (iplane > 5)) {
- printf("Wrong input value: %d\n",iplane);
- printf("Use standard setting\n");
- fSensPlane = -1;
- fSensSelect = 0;
- return;
- }
-
- fSensSelect = 1;
- fSensPlane = iplane;
+ fTypeOfStepManager = t;
+ AliInfo(Form("Step Manager type %d was selected",fTypeOfStepManager));
}
//_____________________________________________________________________________
-void AliTRDv1::SetSensChamber(Int_t ichamber)
+void AliTRDv1::StepManagerGeant()
{
//
- // Defines the hit-sensitive chamber (0-4)
+ // Slow simulator. Every charged track produces electron cluster as hits
+ // along its path across the drift volume. The step size is set acording
+ // to Bethe-Bloch. The energy distribution of the delta electrons follows
+ // a spectrum taken from Geant3.
+ //
+ // Version by A. Bercuci
//
- if ((ichamber < 0) || (ichamber > 4)) {
- printf("Wrong input value: %d\n",ichamber);
- printf("Use standard setting\n");
- fSensChamber = -1;
- fSensSelect = 0;
- return;
- }
+ Int_t pla = 0;
+ Int_t cha = 0;
+ Int_t sec = 0;
+ Int_t det = 0;
+ Int_t iPdg;
+ Int_t qTot;
- fSensSelect = 1;
- fSensChamber = ichamber;
+ Float_t hits[3];
+ Float_t charge;
+ Float_t aMass;
-}
+ Double_t pTot = 0;
+ Double_t eDelta;
+ Double_t betaGamma;
+ Double_t pp;
+ Double_t stepSize = 0;
+
+ Bool_t drRegion = kFALSE;
+ Bool_t amRegion = kFALSE;
+
+ TString cIdCurrent;
+ TString cIdSensDr = "J";
+ TString cIdSensAm = "K";
+ Char_t cIdChamber[3];
+ cIdChamber[2] = 0;
+
+ TLorentzVector pos;
+ TLorentzVector mom;
+
+ TArrayI processes;
+
+ const Int_t kNplan = AliTRDgeometry::Nplan();
+ const Int_t kNcham = AliTRDgeometry::Ncham();
+ const Int_t kNdetsec = kNplan * kNcham;
+
+ const Double_t kBig = 1.0e+12; // Infinitely big
+ const Float_t kWion = 23.53; // Ionization energy
+ const Float_t kPTotMaxEl = 0.002; // Maximum momentum for e+ e- g
+
+ // Minimum energy for the step size adjustment
+ const Float_t kEkinMinStep = 1.0e-5;
+ // energy threshold for production of delta electrons
+ const Float_t kECut = 1.0e4;
+ // Parameters entering the parametrized range for delta electrons
+ const Float_t kRa = 5.37e-4;
+ const Float_t kRb = 0.9815;
+ const Float_t kRc = 3.123e-3;
+ // Gas density -> To be made user adjustable !
+ // [0.85*0.00549+0.15*0.00186 (Xe-CO2 85-15)]
+ const Float_t kRho = 0.004945 ;
-//_____________________________________________________________________________
-void AliTRDv1::SetSensSector(Int_t isector)
-{
- //
- // Defines the hit-sensitive sector (0-17)
- //
+ // Plateau value of the energy-loss for electron in xenon
+ // The averaged value (26/3/99)
+ const Float_t kPlateau = 1.55;
+ // dN1/dx|min for the gas mixture (90% Xe + 10% CO2)
+ const Float_t kPrim = 19.34;
+ // First ionization potential (eV) for the gas mixture (90% Xe + 10% CO2)
+ const Float_t kPoti = 12.1;
+ // PDG code electron
+ const Int_t kPdgElectron = 11;
- SetSensSector(isector,1);
+ // Set the maximum step size to a very large number for all
+ // neutral particles and those outside the driftvolume
+ gMC->SetMaxStep(kBig);
-}
+ // Use only charged tracks
+ if (( gMC->TrackCharge() ) &&
+ (!gMC->IsTrackDisappeared())) {
-//_____________________________________________________________________________
-void AliTRDv1::SetSensSector(Int_t isector, Int_t nsector)
-{
- //
- // Defines a range of hit-sensitive sectors. The range is defined by
- // (0-17) as the starting point and as the number
- // of sectors to be included.
- //
+ // Inside a sensitive volume?
+ drRegion = kFALSE;
+ amRegion = kFALSE;
+ cIdCurrent = gMC->CurrentVolName();
+ if (cIdSensDr == cIdCurrent[1]) {
+ drRegion = kTRUE;
+ }
+ if (cIdSensAm == cIdCurrent[1]) {
+ amRegion = kTRUE;
+ }
+ if (drRegion || amRegion) {
- if ((isector < 0) || (isector > 17)) {
- printf("Wrong input value : %d\n",isector);
- printf("Use standard setting\n");
- fSensSector = -1;
- fSensSectorRange = 0;
- fSensSelect = 0;
- return;
- }
+ // The hit coordinates and charge
+ gMC->TrackPosition(pos);
+ hits[0] = pos[0];
+ hits[1] = pos[1];
+ hits[2] = pos[2];
- if ((nsector < 1) || (nsector > 18)) {
- printf("Wrong input value : %d\n",nsector);
- printf("Use standard setting\n");
- fSensSector = -1;
- fSensSectorRange = 0;
- fSensSelect = 0;
- return;
- }
+ // The sector number (0 - 17)
+ // The numbering goes clockwise and starts at y = 0
+ Float_t phi = kRaddeg*TMath::ATan2(pos[0],pos[1]);
+ if (phi < 90.0) {
+ phi = phi + 270.0;
+ }
+ else {
+ phi = phi - 90.0;
+ }
+ sec = ((Int_t) (phi / 20.0));
+
+ // The plane and chamber number
+ cIdChamber[0] = cIdCurrent[2];
+ cIdChamber[1] = cIdCurrent[3];
+ Int_t idChamber = (atoi(cIdChamber) % kNdetsec);
+ cha = kNcham - ((Int_t) idChamber / kNplan) - 1;
+ pla = ((Int_t) idChamber % kNplan);
+
+ // The detector number
+ det = fGeometry->GetDetector(pla,cha,sec);
+
+ // Special hits only in the drift region
+ if ((drRegion) &&
+ (gMC->IsTrackEntering())) {
+
+ // Create a track reference at the entrance of each
+ // chamber that contains the momentum components of the particle
+ gMC->TrackMomentum(mom);
+ AddTrackReference(gAlice->GetMCApp()->GetCurrentTrackNumber());
+
+ // Create the hits from TR photons if electron/positron is
+ // entering the drift volume
+ if ((fTR) &&
+ (TMath::Abs(gMC->TrackPid()) == kPdgElectron)) {
+ CreateTRhit(det);
+ }
+
+ }
+ else if ((amRegion) &&
+ (gMC->IsTrackExiting())) {
+
+ // Create a track reference at the exit of each
+ // chamber that contains the momentum components of the particle
+ gMC->TrackMomentum(mom);
+ AddTrackReference(gAlice->GetMCApp()->GetCurrentTrackNumber());
+
+ }
+
+ // Calculate the energy of the delta-electrons
+ // modified by Alex Bercuci (A.Bercuci@gsi.de) on 26.01.06
+ // take into account correlation with the underlying GEANT tracking
+ // mechanism. see
+ // http://www-linux.gsi.de/~abercuci/Contributions/TRD/index.html
+ //
+ // determine the most significant process (last on the processes list)
+ // which caused this hit
+ gMC->StepProcesses(processes);
+ Int_t nofprocesses = processes.GetSize();
+ Int_t pid;
+ if (!nofprocesses) {
+ pid = 0;
+ }
+ else {
+ pid = processes[nofprocesses-1];
+ }
+
+ // Generate Edep according to GEANT parametrisation
+ eDelta = TMath::Exp(fDeltaG->GetRandom()) - kPoti;
+ eDelta = TMath::Max(eDelta,0.0);
+ Float_t prRange = 0.0;
+ Float_t range = gMC->TrackLength() - fTrackLength0;
+ // merge GEANT tracker information with locally cooked one
+ if (gAlice->GetMCApp()->GetCurrentTrackNumber() == fPrimaryTrackPid) {
+ if (pid == 27) {
+ if (eDelta >= kECut) {
+ prRange = kRa * eDelta * 0.001
+ * (1.0 - kRb / (1.0 + kRc * eDelta * 0.001)) / kRho;
+ if (prRange >= (3.7 - range)) {
+ eDelta *= 0.1;
+ }
+ }
+ }
+ else if (pid == 1) {
+ if (eDelta < kECut) {
+ eDelta *= 0.5;
+ }
+ else {
+ prRange = kRa * eDelta * 0.001
+ * (1.0 - kRb / (1.0 + kRc * eDelta * 0.001)) / kRho;
+ if (prRange >= ((AliTRDgeometry::DrThick()
+ + AliTRDgeometry::AmThick()) - range)) {
+ eDelta *= 0.05;
+ }
+ else {
+ eDelta *= 0.5;
+ }
+ }
+ }
+ else {
+ eDelta = 0.0;
+ }
+ }
+ else {
+ eDelta = 0.0;
+ }
+
+ // Generate the electron cluster size
+ if (eDelta > 0.0) {
+
+ qTot = ((Int_t) (eDelta / kWion) + 1);
+
+ // Create a new dEdx hit
+ AddHit(gAlice->GetMCApp()->GetCurrentTrackNumber()
+ ,det
+ ,hits
+ ,qTot
+ ,drRegion);
+
+ }
+
+ // Calculate the maximum step size for the next tracking step
+ // Produce only one hit if Ekin is below cutoff
+ aMass = gMC->TrackMass();
+ if ((gMC->Etot() - aMass) > kEkinMinStep) {
+
+ // The energy loss according to Bethe Bloch
+ iPdg = TMath::Abs(gMC->TrackPid());
+ if ((iPdg != kPdgElectron) ||
+ ((iPdg == kPdgElectron) &&
+ (pTot < kPTotMaxEl))) {
+ gMC->TrackMomentum(mom);
+ pTot = mom.Rho();
+ betaGamma = pTot / aMass;
+ pp = BetheBlochGeant(betaGamma);
+ // Take charge > 1 into account
+ charge = gMC->TrackCharge();
+ if (TMath::Abs(charge) > 1) {
+ pp = pp * charge*charge;
+ }
+ }
+ else {
+ // Electrons above 20 Mev/c are at the plateau
+ pp = kPrim * kPlateau;
+ }
+
+ Int_t nsteps = 0;
+ do {
+ nsteps = gRandom->Poisson(pp);
+ } while(!nsteps);
+ stepSize = 1.0 / nsteps;
+ gMC->SetMaxStep(stepSize);
+
+ }
- fSensSelect = 1;
- fSensSector = isector;
- fSensSectorRange = nsector;
+ }
+
+ }
}
//_____________________________________________________________________________
-void AliTRDv1::StepManager()
+void AliTRDv1::StepManagerErmilova()
{
//
// Slow simulator. Every charged track produces electron cluster as hits
@@ -501,9 +652,6 @@ void AliTRDv1::StepManager()
// a spectrum taken from Ermilova et al.
//
- Int_t iIdSens, icSens;
- Int_t iIdSpace, icSpace;
- Int_t iIdChamber, icChamber;
Int_t pla = 0;
Int_t cha = 0;
Int_t sec = 0;
@@ -512,235 +660,186 @@ void AliTRDv1::StepManager()
Int_t qTot;
Float_t hits[3];
- Float_t random[1];
+ Double_t random[1];
Float_t charge;
Float_t aMass;
- Double_t pTot;
+ Double_t pTot = 0.0;
Double_t eDelta;
- Double_t betaGamma, pp;
+ Double_t betaGamma;
+ Double_t pp;
+ Double_t stepSize;
- TLorentzVector pos, mom;
- TClonesArray &lhits = *fHits;
+ Bool_t drRegion = kFALSE;
+ Bool_t amRegion = kFALSE;
- const Double_t kBig = 1.0E+12;
+ TString cIdCurrent;
+ TString cIdSensDr = "J";
+ TString cIdSensAm = "K";
+ Char_t cIdChamber[3];
+ cIdChamber[2] = 0;
+
+ TLorentzVector pos;
+ TLorentzVector mom;
+
+ const Int_t kNplan = AliTRDgeometry::Nplan();
+ const Int_t kNcham = AliTRDgeometry::Ncham();
+ const Int_t kNdetsec = kNplan * kNcham;
+
+ const Double_t kBig = 1.0e+12; // Infinitely big
+ const Float_t kWion = 23.53; // Ionization energy
+ const Float_t kPTotMaxEl = 0.002; // Maximum momentum for e+ e- g
+
+ // Minimum energy for the step size adjustment
+ const Float_t kEkinMinStep = 1.0e-5;
- // Ionization energy
- const Float_t kWion = 22.04;
- // Maximum energy for e+ e- g for the step-size calculation
- const Float_t kPTotMax = 0.002;
// Plateau value of the energy-loss for electron in xenon
- // taken from: Allison + Comb, Ann. Rev. Nucl. Sci. (1980), 30, 253
- //const Double_t kPlateau = 1.70;
- // the averaged value (26/3/99)
- const Float_t kPlateau = 1.55;
+ // The averaged value (26/3/99)
+ const Float_t kPlateau = 1.55;
// dN1/dx|min for the gas mixture (90% Xe + 10% CO2)
- const Float_t kPrim = 48.0;
+ const Float_t kPrim = 48.0;
// First ionization potential (eV) for the gas mixture (90% Xe + 10% CO2)
- const Float_t kPoti = 12.1;
-
+ const Float_t kPoti = 12.1;
// PDG code electron
- const Int_t kPdgElectron = 11;
+ const Int_t kPdgElectron = 11;
// Set the maximum step size to a very large number for all
// neutral particles and those outside the driftvolume
gMC->SetMaxStep(kBig);
- // Create some special hits with amplitude 0 at the entrance and
- // exit of each chamber that contain the momentum components of the particle
- if (gMC->TrackCharge() &&
- (gMC->IsTrackEntering() || gMC->IsTrackExiting())) {
+ // Use only charged tracks
+ if (( gMC->TrackCharge() ) &&
+ (!gMC->IsTrackDisappeared())) {
// Inside a sensitive volume?
- iIdSens = gMC->CurrentVolID(icSens);
- if (iIdSens == fIdSens) {
-
- iIdSpace = gMC->CurrentVolOffID(4,icSpace );
- iIdChamber = gMC->CurrentVolOffID(1,icChamber);
+ drRegion = kFALSE;
+ amRegion = kFALSE;
+ cIdCurrent = gMC->CurrentVolName();
+ if (cIdSensDr == cIdCurrent[1]) {
+ drRegion = kTRUE;
+ }
+ if (cIdSensAm == cIdCurrent[1]) {
+ amRegion = kTRUE;
+ }
+ if (drRegion || amRegion) {
- // The hit coordinates
+ // The hit coordinates and charge
gMC->TrackPosition(pos);
-
- // The track momentum
- gMC->TrackMomentum(mom);
- hits[0] = mom[0];
- hits[1] = mom[1];
- hits[2] = mom[2];
+ hits[0] = pos[0];
+ hits[1] = pos[1];
+ hits[2] = pos[2];
// The sector number (0 - 17)
// The numbering goes clockwise and starts at y = 0
Float_t phi = kRaddeg*TMath::ATan2(pos[0],pos[1]);
- if (phi < 90.)
- phi = phi + 270.;
- else
- phi = phi - 90.;
- sec = ((Int_t) (phi / 20));
-
- // The chamber number
- // 0: outer left
- // 1: middle left
- // 2: inner
- // 3: middle right
- // 4: outer right
- if (iIdChamber == fIdChamber1)
- cha = (hits[2] < 0 ? 0 : 4);
- else if (iIdChamber == fIdChamber2)
- cha = (hits[2] < 0 ? 1 : 3);
- else if (iIdChamber == fIdChamber3)
- cha = 2;
-
- // The plane number
- // The numbering starts at the innermost plane
- pla = icChamber - TMath::Nint((Float_t) (icChamber / 7)) * 6 - 1;
-
- // Check on selected volumes
- Int_t addthishit = 1;
- if (fSensSelect) {
- if ((fSensPlane >= 0) && (pla != fSensPlane )) addthishit = 0;
- if ((fSensChamber >= 0) && (cha != fSensChamber)) addthishit = 0;
- if (fSensSector >= 0) {
- Int_t sens1 = fSensSector;
- Int_t sens2 = fSensSector + fSensSectorRange;
- sens2 -= ((Int_t) (sens2 / AliTRDgeometry::Nsect()))
- * AliTRDgeometry::Nsect();
- if (sens1 < sens2) {
- if ((sec < sens1) || (sec >= sens2)) addthishit = 0;
- }
- else {
- if ((sec < sens1) && (sec >= sens2)) addthishit = 0;
- }
- }
+ if (phi < 90.0) {
+ phi = phi + 270.0;
}
-
- // Add this hit
- if (addthishit) {
- det = fGeometry->GetDetector(pla,cha,sec);
- new(lhits[fNhits++]) AliTRDhit(fIshunt
- ,gAlice->CurrentTrack()
- ,det
- ,hits
- ,0);
+ else {
+ phi = phi - 90.0;
}
+ sec = ((Int_t) (phi / 20.0));
- }
+ // The plane and chamber number
+ cIdChamber[0] = cIdCurrent[2];
+ cIdChamber[1] = cIdCurrent[3];
+ Int_t idChamber = (atoi(cIdChamber) % kNdetsec);
+ cha = kNcham - ((Int_t) idChamber / kNplan) - 1;
+ pla = ((Int_t) idChamber % kNplan);
- }
+ // The detector number
+ det = fGeometry->GetDetector(pla,cha,sec);
- // Use only charged tracks
- if (( gMC->TrackCharge() ) &&
- (!gMC->IsTrackStop() ) &&
- (!gMC->IsTrackDisappeared())) {
+ // Special hits only in the drift region
+ if ((drRegion) &&
+ (gMC->IsTrackEntering())) {
- // Inside a sensitive volume?
- iIdSens = gMC->CurrentVolID(icSens);
- if (iIdSens == fIdSens) {
+ // Create a track reference at the entrance of each
+ // chamber that contains the momentum components of the particle
+ gMC->TrackMomentum(mom);
+ AddTrackReference(gAlice->GetMCApp()->GetCurrentTrackNumber());
+
+ // Create the hits from TR photons if electron/positron is
+ // entering the drift volume
+ if ((fTR) &&
+ (TMath::Abs(gMC->TrackPid()) == kPdgElectron)) {
+ CreateTRhit(det);
+ }
- iIdSpace = gMC->CurrentVolOffID(4,icSpace );
- iIdChamber = gMC->CurrentVolOffID(1,icChamber);
+ }
+ else if ((amRegion) &&
+ (gMC->IsTrackExiting())) {
+
+ // Create a track reference at the exit of each
+ // chamber that contains the momentum components of the particle
+ gMC->TrackMomentum(mom);
+ AddTrackReference(gAlice->GetMCApp()->GetCurrentTrackNumber());
+
+ }
// Calculate the energy of the delta-electrons
eDelta = TMath::Exp(fDeltaE->GetRandom()) - kPoti;
eDelta = TMath::Max(eDelta,0.0);
- // The number of secondary electrons created
- qTot = ((Int_t) (eDelta / kWion) + 1);
+ // Generate the electron cluster size
+ if (eDelta > 0.0) {
- // The hit coordinates and charge
- gMC->TrackPosition(pos);
- hits[0] = pos[0];
- hits[1] = pos[1];
- hits[2] = pos[2];
+ qTot = ((Int_t) (eDelta / kWion) + 1);
- // The sector number (0 - 17)
- // The numbering goes clockwise and starts at y = 0
- Float_t phi = kRaddeg*TMath::ATan2(pos[0],pos[1]);
- if (phi < 90.)
- phi = phi + 270.;
- else
- phi = phi - 90.;
- sec = ((Int_t) (phi / 20));
-
- // The chamber number
- // 0: outer left
- // 1: middle left
- // 2: inner
- // 3: middle right
- // 4: outer right
- if (iIdChamber == fIdChamber1)
- cha = (hits[2] < 0 ? 0 : 4);
- else if (iIdChamber == fIdChamber2)
- cha = (hits[2] < 0 ? 1 : 3);
- else if (iIdChamber == fIdChamber3)
- cha = 2;
-
- // The plane number
- // The numbering starts at the innermost plane
- pla = icChamber - TMath::Nint((Float_t) (icChamber / 7)) * 6 - 1;
-
- // Check on selected volumes
- Int_t addthishit = 1;
- if (fSensSelect) {
- if ((fSensPlane >= 0) && (pla != fSensPlane )) addthishit = 0;
- if ((fSensChamber >= 0) && (cha != fSensChamber)) addthishit = 0;
- if (fSensSector >= 0) {
- Int_t sens1 = fSensSector;
- Int_t sens2 = fSensSector + fSensSectorRange;
- sens2 -= ((Int_t) (sens2 / AliTRDgeometry::Nsect()))
- * AliTRDgeometry::Nsect();
- if (sens1 < sens2) {
- if ((sec < sens1) || (sec >= sens2)) addthishit = 0;
- }
- else {
- if ((sec < sens1) && (sec >= sens2)) addthishit = 0;
- }
+ // Create a new dEdx hit
+ if (drRegion) {
+ AddHit(gAlice->GetMCApp()->GetCurrentTrackNumber()
+ ,det
+ ,hits
+ ,qTot
+ ,kTRUE);
+ }
+ else {
+ AddHit(gAlice->GetMCApp()->GetCurrentTrackNumber()
+ ,det
+ ,hits
+ ,qTot
+ ,kFALSE);
}
- }
-
- // Add this hit
- if (addthishit) {
-
- det = fGeometry->GetDetector(pla,cha,sec);
- // Create the electron cluster from TR photons
- if (fTR) CreateTRhit(det);
+ }
- new(lhits[fNhits++]) AliTRDhit(fIshunt
- ,gAlice->CurrentTrack()
- ,det
- ,hits
- ,qTot);
+ // Calculate the maximum step size for the next tracking step
+ // Produce only one hit if Ekin is below cutoff
+ aMass = gMC->TrackMass();
+ if ((gMC->Etot() - aMass) > kEkinMinStep) {
// The energy loss according to Bethe Bloch
- gMC->TrackMomentum(mom);
- pTot = mom.Rho();
- iPdg = TMath::Abs(gMC->TrackPid());
- if ( (iPdg != kPdgElectron) ||
- ((iPdg == kPdgElectron) && (pTot < kPTotMax))) {
- aMass = gMC->TrackMass();
+ iPdg = TMath::Abs(gMC->TrackPid());
+ if ((iPdg != kPdgElectron) ||
+ ((iPdg == kPdgElectron) &&
+ (pTot < kPTotMaxEl))) {
+ gMC->TrackMomentum(mom);
+ pTot = mom.Rho();
betaGamma = pTot / aMass;
pp = kPrim * BetheBloch(betaGamma);
- // Take charge > 1 into account
+ // Take charge > 1 into account
charge = gMC->TrackCharge();
- if (TMath::Abs(charge) > 1) pp = pp * charge*charge;
- }
- // Electrons above 20 Mev/c are at the plateau
- else {
- pp = kPrim * kPlateau;
+ if (TMath::Abs(charge) > 1) {
+ pp = pp * charge*charge;
+ }
+ }
+ else {
+ // Electrons above 20 Mev/c are at the plateau
+ pp = kPrim * kPlateau;
}
- // Calculate the maximum step size for the next tracking step
- if (pp > 0) {
- do
- gMC->Rndm(random,1);
- while ((random[0] == 1.) || (random[0] == 0.));
- gMC->SetMaxStep( - TMath::Log(random[0]) / pp);
- }
+ if (pp > 0.0) {
+ do {
+ gMC->GetRandom()->RndmArray(1,random);
+ }
+ while ((random[0] == 1.0) ||
+ (random[0] == 0.0));
+ stepSize = - TMath::Log(random[0]) / pp;
+ gMC->SetMaxStep(stepSize);
+ }
}
- else {
- // set step size to maximal value
- gMC->SetMaxStep(kBig);
- }
}
@@ -748,6 +847,154 @@ void AliTRDv1::StepManager()
}
+//_____________________________________________________________________________
+void AliTRDv1::StepManagerFixedStep()
+{
+ //
+ // Slow simulator. Every charged track produces electron cluster as hits
+ // along its path across the drift volume. The step size is fixed in
+ // this version of the step manager.
+ //
+
+ // PDG code electron
+ const Int_t kPdgElectron = 11;
+
+ Int_t pla = 0;
+ Int_t cha = 0;
+ Int_t sec = 0;
+ Int_t det = 0;
+ Int_t qTot;
+
+ Float_t hits[3];
+ Double_t eDep;
+
+ Bool_t drRegion = kFALSE;
+ Bool_t amRegion = kFALSE;
+
+ TString cIdCurrent;
+ TString cIdSensDr = "J";
+ TString cIdSensAm = "K";
+ Char_t cIdChamber[3];
+ cIdChamber[2] = 0;
+
+ TLorentzVector pos;
+ TLorentzVector mom;
+
+ const Int_t kNplan = AliTRDgeometry::Nplan();
+ const Int_t kNcham = AliTRDgeometry::Ncham();
+ const Int_t kNdetsec = kNplan * kNcham;
+
+ const Double_t kBig = 1.0e+12;
+
+ const Float_t kWion = 23.53; // Ionization energy
+ const Float_t kEkinMinStep = 1.0e-5; // Minimum energy for the step size adjustment
+
+ // Set the maximum step size to a very large number for all
+ // neutral particles and those outside the driftvolume
+ gMC->SetMaxStep(kBig);
+
+ // If not charged track or already stopped or disappeared, just return.
+ if ((!gMC->TrackCharge()) ||
+ gMC->IsTrackDisappeared()) {
+ return;
+ }
+
+ // Inside a sensitive volume?
+ cIdCurrent = gMC->CurrentVolName();
+
+ if (cIdSensDr == cIdCurrent[1]) {
+ drRegion = kTRUE;
+ }
+ if (cIdSensAm == cIdCurrent[1]) {
+ amRegion = kTRUE;
+ }
+
+ if ((!drRegion) &&
+ (!amRegion)) {
+ return;
+ }
+
+ // The hit coordinates and charge
+ gMC->TrackPosition(pos);
+ hits[0] = pos[0];
+ hits[1] = pos[1];
+ hits[2] = pos[2];
+
+ // The sector number (0 - 17)
+ // The numbering goes clockwise and starts at y = 0
+ Float_t phi = kRaddeg * TMath::ATan2(pos[0],pos[1]);
+ if (phi < 90.0) {
+ phi = phi + 270.0;
+ }
+ else {
+ phi = phi - 90.0;
+ }
+ sec = ((Int_t) (phi / 20.0));
+
+ // The plane and chamber number
+ cIdChamber[0] = cIdCurrent[2];
+ cIdChamber[1] = cIdCurrent[3];
+ Int_t idChamber = (atoi(cIdChamber) % kNdetsec);
+ cha = kNcham - ((Int_t) idChamber / kNplan) - 1;
+ pla = ((Int_t) idChamber % kNplan);
+
+ // The detector number
+ det = fGeometry->GetDetector(pla,cha,sec);
+
+ // 0: InFlight 1:Entering 2:Exiting
+ Int_t trkStat = 0;
+
+ // Special hits only in the drift region
+ if ((drRegion) &&
+ (gMC->IsTrackEntering())) {
+
+ // Create a track reference at the entrance of each
+ // chamber that contains the momentum components of the particle
+ gMC->TrackMomentum(mom);
+ AddTrackReference(gAlice->GetMCApp()->GetCurrentTrackNumber());
+ trkStat = 1;
+
+ // Create the hits from TR photons if electron/positron is
+ // entering the drift volume
+ if ((fTR) &&
+ (TMath::Abs(gMC->TrackPid()) == kPdgElectron)) {
+ CreateTRhit(det);
+ }
+
+ }
+ else if ((amRegion) &&
+ (gMC->IsTrackExiting())) {
+
+ // Create a track reference at the exit of each
+ // chamber that contains the momentum components of the particle
+ gMC->TrackMomentum(mom);
+ AddTrackReference(gAlice->GetMCApp()->GetCurrentTrackNumber());
+ trkStat = 2;
+
+ }
+
+ // Calculate the charge according to GEANT Edep
+ // Create a new dEdx hit
+ eDep = TMath::Max(gMC->Edep(),0.0) * 1.0e+09;
+ qTot = (Int_t) (eDep / kWion);
+ if ((qTot) ||
+ (trkStat)) {
+ AddHit(gAlice->GetMCApp()->GetCurrentTrackNumber()
+ ,det
+ ,hits
+ ,qTot
+ ,drRegion);
+ }
+
+ // Set Maximum Step Size
+ // Produce only one hit if Ekin is below cutoff
+ if ((gMC->Etot() - gMC->TrackMass()) < kEkinMinStep) {
+ return;
+ }
+ gMC->SetMaxStep(fStepSize);
+
+}
+
//_____________________________________________________________________________
Double_t AliTRDv1::BetheBloch(Double_t bg)
{
@@ -757,29 +1004,71 @@ Double_t AliTRDv1::BetheBloch(Double_t bg)
//
// This parameters have been adjusted to averaged values from GEANT
- const Double_t kP1 = 7.17960e-02;
- const Double_t kP2 = 8.54196;
- const Double_t kP3 = 1.38065e-06;
- const Double_t kP4 = 5.30972;
- const Double_t kP5 = 2.83798;
-
- // This parameters have been adjusted to Xe-data found in:
- // Allison & Cobb, Ann. Rev. Nucl. Sci. (1980), 30, 253
- //const Double_t kP1 = 0.76176E-1;
- //const Double_t kP2 = 10.632;
- //const Double_t kP3 = 3.17983E-6;
- //const Double_t kP4 = 1.8631;
- //const Double_t kP5 = 1.9479;
-
- if (bg > 0) {
- Double_t yy = bg / TMath::Sqrt(1. + bg*bg);
+ const Double_t kP1 = 7.17960e-02;
+ const Double_t kP2 = 8.54196;
+ const Double_t kP3 = 1.38065e-06;
+ const Double_t kP4 = 5.30972;
+ const Double_t kP5 = 2.83798;
+
+ // Lower cutoff of the Bethe-Bloch-curve to limit step sizes
+ const Double_t kBgMin = 0.8;
+ const Double_t kBBMax = 6.83298;
+
+ if (bg > kBgMin) {
+ Double_t yy = bg / TMath::Sqrt(1.0 + bg*bg);
Double_t aa = TMath::Power(yy,kP4);
- Double_t bb = TMath::Power((1./bg),kP5);
+ Double_t bb = TMath::Power((1.0/bg),kP5);
bb = TMath::Log(kP3 + bb);
- return ((kP2 - aa - bb)*kP1 / aa);
+ return ((kP2 - aa - bb) * kP1 / aa);
+ }
+ else {
+ return kBBMax;
+ }
+
+}
+
+//_____________________________________________________________________________
+Double_t AliTRDv1::BetheBlochGeant(Double_t bg)
+{
+ //
+ // Return dN/dx (number of primary collisions per centimeter)
+ // for given beta*gamma factor.
+ //
+ // Implemented by K.Oyama according to GEANT 3 parametrization shown in
+ // A.Andronic's webpage: http://www-alice.gsi.de/trd/papers/dedx/dedx.html
+ // This must be used as a set with IntSpecGeant.
+ //
+
+ Int_t i = 0;
+
+ Double_t arrG[20] = { 1.100000, 1.200000, 1.300000, 1.500000
+ , 1.800000, 2.000000, 2.500000, 3.000000
+ , 4.000000, 7.000000, 10.000000, 20.000000
+ , 40.000000, 70.000000, 100.000000, 300.000000
+ , 600.000000, 1000.000000, 3000.000000, 10000.000000 };
+
+ Double_t arrNC[20] = { 75.009056, 45.508083, 35.299252, 27.116327
+ , 22.734999, 21.411915, 19.934095, 19.449375
+ , 19.344431, 20.185553, 21.027925, 22.912676
+ , 24.933352, 26.504053, 27.387468, 29.566597
+ , 30.353779, 30.787134, 31.129285, 31.157350 };
+
+ // Betagamma to gamma
+ Double_t g = TMath::Sqrt(1.0 + bg*bg);
+
+ // Find the index just before the point we need.
+ for (i = 0; i < 18; i++) {
+ if ((arrG[i] < g) &&
+ (arrG[i+1] > g)) {
+ break;
+ }
}
- else
- return 0;
+
+ // Simple interpolation.
+ Double_t pp = ((arrNC[i+1] - arrNC[i]) / (arrG[i+1] - arrG[i]))
+ * (g - arrG[i]) + arrNC[i];
+
+ return pp;
}
@@ -795,37 +1084,41 @@ Double_t Ermilova(Double_t *x, Double_t *)
Double_t dpos;
Double_t dnde;
- Int_t pos1, pos2;
+ Int_t pos1;
+ Int_t pos2;
const Int_t kNv = 31;
- Float_t vxe[kNv] = { 2.3026, 2.9957, 3.4012, 3.6889, 3.9120
- , 4.0943, 4.2485, 4.3820, 4.4998, 4.6052
- , 4.7005, 5.0752, 5.2983, 5.7038, 5.9915
- , 6.2146, 6.5221, 6.9078, 7.3132, 7.6009
- , 8.0064, 8.5172, 8.6995, 8.9872, 9.2103
- , 9.4727, 9.9035,10.3735,10.5966,10.8198
- ,11.5129 };
-
- Float_t vye[kNv] = { 80.0 , 31.0 , 23.3 , 21.1 , 21.0
- , 20.9 , 20.8 , 20.0 , 16.0 , 11.0
- , 8.0 , 6.0 , 5.2 , 4.6 , 4.0
- , 3.5 , 3.0 , 1.4 , 0.67 , 0.44
- , 0.3 , 0.18 , 0.12 , 0.08 , 0.056
- , 0.04 , 0.023, 0.015, 0.011, 0.01
- , 0.004 };
+ Float_t vxe[kNv] = { 2.3026, 2.9957, 3.4012, 3.6889, 3.9120
+ , 4.0943, 4.2485, 4.3820, 4.4998, 4.6052
+ , 4.7005, 5.0752, 5.2983, 5.7038, 5.9915
+ , 6.2146, 6.5221, 6.9078, 7.3132, 7.6009
+ , 8.0064, 8.5172, 8.6995, 8.9872, 9.2103
+ , 9.4727, 9.9035, 10.3735, 10.5966, 10.8198
+ , 11.5129 };
+
+ Float_t vye[kNv] = { 80.0, 31.0, 23.3, 21.1, 21.0
+ , 20.9, 20.8, 20.0, 16.0, 11.0
+ , 8.0, 6.0, 5.2, 4.6, 4.0
+ , 3.5, 3.0, 1.4, 0.67, 0.44
+ , 0.3, 0.18, 0.12, 0.08, 0.056
+ , 0.04, 0.023, 0.015, 0.011, 0.01
+ , 0.004 };
energy = x[0];
// Find the position
- pos1 = pos2 = 0;
+ pos1 = 0;
+ pos2 = 0;
dpos = 0;
do {
dpos = energy - vxe[pos2++];
}
while (dpos > 0);
pos2--;
- if (pos2 > kNv) pos2 = kNv;
+ if (pos2 > kNv) {
+ pos2 = kNv - 1;
+ }
pos1 = pos2 - 1;
// Differentiate between the sampling points
@@ -834,3 +1127,72 @@ Double_t Ermilova(Double_t *x, Double_t *)
return dnde;
}
+
+//_____________________________________________________________________________
+Double_t IntSpecGeant(Double_t *x, Double_t *)
+{
+ //
+ // Integrated spectrum from Geant3
+ //
+
+ const Int_t npts = 83;
+ Double_t arre[npts] = { 2.421257, 2.483278, 2.534301, 2.592230
+ , 2.672067, 2.813299, 3.015059, 3.216819
+ , 3.418579, 3.620338, 3.868209, 3.920198
+ , 3.978284, 4.063923, 4.186264, 4.308605
+ , 4.430946, 4.553288, 4.724261, 4.837736
+ , 4.999842, 5.161949, 5.324056, 5.486163
+ , 5.679688, 5.752998, 5.857728, 5.962457
+ , 6.067185, 6.171914, 6.315653, 6.393674
+ , 6.471694, 6.539689, 6.597658, 6.655627
+ , 6.710957, 6.763648, 6.816338, 6.876198
+ , 6.943227, 7.010257, 7.106285, 7.252151
+ , 7.460531, 7.668911, 7.877290, 8.085670
+ , 8.302979, 8.353585, 8.413120, 8.483500
+ , 8.541030, 8.592857, 8.668865, 8.820485
+ , 9.037086, 9.253686, 9.470286, 9.686887
+ , 9.930838, 9.994655, 10.085822, 10.176990
+ , 10.268158, 10.359325, 10.503614, 10.627565
+ , 10.804637, 10.981709, 11.158781, 11.335854
+ , 11.593397, 11.781165, 12.049404, 12.317644
+ , 12.585884, 12.854123, 14.278421, 16.975889
+ , 20.829416, 24.682943, 28.536469 };
+
+ Double_t arrdnde[npts] = { 10.960000, 10.960000, 10.359500, 9.811340
+ , 9.1601500, 8.206670, 6.919630, 5.655430
+ , 4.6221300, 3.777610, 3.019560, 2.591950
+ , 2.5414600, 2.712920, 3.327460, 4.928240
+ , 7.6185300, 10.966700, 12.225800, 8.094750
+ , 3.3586900, 1.553650, 1.209600, 1.263840
+ , 1.3241100, 1.312140, 1.255130, 1.165770
+ , 1.0594500, 0.945450, 0.813231, 0.699837
+ , 0.6235580, 2.260990, 2.968350, 2.240320
+ , 1.7988300, 1.553300, 1.432070, 1.535520
+ , 1.4429900, 1.247990, 1.050750, 0.829549
+ , 0.5900280, 0.395897, 0.268741, 0.185320
+ , 0.1292120, 0.103545, 0.0949525, 0.101535
+ , 0.1276380, 0.134216, 0.123816, 0.104557
+ , 0.0751843, 0.0521745, 0.0373546, 0.0275391
+ , 0.0204713, 0.0169234, 0.0154552, 0.0139194
+ , 0.0125592, 0.0113638, 0.0107354, 0.0102137
+ , 0.00845984, 0.00683338, 0.00556836, 0.00456874
+ , 0.0036227, 0.00285991, 0.00226664, 0.00172234
+ , 0.00131226, 0.00100284, 0.000465492, 7.26607e-05
+ , 3.63304e-06, 0.0000000, 0.0000000 };
+
+ Int_t i;
+ Double_t energy = x[0];
+
+ for (i = 0; i < npts; i++) {
+ if (energy < arre[i]) {
+ break;
+ }
+ }
+
+ if (i == 0) {
+ AliErrorGeneral("AliTRDv1::IntSpecGeant","Given energy value is too small or zero");
+ }
+
+ return arrdnde[i];
+
+}