// Implementation of the TRD PID class //
// //
// Assigns the electron and pion likelihoods to each ESD track. //
-// The function MakePID(AliESD *event) calculates the probability //
+// The function MakePID(AliESDEvent *event) calculates the probability //
// of having dedx and a maximum timbin at a given //
// momentum (mom) and particle type k //
// from the precalculated distributions. //
// //
// Authors : //
-// Prashant Shukla <shukla@pi0.physi.uni-heidelberg.de> (Original version)//
-// Alex Bercuci (a.bercuci@gsi.de) //
+// Prashant Shukla <shukla@pi0.physi.uni-heidelberg.de> (orig. version) //
+// Alex Bercuci (a.bercuci@gsi.de) //
// //
////////////////////////////////////////////////////////////////////////////
#include "AliLog.h"
-#include "AliESD.h"
+#include "AliESDEvent.h"
#include "AliESDtrack.h"
+#include "AliTracker.h"
+#include "AliRun.h"
+#include "AliTRDReconstructor.h"
#include "AliTRDpidESD.h"
#include "AliTRDgeometry.h"
#include "AliTRDcalibDB.h"
-#include "AliRun.h"
#include "AliTRDtrack.h"
-#include "Cal/AliTRDCalPIDLQ.h"
+#include "Cal/AliTRDCalPID.h"
ClassImp(AliTRDpidESD)
- Bool_t AliTRDpidESD::fCheckTrackStatus = kTRUE;
- Bool_t AliTRDpidESD::fCheckKinkStatus = kFALSE;
- Int_t AliTRDpidESD::fMinPlane = 0;
+Bool_t AliTRDpidESD::fgCheckTrackStatus = kTRUE;
+Bool_t AliTRDpidESD::fgCheckKinkStatus = kFALSE;
+Int_t AliTRDpidESD::fgMinPlane = 0;
//_____________________________________________________________________________
AliTRDpidESD::AliTRDpidESD()
:TObject()
+ ,fTrack(0x0)
{
//
// Default constructor
//_____________________________________________________________________________
AliTRDpidESD::AliTRDpidESD(const AliTRDpidESD &p)
:TObject(p)
+ ,fTrack(0x0)
{
//
// AliTRDpidESD copy constructor
}
+//_____________________________________________________________________________
+AliTRDpidESD::~AliTRDpidESD()
+{
+ //
+ // Destructor
+ //
+
+ if(fTrack) delete fTrack;
+
+}
+
//_____________________________________________________________________________
AliTRDpidESD &AliTRDpidESD::operator=(const AliTRDpidESD &p)
{
// Copy function
//
- ((AliTRDpidESD &) p).fCheckTrackStatus = fCheckTrackStatus;
- ((AliTRDpidESD &) p).fCheckKinkStatus = fCheckKinkStatus;
- ((AliTRDpidESD &) p).fMinPlane = fMinPlane;
-
+ ((AliTRDpidESD &) p).fgCheckTrackStatus = fgCheckTrackStatus;
+ ((AliTRDpidESD &) p).fgCheckKinkStatus = fgCheckKinkStatus;
+ ((AliTRDpidESD &) p).fgMinPlane = fgMinPlane;
+ ((AliTRDpidESD &) p).fTrack = 0x0;
+
}
//_____________________________________________________________________________
-Int_t AliTRDpidESD::MakePID(AliESD *event)
+Int_t AliTRDpidESD::MakePID(AliESDEvent *event)
{
//
// This function calculates the PID probabilities based on TRD signals
// The method produces probabilities based on the charge
// and the position of the maximum time bin in each layer.
// The dE/dx information can be used as global charge or 2 to 3
- // slices. Check AliTRDCalPIDLQ and AliTRDCalPIDLQRef for the actual
+ // slices. Check AliTRDCalPID and AliTRDCalPIDRefMaker for the actual
// implementation.
//
// Author
// Alex Bercuci (A.Bercuci@gsi.de) 2nd May 2007
+ //
AliTRDcalibDB *calibration = AliTRDcalibDB::Instance();
if (!calibration) {
return -1;
}
+ AliTRDrecoParam *rec = AliTRDReconstructor::RecoParam();
+ if (!rec) {
+ AliErrorGeneral("AliTRDpidESD::MakePID()", "No TRD reco param.");
+ return 0x0;
+ }
+
// Retrieve the CDB container class with the probability distributions
- const AliTRDCalPIDLQ *pd = calibration->GetPIDLQObject();
+ const AliTRDCalPID *pd = calibration->GetPIDObject(rec->GetPIDMethod());
if (!pd) {
AliErrorGeneral("AliTRDpidESD::MakePID()"
- ,"No access to AliTRDCalPIDLQ");
+ ,"No access to AliTRDCalPID");
return -1;
}
-
// Loop through all ESD tracks
Double_t p[10];
AliESDtrack *t = 0x0;
- Double_t dedx[AliTRDtrack::kNslice], dEdx;
- Int_t timebin;
- Float_t mom, length, probTotal;
- Int_t nPlanePID;
+ Float_t dedx[AliTRDtrack::kNslice], dEdx;
+ Int_t timebin;
+ Float_t mom, length;
+ Int_t nPlanePID;
for (Int_t i=0; i<event->GetNumberOfTracks(); i++) {
t = event->GetTrack(i);
-
+
// Check track
if(!CheckTrack(t)) continue;
+
// Skip tracks which have no TRD signal at all
if (t->GetTRDsignal() == 0.) continue;
// Loop over detector layers
- mom = 0.; //t->GetP();
- length = 0.;
- probTotal = 0.;
+ mom = 0.;
+ length = 0.;
nPlanePID = 0;
- for (Int_t iSpecies = 0; iSpecies < AliPID::kSPECIES; iSpecies++) p[iSpecies] = 1.;
- for (Int_t iPlan = 0; iPlan < AliTRDgeometry::kNplan; iPlan++) {
+ for (Int_t iSpecies = 0; iSpecies < AliPID::kSPECIES; iSpecies++)
+ p[iSpecies] = 1./AliPID::kSPECIES;
+
+ for (Int_t iLayer = 0; iLayer < AliTRDgeometry::kNlayer; iLayer++) {
// read data for track segment
for(int iSlice=0; iSlice<AliTRDtrack::kNslice; iSlice++)
- dedx[iSlice] = t->GetTRDsignals(iPlan, iSlice);
- dEdx = t->GetTRDsignals(iPlan, -1);
- timebin = t->GetTRDTimBin(iPlan);
+ dedx[iSlice] = t->GetTRDslice(iLayer, iSlice);
+ dEdx = t->GetTRDslice(iLayer, -1);
+ timebin = t->GetTRDTimBin(iLayer);
// check data
if ((dEdx <= 0.) || (timebin <= -1.)) continue;
// retrive kinematic info for this track segment
- if(!GetTrackSegmentKine(t, iPlan, mom, length)) continue;
+ if(!RecalculateTrackSegmentKine(t, iLayer, mom, length)){
+ // information is not fully reliable especialy for length
+ // estimation. To be used in the future.
+ }
// this track segment has fulfilled all requierments
nPlanePID++;
-
+
// Get the probabilities for the different particle species
for (Int_t iSpecies = 0; iSpecies < AliPID::kSPECIES; iSpecies++) {
- p[iSpecies] *= pd->GetProbability(iSpecies, mom, dedx, length);
- p[iSpecies] *= pd->GetProbabilityT(iSpecies, mom, timebin);
- probTotal += p[iSpecies];
+ p[iSpecies] *= pd->GetProbability(iSpecies, mom, dedx, length, iLayer);
+ //p[iSpecies] *= pd->GetProbabilityT(iSpecies, mom, timebin);
}
}
-
+ if(nPlanePID == 0) continue;
+
// normalize probabilities
- if(probTotal > 0.)
- for (Int_t iSpecies = 0; iSpecies < AliPID::kSPECIES; iSpecies++)
- if(nPlanePID > fMinPlane) p[iSpecies] /= probTotal;
- else p[iSpecies] = 1.0;
-
+ Double_t probTotal = 0.;
+ for (Int_t iSpecies = 0; iSpecies < AliPID::kSPECIES; iSpecies++) probTotal += p[iSpecies];
+ if(probTotal <= 0.){
+ AliWarning(Form("The total probability (%e) over all species <= 0 in ESD track %d."
+ , probTotal, i));
+ AliWarning("This may be caused by some error in reference data.");
+ AliWarning("Calculation continues but results might be corrupted.");
+ continue;
+ }
+ for(Int_t iSpecies = 0; iSpecies < AliPID::kSPECIES; iSpecies++) p[iSpecies] /= probTotal;
// book PID to the track
t->SetTRDpid(p);
+ t->SetTRDpidQuality(nPlanePID);
}
return 0;
+
}
//_____________________________________________________________________________
//
// Check the ESD track status
- if (fCheckTrackStatus) {
+ if (fgCheckTrackStatus) {
if (((t->GetStatus() & AliESDtrack::kTRDout ) == 0) &&
((t->GetStatus() & AliESDtrack::kTRDrefit) == 0)) return kFALSE;
}
// Check for ESD kink tracks
- if (fCheckKinkStatus && (t->GetKinkIndex(0) != 0)) return kFALSE;
+ if (fgCheckKinkStatus && (t->GetKinkIndex(0) != 0)) return kFALSE;
return kTRUE;
+
}
//_____________________________________________________________________________
-Bool_t AliTRDpidESD::GetTrackSegmentKine(AliESDtrack *t, Int_t plan, Float_t &mom, Float_t &length)
+Bool_t AliTRDpidESD::RecalculateTrackSegmentKine(AliESDtrack *esd
+ , Int_t layer
+ , Float_t &mom
+ , Float_t &length)
{
//
// Retrive momentum "mom" and track "length" in TRD chamber from plane
// "plan" according to information stored in AliESDtrack "t".
- //
+ //
+ // Origin
+ // Alex Bercuci (A.Bercuci@gsi.de)
+ //
- if(!gAlice){
- AliErrorGeneral("AliTRDpidESD::GetTrackSegmentKine()"
- ,"No gAlice object to retrive TRDgeometry and Magnetic fied - this has to be removed in the future.");
- return kFALSE;
- }
-
- // Retrieve TRD geometry -> Maybe there is a better way to do this
- Bool_t kSelfGeom = kFALSE;
- AliTRDgeometry *TRDgeom =0x0;
- if(gAlice) TRDgeom = AliTRDgeometry::GetGeometry(gAlice->GetRunLoader());
- if(!TRDgeom){
- AliWarningGeneral("AliTRDpidESD::GetTrackSegmentKine()", "Cannot load TRD geometry from gAlice! Build a new one.\n");
- TRDgeom = new AliTRDgeometry();
- kSelfGeom = kTRUE;
- }
const Float_t kAmHalfWidth = AliTRDgeometry::AmThick() / 2.;
- const Float_t kDrWidth = AliTRDgeometry::DrThick();
-
-
- // retrive the magnetic field
- Double_t xyz0[3] = { 0., 0., 0.}, xyz1[3];
- Double_t b[3], alpha;
- gAlice->Field(xyz0,b); // b[] is in kilo Gauss
- Float_t field = b[2] * 0.1; // Tesla
+ const Float_t kDrWidth = AliTRDgeometry::DrThick();
+ const Float_t kTime0 = AliTRDgeometry::GetTime0(layer);
+ // set initial length value to chamber height
+ length = 2 * kAmHalfWidth + kDrWidth;
- // find momentum at chamber entrance and track length in chamber
- AliExternalTrackParam *param = (plan<3) ? new AliExternalTrackParam(*t->GetInnerParam()) : new AliExternalTrackParam(*t->GetOuterParam());
-
- param->PropagateTo(TRDgeom->GetTime0(plan)+kAmHalfWidth, field);
- param->GetXYZ(xyz0);
- alpha = param->GetAlpha();
- param->PropagateTo(TRDgeom->GetTime0(plan)-kAmHalfWidth-kDrWidth, field);
- // eliminate track segments which are crossing SM boundaries along chamber
- if(TMath::Abs(alpha-param->GetAlpha())>.01){
- delete param;
- if(kSelfGeom) delete TRDgeom;
+ // retrive track's outer param
+ const AliExternalTrackParam *op = esd->GetOuterParam();
+ if(!op){
+ mom = esd->GetP();
return kFALSE;
}
- param->GetXYZ(xyz1);
- length = sqrt(
- (xyz1[0]-xyz0[0])*(xyz1[0]-xyz0[0])+
- (xyz1[1]-xyz0[1])*(xyz1[1]-xyz0[1])+
- (xyz1[2]-xyz0[2])*(xyz1[2]-xyz0[2])
- );
- param->GetPxPyPz(xyz1);
- mom = sqrt(xyz1[0]*xyz1[0] + xyz1[1]*xyz1[1] + xyz1[2]*xyz1[2]);
- delete param;
- if(kSelfGeom) delete TRDgeom;
+ AliExternalTrackParam *param = 0x0;
+ if(!fTrack){
+ fTrack = new AliExternalTrackParam(*op);
+ param = fTrack;
+ } else param = new(fTrack) AliExternalTrackParam(*op);
+
+ // retrive the magnetic field
+ Double_t xyz0[3];
+ op->GetXYZ(xyz0);
+ Float_t field = AliTracker::GetBz(xyz0); // Bz in kG at point xyz0
+ Double_t s, t;
+
+ // propagate to chamber entrance
+ if(!param->PropagateTo(kTime0-kAmHalfWidth-kDrWidth, field)){
+ mom = op->GetP();
+ s = op->GetSnp();
+ t = op->GetTgl();
+ if (s < 1.) length /= TMath::Sqrt((1. - s*s) / (1. + t*t));
+ return kFALSE;
+ }
+ mom = param->GetP();
+ s = param->GetSnp();
+ t = param->GetTgl();
+ if (s < 1.) length /= TMath::Sqrt((1. - s*s) / (1. + t*t));
+
+ // check if track is crossing tracking sector by propagating to chamber exit- maybe is too much :)
+ Double_t alpha = param->GetAlpha();
+ if(!param->PropagateTo(kTime0+kAmHalfWidth, field)) return kFALSE;
+
+ // mark track segments which are crossing SM boundaries along chamber
+ if(TMath::Abs(alpha-param->GetAlpha())>.01) return kFALSE;
+
return kTRUE;
-}
+}
git://git.uio.no / u / mrichter / AliRoot.git / blobdiff