--- /dev/null
+/**************************************************************************
+ * 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. *
+ **************************************************************************/
+
+//-------------------------------------------------------------------------
+// Class AliRsnAnalysis
+// Reconstruction and analysis of a binary resonance
+//
+// author: A. Pulvirenti (email: alberto.pulvirenti@ct.infn.it)
+//-------------------------------------------------------------------------
+
+#include <Riostream.h>
+
+#include <TH1.h>
+#include <TTree.h>
+#include <TRefArray.h>
+#include <TParticle.h>
+#include <TObjectTable.h>
+#include <TDatabasePDG.h>
+
+#include "AliRsnDaughter.h"
+#include "AliRsnDaughterCut.h"
+#include "AliRsnEvent.h"
+#include "AliRsnAnalysis.h"
+
+ClassImp(AliRsnAnalysis)
+
+//--------------------------------------------------------------------------------------------------------
+AliRsnAnalysis::AliRsnAnalysis()
+//
+// Constructor
+// Initializes all pointers and collections to NULL.
+//
+{
+ fMixHistograms = 0;
+ fHistograms = 0;
+ fEventsTree = 0;
+ fMixPairDefs = 0;
+ fPairDefs = 0;
+ fPairCuts = 0;
+
+ Int_t i;
+ for (i = 0; i < AliPID::kSPECIES; i++) fCuts[i] = 0;
+}
+//--------------------------------------------------------------------------------------------------------
+void AliRsnAnalysis::AddCutPair(AliRsnDaughterCut *cut)
+//
+// Add a cut on pairs.
+// This cut is global for all pairs.
+//
+{
+ if (!cut->IsPairCut()) {
+ Warning("AddCutPair", "This is a single cut, cannot be added");
+ return;
+ }
+
+ if (!fPairCuts) fPairCuts = new TObjArray(0);
+
+ fPairCuts->AddLast(cut);
+}
+//--------------------------------------------------------------------------------------------------------
+void AliRsnAnalysis::AddCutSingle(AliPID::EParticleType type, AliRsnDaughterCut *cut)
+//
+// Add a cut on single particles.
+// This cut must be specified for each particle type.
+//
+{
+ if (cut->IsPairCut()) {
+ Warning("AddCutSingle", "This is a pair cut, cannot be added");
+ return;
+ }
+
+ if (type >= AliPID::kElectron && type <= AliPID::kProton) {
+ if (!fCuts[type]) fCuts[type] = new TObjArray(0);
+ fCuts[type]->AddLast(cut);
+ }
+}
+//--------------------------------------------------------------------------------------------------------
+void AliRsnAnalysis::AddMixPairDef
+(AliPID::EParticleType p1, Char_t sign1, AliPID::EParticleType p2, Char_t sign2)
+//
+// Adds a new pair definition to create a new histogram,
+// for the event mixing step.
+// If the pair defs array is NULL, it is initialized here.
+//
+{
+ if (!fMixPairDefs) fMixPairDefs = new TObjArray(0);
+ fMixPairDefs->AddLast( new AliPairDef(p1, sign1, p2, sign2, 0, kFALSE) );
+}
+//--------------------------------------------------------------------------------------------------------
+void AliRsnAnalysis::AddPairDef
+(AliPID::EParticleType p1, Char_t sign1, AliPID::EParticleType p2, Char_t sign2, Bool_t onlyTrue)
+//
+// Adds a new pair definition to create a new histogram,
+// for the signal evaluation (same event) step.
+// If the pair defs array is NULL, it is initialized here.
+//
+{
+ if (!fPairDefs) fPairDefs = new TObjArray(0);
+ fPairDefs->AddLast( new AliPairDef(p1, sign1, p2, sign2, fTrueMotherPDG, onlyTrue) );
+}
+//--------------------------------------------------------------------------------------------------------
+void AliRsnAnalysis::Clear(Option_t* /* option */)
+//
+// Clear heap
+//
+{
+ fHistograms->Clear("C");
+ fPairDefs->Clear("C");
+
+ fMixHistograms->Clear("C");
+ fMixPairDefs->Clear("C");
+
+ Int_t i;
+ for (i = 0; i < AliPID::kSPECIES; i++) fCuts[i]->Clear("C");
+ fPairCuts->Clear("C");
+}
+//--------------------------------------------------------------------------------------------------------
+Stat_t AliRsnAnalysis::EventMix(Int_t nmix, Int_t multDiffMax, Double_t vzDiffMax, Bool_t compareTotMult)
+//
+// Performs event mixing.
+// It takes the array of fMixPairDefs and stores results in fMixHistograms.
+// First parameter defines how many events must be mixed with each one.
+// Events to be mixed are chosen using the other parameters:
+//
+// - multDiffMax defines the maximum allowed difference in particle multiplicity,
+// a) when last argument is kFALSE (default) the multiplicity comparison is made with respect
+// to the particles of 'type 2' in the pair
+// b) when last argument is kTRUE, the multiplicity comparison is made with respect of total
+// particle multiplicity in the events
+//
+// - vzDiffMax defines maximum allowed difference in Z coordinate of prim. vertex.
+//
+// If one wants to exchange the particle types, one has to add both combinations of particles
+// as different pair defs.
+//
+// EXAMPLE:
+// analysis->AddMixPairDef(AliRsnEvent::kPion, '+', AliRsnEvent::kKaon, '-');
+// analysis->AddMixPairDef(AliRsnEvent::kKaon, '-', AliRsnEvent::kPion, '+');
+//
+{
+ // allocate the histograms array
+ Int_t i, npairdefs = (Int_t)fMixPairDefs->GetEntries();
+ fMixHistograms = new TObjArray(npairdefs);
+ TObjArray &histos = *fMixHistograms;
+ AliPairDef *pd = 0;
+ for (i = 0; i < npairdefs; i++) {
+ pd = (AliPairDef*)fMixPairDefs->At(i);
+ histos[i] = new TH1D(Form("hmix_%s", pd->GetName()), pd->GetTitle(), fNBins, fHistoMin, fHistoMax);
+ }
+
+ // Link events branch
+ AliRsnEvent *event2 = new AliRsnEvent;
+ fEventsTree->SetBranchAddress("events", &event2);
+
+ // define variables to store data about particles
+ Stat_t nPairs = 0;
+ Int_t iev, ievmix, nEvents = (Int_t)fEventsTree->GetEntries();
+
+ // loop on events
+ Int_t nmixed, mult1, mult2, diffMult;
+ Double_t vz1, vz2, diffVz;
+ for (iev = 0; iev < nEvents; iev++) {
+
+ // get event
+ event2->Clear("DELETE");
+ fEventsTree->GetEntry(iev);
+
+ // copy this event into 'event 1'
+ AliRsnEvent *event1 = new AliRsnEvent(*event2);
+
+ // get Z position of primary vertex
+ vz1 = event1->GetPrimaryVertexZ();
+
+ // if total multiplicities must be used
+ // it is computed here
+ if (compareTotMult) {
+ mult1 = event1->GetMultiplicity(kTRUE);
+ }
+ else {
+ mult1 = 0;
+ }
+
+ // message
+ if (iev % 10 == 0) cout << "\rMixing event " << iev << flush;
+
+ // loop on pair definitions
+ for (i = 0; i < npairdefs; i++) {
+
+ // get pair definition
+ pd = (AliPairDef*)fMixPairDefs->At(i);
+
+ // get histogram reference
+ TH1D *histogram = (TH1D*)histos[i];
+
+ // get multiplicity of particle type '2' in event '1'
+ if (!mult1) {
+ mult1 = (Int_t)event1->GetTracks(pd->GetSign2(), pd->GetParticle2())->GetEntries();
+ }
+
+ // loop on events for mixing
+ nmixed = 0;
+ ievmix = iev;
+ while (nmixed < nmix) {
+
+ // get other event (it starts from iev + 1, and
+ // loops again to 0 if reachs end of tree)
+ ievmix++;
+ if (ievmix >= nEvents) ievmix -= nEvents;
+
+ // if event-2-mix is equal to 'iev', then
+ // a complete loop has been done, and no more
+ // mixing can be done, even if they are too few
+ // then the loop breaks anyway
+ if (ievmix == iev) break;
+
+ // get other event
+ event2->Clear("DELETE");
+ fEventsTree->GetEntry(ievmix);
+
+ // get event stats related to event 2
+ vz2 = event2->GetPrimaryVertexZ();
+ if (compareTotMult) {
+ mult2 = event2->GetMultiplicity(kTRUE);
+ }
+ else {
+ mult2 = event2->GetTracks(pd->GetSign2(), pd->GetParticle2())->GetEntries();
+ }
+
+ // fill histogram if checks are passed
+ diffMult = TMath::Abs(mult1 - mult2);
+ diffVz = TMath::Abs(vz1 - vz2);
+ if (diffVz <= vzDiffMax && diffMult <= multDiffMax) {
+ //cout << ievmix << " " << flush;
+ nPairs += Compute(pd, histogram, event1, event2);
+ nmixed++;
+ }
+ }
+ }
+
+ event1->Clear("DELETE");
+ delete event1;
+ event1 = 0;
+
+ } // end loop on events
+ cout << endl;
+
+ return nPairs;
+}
+//--------------------------------------------------------------------------------------------------------
+Stat_t AliRsnAnalysis::Process()
+//
+// Reads the list 'fPairDefs', and builds an inv-mass histogram for each definition.
+// For each event, particle of 'type 1' are combined with particles of 'type 2' as
+// defined in each pair definition specified in the list, taking the list of both types
+// from the same event.
+// This method is supposed to evaluate the 'signal' of the resonance, containing the peak.
+// It can also be used when one wants to evaluate the 'background' with the 'wrong sign'
+// particle pairs.
+//
+{
+ // allocate the histograms array in order to contain
+ // as many objects as the number of pair definitionss
+ Int_t i, npairdefs = (Int_t)fPairDefs->GetEntries();
+ fHistograms = new TObjArray(npairdefs);
+ TObjArray &histos = *fHistograms;
+
+ // loop over pair defs in order to retrieve the particle species chosen
+ // which are used to set an unique name for the output histogram
+ // There will be a direct correspondence between the inder of pairdef in its array
+ // and the corresponding histogram in the 'fHistograms' list.
+ AliPairDef *pd = 0;
+ for (i = 0; i < npairdefs; i++) {
+ pd = (AliPairDef*)fPairDefs->At(i);
+ histos[i] = new TH1D(Form("h_%s", pd->GetName()), pd->GetTitle(), fNBins, fHistoMin, fHistoMax);
+ }
+
+ // Link events branch
+ AliRsnEvent *event = new AliRsnEvent;
+ fEventsTree->SetBranchAddress("events", &event);
+
+ // define variables to store data about particles
+ Stat_t nPairs = 0;
+ Int_t iev, nEvents = (Int_t)fEventsTree->GetEntries();
+
+ // loop on events
+ for (iev = 0; iev < nEvents; iev++) {
+
+ // get event
+ event->Clear("DELETE");
+ fEventsTree->GetEntry(iev);
+ if (iev % 1000 == 0) cout << "\rProcessing event " << iev << flush;
+
+ // loop over the collection of pair defs
+ for (i = 0; i < npairdefs; i++) {
+ pd = (AliPairDef*)fPairDefs->At(i);
+ TH1D *histogram = (TH1D*)histos[i];
+ // invoke AliPairDef method to fill histogram
+ nPairs += Compute(pd, histogram, event, event);
+ }
+
+ } // end loop on events
+ cout << endl;
+
+ return nPairs;
+}
+//--------------------------------------------------------------------------------------------------------
+void AliRsnAnalysis::WriteHistograms()
+//
+// Writes histograms in current directory
+//
+{
+ TH1D *histogram;
+ TObjArrayIter iter(fHistograms);
+ while ( (histogram = (TH1D*)iter.Next()) ) {
+ histogram->Write();
+ }
+
+ if (fMixHistograms) {
+ TObjArrayIter iterMix(fMixHistograms);
+ while ( (histogram = (TH1D*)iterMix.Next()) ) {
+ histogram->Write();
+ }
+ }
+}
+//--------------------------------------------------------------------------------------------------------
+Stat_t AliRsnAnalysis::Compute
+(AliPairDef *pd, TH1D* &histogram, AliRsnEvent *event1, AliRsnEvent *event2)
+//
+// Adds to the specified histogram the invariant mass spectrum calculated taking
+// particles of type 1 from event 1, and particles of type 2 from event 2.
+// Events can be equal (signal) or different (background with event mixing).
+//
+{
+ // define two 'cursor' objects
+ AliRsnDaughter *track1 = 0, *track2 = 0;
+
+ // define iterators for the two collections
+ if (!event1 || !event1->GetTracks(pd->GetSign1(), pd->GetParticle1())) {
+ Error("Compute", "Null pointer for particle 1 collection");
+ return 0.0;
+ }
+ if (!event2 || !event2->GetTracks(pd->GetSign2(), pd->GetParticle2())) {
+ Error("Compute", "Null pointer for particle 2 collection");
+ return 0.0;
+ }
+ TObjArrayIter iter1(event1->GetTracks(pd->GetSign1(), pd->GetParticle1()));
+ TObjArrayIter iter2(event2->GetTracks(pd->GetSign2(), pd->GetParticle2()));
+
+ // define temporary variables for better code readability
+ Stat_t nPairs = 0;
+
+ // loop on particle of type 1 (in event 1)
+ while ( (track1 = (AliRsnDaughter*)iter1.Next()) ) {
+
+ if (fRejectFakes && (track1->GetLabel() < 0)) continue;
+ if (!SingleCutCheck(pd->GetParticle1(), track1)) continue;
+
+ iter2.Reset();
+
+ // loop on particles of type 2 (in event 2)
+ while ( (track2 = (AliRsnDaughter*)iter2.Next()) ) {
+
+ if (fRejectFakes && (track2->GetLabel() < 0)) continue;
+ if (event1 == event2 && track1->GetIndex() == track2->GetIndex()) continue;
+ if (!SingleCutCheck(pd->GetParticle2(), track2)) continue;
+ if (!PairCutCheck(track1, track2)) continue;
+
+ /*
+ // check
+ Char_t sign1 = (track1->GetSign() > 0) ? '+' : '-';
+ Char_t sign2 = (track2->GetSign() > 0) ? '+' : '-';
+ Info("Compute", "Particle 1: PDG = %d, sign = %c --- Particle 2: PDG = %d, sign = %c", track1->GetTruePDG(), sign1, track2->GetTruePDG(), sign2);
+ */
+
+ // total 4-momentum
+ track1->SetMass(pd->GetMass1());
+ track2->SetMass(pd->GetMass2());
+ AliRsnDaughter sum = (*track1) + (*track2);
+
+ // if the choice to get ONLY true pairs is selected, a check is made on the mothers
+ if (pd->GetOnlyTrue()) {
+ // the 'sum' AliRsnDaughter object is initialized with
+ // the PDG code of the common mother (if it is the case)
+ if (TMath::Abs(sum.GetMotherPDG()) == TMath::Abs(fTrueMotherPDG)) {
+ histogram->Fill(sum.GetMass());
+ nPairs++;
+ }
+ }
+ else {
+ histogram->Fill(sum.GetMass());
+ nPairs++;
+ }
+
+ } // end loop 2
+
+ } // end loop 1
+
+ return nPairs;
+}
+//--------------------------------------------------------------------------------------------------------
+Bool_t AliRsnAnalysis::SingleCutCheck(Int_t itype, AliRsnDaughter *track)
+//
+// Checks a track against single particle cuts (if defined)
+//
+{
+ if (!fCuts[itype]) return kTRUE;
+
+ TObjArrayIter iter(fCuts[itype]);
+ AliRsnDaughterCut *cut = 0;
+ while ( (cut = (AliRsnDaughterCut*)iter.Next()) ) {
+ if (!cut->Pass(track)) return kFALSE;
+ }
+
+ return kTRUE;
+}
+//--------------------------------------------------------------------------------------------------------
+Bool_t AliRsnAnalysis::PairCutCheck(AliRsnDaughter *track1, AliRsnDaughter *track2)
+//
+// Checks a pair against pair cuts (if defined)
+//
+{
+ if (!fPairCuts) return kTRUE;
+
+ TObjArrayIter iter(fPairCuts);
+ AliRsnDaughterCut *cut = 0;
+ while ( (cut = (AliRsnDaughterCut*)iter.Next()) ) {
+ if (!cut->Pass(track1, track2)) return kFALSE;
+ }
+
+ return kTRUE;
+}
+//--------------------------------------------------------------------------------------------------------
+AliRsnAnalysis::AliPairDef::AliPairDef
+(AliPID::EParticleType p1, Char_t sign1,
+ AliPID::EParticleType p2, Char_t sign2, Int_t pdgMother, Bool_t onlyTrue)
+//
+// Constructor for nested class
+//
+{
+ fOnlyTrue = onlyTrue;
+ fTrueMotherPDG = 0;
+ if (fOnlyTrue) fTrueMotherPDG = pdgMother;
+
+ fSign1 = sign1;
+ fParticle1 = p1;
+
+ fSign2 = sign2;
+ fParticle2 = p2;
+
+ // instance a PDG database to recovery true masses of particles
+ TDatabasePDG *db = TDatabasePDG::Instance();
+ Int_t pdg1 = AliPID::ParticleCode((Int_t)p1);
+ Int_t pdg2 = AliPID::ParticleCode((Int_t)p2);
+ fMass1 = db->GetParticle(pdg1)->Mass();
+ fMass2 = db->GetParticle(pdg2)->Mass();
+
+ // set name according to the chosen particles
+ fName.Append(Form("%s(%c)_%s(%c)", ParticleName(p1), sign1, ParticleName(p2), sign2));
+ fTitle.Append(Form("Inv. mass for %s(%c) and %s(%c)", ParticleName(p1), sign1, ParticleName(p2), sign2));
+ if (onlyTrue) {
+ fName.Append("_true");
+ fTitle.Append(" (true pairs)");
+ }
+}
+//--------------------------------------------------------------------------------------------------------
+Text_t* AliRsnAnalysis::AliPairDef::ParticleName(AliPID::EParticleType part)
+//
+// [PRIVATE]
+// Returns the name of the particle in text format
+//
+{
+ if (part == AliPID::kElectron) return ("E");
+ else if (part == AliPID::kMuon) return ("Mu");
+ else if (part == AliPID::kPion) return ("Pi");
+ else if (part == AliPID::kKaon) return ("K");
+ else if (part == AliPID::kProton) return ("P");
+ else {
+ Warning("ParticleName", "Unrecognized value of EParticle argument");
+ return ("???");
+ }
+}
+//--------------------------------------------------------------------------------------------------------
--- /dev/null
+/**************************************************************************
+ * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
+ * See cxx source for full Copyright notice *
+ **************************************************************************/
+
+//-------------------------------------------------------------------------
+// Class AliRsnAnalysis
+// Reconstruction and analysis of K* Rsn
+//
+// author: A. Pulvirenti (email: alberto.pulvirenti@ct.infn.it)
+//-------------------------------------------------------------------------
+
+#ifndef AliRsnANALYSIS_H
+#define AliRsnANALYSIS_H
+
+#include <TNamed.h>
+
+#include "AliPID.h"
+
+class TH1D;
+class TObjArray;
+class AliRsnEvent;
+class AliRsnDaughter;
+class AliRsnDaughterCut;
+
+class AliRsnAnalysis : public TObject
+{
+public:
+
+ AliRsnAnalysis();
+ virtual ~AliRsnAnalysis() {Clear();}
+
+ void AddCutPair(AliRsnDaughterCut *cut);
+ void AddCutSingle(AliPID::EParticleType type, AliRsnDaughterCut *cut);
+ void AddMixPairDef(AliPID::EParticleType p1, Char_t s1, AliPID::EParticleType p2, Char_t s2);
+ void AddPairDef(AliPID::EParticleType p1, Char_t s1, AliPID::EParticleType p2, Char_t s2, Bool_t onlyTrue = kFALSE);
+ void Clear(Option_t *option = "");
+ Stat_t EventMix(Int_t nmix = 5, Int_t multDiffMax = 10, Double_t vzDiffMax = 0.01, Bool_t compareTotalMult = kFALSE);
+ Stat_t Process();
+ void SetBins(Int_t nbins, Double_t min, Double_t max) {fNBins=nbins;fHistoMin=min;fHistoMax=max;}
+ void SetEventsTree(TTree *tree) {fEventsTree = tree;}
+ void SetRejectFakes(Bool_t doit=kTRUE) {fRejectFakes = doit;}
+ void SetTrueMotherPDG(Int_t pdg) {fTrueMotherPDG = pdg;}
+ void WriteHistograms();
+
+private:
+
+ class AliPairDef : public TNamed
+ {
+ public:
+
+ AliPairDef(AliPID::EParticleType p1, Char_t s1, AliPID::EParticleType p2, Char_t s2, Int_t pdg, Bool_t onlyTrue = kFALSE);
+
+ virtual ~AliPairDef() { }
+
+ Char_t GetSign1() {return fSign1;}
+ Char_t GetSign2() {return fSign2;}
+ Bool_t GetOnlyTrue() {return fOnlyTrue;}
+ AliPID::EParticleType GetParticle1() {return fParticle1;}
+ AliPID::EParticleType GetParticle2() {return fParticle2;}
+ Double_t GetMass1() {return fMass1;}
+ Double_t GetMass2() {return fMass2;}
+
+ void SetSign1(Char_t value) {fSign1 = value;}
+ void SetSign2(Char_t value) {fSign2 = value;}
+ void SetOnlyTrue(Bool_t value = kTRUE) {fOnlyTrue = value;}
+ void SetTrueMotherPDG(Int_t pdg) {fTrueMotherPDG = pdg;}
+ void SetParticle1(AliPID::EParticleType p) {fParticle1 = p;}
+ void SetParticle2(AliPID::EParticleType p) {fParticle2 = p;}
+
+ Text_t* ParticleName(AliPID::EParticleType part);
+
+ private:
+
+ Bool_t fOnlyTrue; // flag to be used for spectra of true pairs
+ Int_t fTrueMotherPDG; // PDG code of true mother (if requested)
+
+ Double_t fMass1; //
+ Char_t fSign1; // info about particle 1
+ AliPID::EParticleType fParticle1; //
+
+ Double_t fMass2; //
+ Char_t fSign2; // info about particle 2
+ AliPID::EParticleType fParticle2; //
+ };
+
+ Stat_t Compute(AliPairDef *pd, TH1D* &h, AliRsnEvent *ev1, AliRsnEvent *ev2);
+ Bool_t SingleCutCheck(Int_t itype, AliRsnDaughter *track);
+ Bool_t PairCutCheck(AliRsnDaughter *track1, AliRsnDaughter *track2);
+
+ Bool_t fRejectFakes; // reject particles labeled as fake
+
+ Int_t fNBins; // number of histogram bins
+ Double_t fHistoMin; // minimum of the histograms
+ Double_t fHistoMax; // maximum of the histograms
+
+ Int_t fTrueMotherPDG; // PDG code of true mother (used to create 'true' histos)
+
+ TObjArray *fMixPairDefs; // list of pair definitions for histograms (event mixing)
+ TObjArray *fMixHistograms; //! list of invmass histograms created (event mixing)
+
+ TObjArray *fPairDefs; // list of pair definitions for histograms
+ TObjArray *fHistograms; //! list of invmass histograms created
+
+ TObjArray *fCuts[AliPID::kSPECIES]; //! list of single particle cuts for each particle type
+ TObjArray *fPairCuts; //! list of pair cuts
+ TTree *fEventsTree; //! TTree of events (can not be created here, must be passed)
+
+ // Rsn analysis implementation
+ ClassDef(AliRsnAnalysis,1)
+};
+
+#endif
git://git.uio.no / u / mrichter / AliRoot.git / commitdiff