In AliMUONPairLight, AliMUONTrackLight:
[u/mrichter/AliRoot.git] / MUON / AliMUONPairLight.cxx
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55fd51b0 1/**************************************************************************
2 * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
3 * SigmaEffect_thetadegrees *
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 purpeateose. It is *
13 * provided "as is" without express or implied warranty. *
14 **************************************************************************/
15
16/* $Id$ */
17
3d1463c8 18//-----------------------------------------------------------------------------
55fd51b0 19//This class was prepared by INFN Cagliari, July 2006
20//(authors: H.Woehri, A.de Falco)
21//
22// Compact information for the generated muon pairs in the MUON arm
23// useful at the last stage of the analysis chain
24// Pairs are built with two AliMUONTrackLight objects
25// Using the class AliMUONTrackLight this class combines the decay
26// information ("history") of the reconstructed tracks and fills
27// a series of flags for the formed reconstructed dimuon:
28// fIsCorrelated, fCreationProcess, fIsFeedDown, ...
29// for information about the dimuon, use PrintInfo with the appropriate
30// printflag
31// To be used together with AliMUONTrackLight
3d1463c8 32//-----------------------------------------------------------------------------
55fd51b0 33
34
35//MUON classes
36#include "AliMUONPairLight.h"
37//Root classes
38#include "TString.h"
39
40ClassImp(AliMUONPairLight)
41
42//====================================
43AliMUONPairLight::AliMUONPairLight() :
44 TObject(),
45 fMu0(),
46 fMu1(),
47 fCreationProcess(-999),
48 fIsCorrelated(kFALSE),
49 fCauseOfCorrelation (-1),
50 fIsFeedDown(kFALSE)
51{
52 /// default constructor
53 ;
54}
55
56//====================================
57
58AliMUONPairLight::AliMUONPairLight(AliMUONPairLight &dimuCopy)
59 : TObject(dimuCopy),
60 fMu0(dimuCopy.fMu0),
0060b2f7 61 fMu1(dimuCopy.fMu1),
55fd51b0 62 fCreationProcess(dimuCopy.fCreationProcess),
63 fIsCorrelated(dimuCopy.fIsCorrelated),
64 fCauseOfCorrelation (dimuCopy.fCauseOfCorrelation),
65 fIsFeedDown(dimuCopy.fIsFeedDown)
66{
67/// copy constructor
68/// fMu0 = AliMUONTrackLight(dimuCopy.fMu0);
69/// fMu1 = AliMUONTrackLight(dimuCopy.fMu1);
70/// fIsCorrelated = dimuCopy.fIsCorrelated;
71/// fCauseOfCorrelation = dimuCopy.fCauseOfCorrelation;
72/// fCreationProcess = dimuCopy.fCreationProcess;
73/// fIsFeedDown = dimuCopy.fIsFeedDown;
74 ;
75}
76
77//====================================
78
79AliMUONPairLight::~AliMUONPairLight(){
80 /// destructor
81}
82
83//====================================
84
e733e3dd 85AliMUONPairLight& AliMUONPairLight::operator=(const AliMUONPairLight& dimuCopy)
86{
87 // check assignment to self
88 if (this == &dimuCopy) return *this;
89
90 // base class assignment
91 TObject::operator=(dimuCopy);
92
93 // assignment operator
94 fMu0 = dimuCopy.fMu0;
95 fMu1 = dimuCopy.fMu1;
96 fCreationProcess = dimuCopy.fCreationProcess;
97 fIsCorrelated = dimuCopy.fIsCorrelated;
98 fCauseOfCorrelation = dimuCopy.fCauseOfCorrelation;
99 fIsFeedDown = dimuCopy.fIsFeedDown;
100}
101
102//====================================
103
55fd51b0 104Bool_t AliMUONPairLight::IsAResonance(){
105 /// checks if muon pair comes from a resonance decay
106 if (!fIsCorrelated) return kFALSE; //if muons not correlated, cannot be a resonance
107 //if muons are correlated, check if the PDG of the
108 //common mother is a resonance
b88403f3 109 Int_t nparents0 = fMu0.GetNParents();
110 Int_t nparents1 = fMu1.GetNParents();
55fd51b0 111
b88403f3 112 Int_t minP = TMath::Min(nparents0, nparents1);
113 for (Int_t i = 0 ; i < minP; i++) {
114 if (fMu0.IsMotherAResonance(nparents0-1-i) && fMu1.IsMotherAResonance(nparents1-1-i) &&
115 fMu0.GetParentPythiaLine(nparents0-1-i)==fMu1.GetParentPythiaLine(nparents1-1-i)) {
116 if (nparents0-1-i) SetFeedDown(nparents0-1-i);
117 return kTRUE;
118 }
119 }
120 return kFALSE;
55fd51b0 121}
122
123//====================================
124
125AliMUONTrackLight* AliMUONPairLight::GetMuon(Int_t index) {
126 /// return muon 0 or 1
127 if (index==0) return &fMu0;
128 else if (index==1) return &fMu1;
129 else{ printf ("Index can be either 0 or 1\n"); return 0;}
130 // else return &fMu1;
131}
132
133//====================================
134
135Int_t AliMUONPairLight::GetMuonMotherPDG(Int_t imuon, Int_t mother) {
136 /// return muon mother pdg code
137 if (imuon==0) return fMu0.GetParentPDGCode(mother);
138 else if (imuon==1) return fMu1.GetParentPDGCode(mother);
139 else { printf ("Index must be only 0 or 1\n"); return -999; }
140}
141
142//====================================
143void AliMUONPairLight::SetProcess(){
144 /// finds the process related to the muon pair (open charm/beauty, resonance,
145 /// uncorrelated...)
b88403f3 146
55fd51b0 147 AliMUONTrackLight *mu1 = &fMu0;
148 AliMUONTrackLight *mu2 = &fMu1;
149
55fd51b0 150 // check if the two muons are correlated
151 // first check if they come from the same hadron (resonance or beauty/charm meson)
152 Int_t npar1 = mu1->GetNParents();
153 Int_t npar2 = mu2->GetNParents();
55fd51b0 154 for (Int_t imoth1 = npar1-1; imoth1>=0; imoth1--) {
155 Int_t lineMo1 = mu1->GetParentPythiaLine(imoth1);
55fd51b0 156 for (Int_t imoth2 = npar2-1; imoth2>=0; imoth2--) {
157 Int_t lineMo2 = mu2->GetParentPythiaLine(imoth2);
158 if(lineMo1 == lineMo2) {
b88403f3 159 //reject "diquark" mothers
160 if(mu1->IsDiquark(mu1->GetParentPDGCode(imoth1)))return;
161// if(IsDiquark(mu1->GetParentPDGCode(imoth1))) return;
55fd51b0 162 this->SetCorrelated(kTRUE);
163 this->SetCauseOfCorrelation(mu1->GetParentPDGCode(imoth1));
164 if(!IsAResonance()) fCreationProcess = 3;
165 else fCreationProcess = -1;
b88403f3 166 return;
55fd51b0 167 }
168 }
91e620e2 169 }
170
171 //now, check if we have a correlated pi/K:
172 if(this->IsDimuonFromCorrPiK()){
173 this->SetCorrelated(kTRUE);
174 this->SetCauseOfCorrelation(mu1->GetParentPDGCode(0));
175 fCreationProcess = -1;
176 }
177
55fd51b0 178 // if Open Beauty/Charm we can have 3 creation processes
179 // (pair creation [0], gluon splitting [1] or flavour excitation [2])
55fd51b0 180 // 1.) gluon splitting: gluon (stored with index 2, id=21) must be the same
b88403f3 181 Int_t flavPar1 = mu1->GetParentFlavour(0);
182 Int_t flavPar2 = mu2->GetParentFlavour(0);
183 for (Int_t imoth1 = 0; imoth1 < 4; imoth1++) {
184 Int_t lineMo1 = mu1->GetQuarkPythiaLine(imoth1);
185 for (Int_t imoth2 = 0; imoth2 < 4; imoth2++) {
186 Int_t lineMo2 = mu2->GetQuarkPythiaLine(imoth2);
187 if(lineMo1 == lineMo2 && mu1->GetQuarkPDGCode(imoth1) == 21) {
188 //now, check also that the string fragmented into two hadrons
189 //of the same flavour (string usually splits into many hadrons
190 //among which there are mostly soft particles)
191 if(flavPar1 == flavPar2){
192 this->SetCorrelated(kTRUE);
193 if(GetCauseOfCorrelation() == -1)
194 this->SetCauseOfCorrelation(mu1->GetQuarkPDGCode(imoth1));
195
196 fCreationProcess = 1;
197 return;
198 }
199 }
55fd51b0 200 }
55fd51b0 201 }
91e620e2 202
55fd51b0 203 Int_t line1 = mu1->GetQuarkPythiaLine(2); //[2] ... very first quark
204 Int_t line2 = mu2->GetQuarkPythiaLine(2);
b88403f3 205
206 Int_t line6or7[2] = {-1, -1}; //holds the index of quark in line 6 or 7
207 Int_t flavourLine6or7[2] = {-1, -1};
208 // 2.) pair creation: if pythia line 6 of one track *and* pythia line 7 of second track
209 // are filled with a Q and Qbar
210 for (Int_t imoth1 = 3; imoth1>=0; imoth1--) {
211 Int_t lineMo1 = mu1->GetQuarkPythiaLine(imoth1);
212 Int_t flavour1 = TMath::Abs(mu1->GetQuarkPDGCode(imoth1));
213 if(lineMo1 == 6 || lineMo1 == 7){ //track 0 has a mother in line 6 or 7
214 line6or7[0] = imoth1;
215 flavourLine6or7[0] = flavour1;
216 }
217 for (Int_t imoth2 = 3; imoth2>=0; imoth2--) {
218 Int_t lineMo2 = mu2->GetQuarkPythiaLine(imoth2);
219 Int_t flavour2 = TMath::Abs(mu2->GetQuarkPDGCode(imoth2));
220 if(lineMo2 == 6 || lineMo2 == 7){ //track 1 has a mother in line 6 or 7
221 line6or7[1] = imoth2;
222 flavourLine6or7[1] = flavour2;
223 }
224 if((line6or7[0] > 0 && line6or7[1] > 0) && //both tracks must have an entry in line 6 or 7
225 (flavourLine6or7[0] == 4 || flavourLine6or7[0] == 5) && //this entry must be a c or b quark
226 (flavourLine6or7[1] == 4 || flavourLine6or7[1] == 5) && // == " ==
227 (flavPar1 == flavPar2)){ //make sure that the first hadronised parents of the 2 tracks are of the same flavour
228 this->SetCorrelated(kTRUE);
229 fCreationProcess = 0;
230 return;
231 }
55fd51b0 232 }
233 }
234
91e620e2 235 // 3.)flavour excitation: if pythia line 6 of one track *and* pythia line 7 of second track
236 // are filled with a Q and Qbar and if in addition there is another heavy quark in line(s) 4 and/or 5
b88403f3 237 Int_t line2or3[2] = {-1, -1}; //holds the index of g/q in line 2 or 3
238 Int_t flavourLine2or3[2] = {-1, -1};
239 for (Int_t imoth1 = 3; imoth1>=0; imoth1--) {
240 Int_t lineMo1 = mu1->GetQuarkPythiaLine(imoth1);
241 Int_t flavour1 = TMath::Abs(mu1->GetQuarkPDGCode(imoth1));
242 if(lineMo1 == 2 || lineMo1 == 3){ //track 0 has a mother in line 2 or 3
243 line2or3[0] = imoth1;
244 flavourLine2or3[0] = flavour1;
245 }
246 for (Int_t imoth2 = 3; imoth2>=0; imoth2--) {
247 Int_t lineMo2 = mu2->GetQuarkPythiaLine(imoth2);
248 Int_t flavour2 = TMath::Abs(mu2->GetQuarkPDGCode(imoth2));
249 if(lineMo2 == 2 || lineMo2 == 3){ //track 1 has a mother in line 2 or 3
250 line2or3[1] = imoth2;
251 flavourLine2or3[1] = flavour2;
252 }
253 if(((line6or7[0] > 0 && (flavourLine6or7[0] == 4 || flavourLine6or7[0] == 5)) && //first track has Q in line 6 or 7
254 (line2or3[1] > 0 && (flavourLine2or3[1] == 21 || flavourLine2or3[1] < 10))) || //second track has a g/q in line 2 or 3
255 ((line6or7[1] > 0 && (flavourLine6or7[1] == 4 || flavourLine6or7[1] == 5)) && //or the same,
256 (line2or3[0] > 0 && (flavourLine2or3[0] == 21 || flavourLine2or3[0] < 10)))){ // swapping the track's indices
257 //now, check also that the string fragmented into two hadrons
258 //of the same flavour (string usually splits into many hadrons
259 //among which there are mostly soft particles)
260 if(flavPar1 == flavPar2){
261 this->SetCorrelated(kTRUE);
262 fCreationProcess = 2;
263 return;
264 }
265 }
266 }
267 }
268
269 //now flag (rare) processes in which only the incoming parton in line 2 or 3
270 //radiates a gluon which produces a QQbar pair:
271 //exclude the light quarks
272 if(line1 == line2 && (line1 == 2 || line1 == 3)){
273 if((TMath::Abs(mu1->GetQuarkPDGCode(1)) == 4 && TMath::Abs(mu2->GetQuarkPDGCode(1)) == 4) ||
274 (TMath::Abs(mu1->GetQuarkPDGCode(1)) == 5 && TMath::Abs(mu2->GetQuarkPDGCode(1)) == 5)){
275
276 //now, check also that the string fragmented into two hadrons
277 //of the same flavour (string usually splits into many hadrons
278 //among which there are mostly soft particles)
279 if(flavPar1 == flavPar2){
280
281 this->SetCorrelated(kTRUE);
282 fCreationProcess = 1;
283 if(GetCauseOfCorrelation() == -1){
284 this->SetCauseOfCorrelation(mu1->GetQuarkPDGCode(1));
285 }
286 return;
287 }
288 }
55fd51b0 289 }
91e620e2 290
291 //in initial-state-radiation produced QQbar events the "mother quark"
292 //is acknowledged as the second quark [1] and sits in line 2 or 3
293 //is part of gluon splitting
294 line1 = mu1->GetQuarkPythiaLine(1); //[1] ... direct mother quark of outgoing quark in [0]
295 line2 = mu2->GetQuarkPythiaLine(1);
296 if(line1 == line2 && (line1 == 2 || line1 == 3)){
297 if((TMath::Abs(mu1->GetQuarkPDGCode(0)) == 4 && TMath::Abs(mu2->GetQuarkPDGCode(0)) == 4) ||
298 (TMath::Abs(mu1->GetQuarkPDGCode(0)) == 5 && TMath::Abs(mu2->GetQuarkPDGCode(0)) == 5)){
299
300 //now, check also that the string fragmented into two hadrons
301 //of the same flavour (string usually splits into many hadrons
302 //among which there are mostly soft particles)
303 if(flavPar1 == flavPar2){
304
305 this->SetCorrelated(kTRUE);
306 fCreationProcess = 1;
307 if(GetCauseOfCorrelation() == -1){
308 this->SetCauseOfCorrelation(mu1->GetQuarkPDGCode(1)); //should be flagged as initial state radiation?
309 }
310 return;
311 }
312 }
313 }
314
315 //in final-state-radiation produced QQbar events the "mother quark"
316 //is acknowledged as the first quark [1] and sits in line 6 or 7
317 //is part of gluon splitting
318 line1 = mu1->GetQuarkPythiaLine(1); //[1] ... direct mother quark
319 line2 = mu2->GetQuarkPythiaLine(1);
320 if(line1 == line2 && (line1 == 6 || line1 == 7)){
321 if((TMath::Abs(mu1->GetQuarkPDGCode(0)) == 4 && TMath::Abs(mu2->GetQuarkPDGCode(0)) == 4) ||
322 (TMath::Abs(mu1->GetQuarkPDGCode(0)) == 5 && TMath::Abs(mu2->GetQuarkPDGCode(0)) == 5)){
323
324 //now, check also that the string fragmented into two hadrons
325 //of the same flavour (string usually splits into many hadrons
326 //among which there are mostly soft particles)
327 if(flavPar1 == flavPar2){
328
329 this->SetCorrelated(kTRUE);
330 fCreationProcess = 1;
331 if(GetCauseOfCorrelation() == -1){
332 this->SetCauseOfCorrelation(mu1->GetQuarkPDGCode(1));
333 }
334 return;
335 }
336 }
337 }
55fd51b0 338}
339
340//====================================
c3aca76f 341void AliMUONPairLight::SetMuons(const AliMUONTrackLight& mu0, const AliMUONTrackLight& mu1){
55fd51b0 342 /// set the two muons
343 fMu0 = mu0;
344 fMu1 = mu1;
345 this->SetProcess();
346}
347
348//====================================
57e2ad1a 349void AliMUONPairLight::PrintInfo(const Option_t* opt){
55fd51b0 350 /// print information about muon pairs
351 /// Options:
352 /// - "H" single muons' decay histories
353 /// - "K" dimuon kinematics
354 /// - "F" dimuon flags
355 /// - "A" all variables
356 TString options(opt);
357 options.ToUpper();
358
359 if(options.Contains("H") || options.Contains("A")){//muon decay histories
360
361 AliMUONTrackLight *mu1 = &fMu0;
362 AliMUONTrackLight *mu2 = &fMu1;
363
364 printf("========= History =======================\n");
365 printf("first muon");
366 mu1->PrintInfo("H");
367 printf("second muon");
368 mu2->PrintInfo("H");
369 printf("=========================================\n");
370 }
371 if(options.Contains("F") || options.Contains("A")){//flags
372 printf("the flags set for this muon pair are:\n");
373 printf("=====================================\n");
374 if(this->IsOneTrackNotAMuon()) printf("(*) one rec. track is not a muon\n");
375 fIsCorrelated ? printf("(*) it is a correlated pair\n") : printf("(*) it is not a correlated pair\n");
376 if(IsOpenCharm()) printf("(*) correlated open charm: ");
377 if(IsOpenBeauty()) printf("(*) correlated open beauty: ");
378 if(IsOpenCharm() || IsOpenBeauty()){
379 switch(fCreationProcess){
380 case 0:
381 printf("pair creation");
382 break;
383 case 1:
384 printf("gluon splitting");
385 break;
386 case 2:
387 printf("flavour excitation");
388 break;
389 case 3:
390 printf("both muons come from same fragmented mother");
391 break;
392 }
393 if(this->GetMuon(0)->GetOscillation() || this->GetMuon(1)->GetOscillation())
394 printf("... where oscillation occured\n");
395 else{
396 if(IsOpenBeauty())
397 printf(" (no oscillation)\n");
398 else
399 printf("\n");
400 }
401 }
b88403f3 402 IsAResonance() ? printf("(*) it is a resonance: %d\n", this->GetMuonMotherPDG(0, fIsFeedDown)) : printf("(*) it is not a resonance\n");
403 fIsFeedDown ? printf("(*) mother has feed-down: %d --> %d\n", this->GetMuonMotherPDG(0,fMu0.GetNParents()-2), this->GetMuonMotherPDG(0,fMu0.GetNParents()-1)) : printf("(*) no feed-down\n");
55fd51b0 404 printf("=====================================\n");
405 }
406 if(options.Contains("K") || options.Contains("A")){//dimuon kinematics
407 Double_t *vtx = this->GetMuon(0)->GetVertex();
408 TLorentzVector momRec = this->GetPRec();
409 TLorentzVector momGen = this->GetPGen();
410 printf("the dimuon charge is %d\n", this->GetCharge());
411 printf("primary Vertex: Vx = %1.3f, Vy = %1.3f, Vz = %1.3f\n", vtx[0], vtx[1], vtx[2]);
412 printf("Generated: Px = %1.3f, Py = %1.3f, Pz = %1.3f\n", momGen.Px(), momGen.Py(), momGen.Pz());
413 printf("Reconstructed: Px = %1.3f, Py = %1.3f, Pz = %1.3f\n", momRec.Px(), momRec.Py(), momRec.Pz());
414 //rapidity, pT, angles, ...
91e620e2 415 printf("Rec. variables: mass %1.3f, pT %1.3f, pseudo-rapidity %1.3f, openingAngle %1.3f (%1.3f degree), theta %1.3f (%1.3f degree), phi %1.3f (%1.3f degree)\n",
416 momRec.M(), momRec.Pt(), momRec.Eta(),
55fd51b0 417 TMath::Pi()/180.*this->GetOpeningAngle(), this->GetOpeningAngle(),
418 momRec.Theta(), 180./TMath::Pi() * momRec.Theta(),
419 momRec.Phi(), 180./TMath::Pi() * momRec.Phi());
420 }
421}
422
b88403f3 423//====================================
55fd51b0 424Double_t AliMUONPairLight::GetOpeningAngle() {
b88403f3 425 /// opening angle between the two muons in the lab frame (in degrees)
55fd51b0 426 TLorentzVector pRecMu0 = fMu0.GetPRec();
427 TLorentzVector pRecMu1 = fMu1.GetPRec();
428 TVector3 pRecMu03 = pRecMu0.Vect();
429 TVector3 pRecMu13 = pRecMu1.Vect();
430 Double_t scalar = pRecMu03.Dot(pRecMu13);
431 Double_t modMu0 = pRecMu03.Mag();
432 Double_t modMu1 = pRecMu13.Mag();
433 Double_t theta = (TMath::ACos(scalar/(modMu0*modMu1)))*(180./TMath::Pi());
434 return theta;
435}
91e620e2 436//================================================
437Bool_t AliMUONPairLight::IsDimuonFromCorrPiK(){
438 ///check if we have a correlated pi/K
439
440 AliMUONTrackLight *mu0 = this->GetMuon(0), *mu1 = this->GetMuon(1);
441 Bool_t fromSameLine = kFALSE;
442 if (mu0->IsParentPionOrKaon() &&
443 mu1->IsParentPionOrKaon() &&
444 mu1->GetQuarkPythiaLine() == mu0->GetQuarkPythiaLine()
445 ) fromSameLine = kTRUE;
446
447 return fromSameLine;
448}