]>
Commit | Line | Data |
---|---|---|
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 | ||
18 | //=================================================================== | |
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 | |
32 | //=================================================================== | |
33 | ||
34 | ||
35 | //MUON classes | |
36 | #include "AliMUONPairLight.h" | |
37 | //Root classes | |
38 | #include "TString.h" | |
39 | ||
40 | ClassImp(AliMUONPairLight) | |
41 | ||
42 | //==================================== | |
43 | AliMUONPairLight::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 | ||
58 | AliMUONPairLight::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 | ||
79 | AliMUONPairLight::~AliMUONPairLight(){ | |
80 | /// destructor | |
81 | } | |
82 | ||
83 | //==================================== | |
84 | ||
85 | Bool_t AliMUONPairLight::IsAResonance(){ | |
86 | /// checks if muon pair comes from a resonance decay | |
87 | if (!fIsCorrelated) return kFALSE; //if muons not correlated, cannot be a resonance | |
88 | //if muons are correlated, check if the PDG of the | |
89 | //common mother is a resonance | |
b88403f3 | 90 | Int_t nparents0 = fMu0.GetNParents(); |
91 | Int_t nparents1 = fMu1.GetNParents(); | |
55fd51b0 | 92 | |
b88403f3 | 93 | Int_t minP = TMath::Min(nparents0, nparents1); |
94 | for (Int_t i = 0 ; i < minP; i++) { | |
95 | if (fMu0.IsMotherAResonance(nparents0-1-i) && fMu1.IsMotherAResonance(nparents1-1-i) && | |
96 | fMu0.GetParentPythiaLine(nparents0-1-i)==fMu1.GetParentPythiaLine(nparents1-1-i)) { | |
97 | if (nparents0-1-i) SetFeedDown(nparents0-1-i); | |
98 | return kTRUE; | |
99 | } | |
100 | } | |
101 | return kFALSE; | |
55fd51b0 | 102 | } |
103 | ||
104 | //==================================== | |
105 | ||
106 | AliMUONTrackLight* AliMUONPairLight::GetMuon(Int_t index) { | |
107 | /// return muon 0 or 1 | |
108 | if (index==0) return &fMu0; | |
109 | else if (index==1) return &fMu1; | |
110 | else{ printf ("Index can be either 0 or 1\n"); return 0;} | |
111 | // else return &fMu1; | |
112 | } | |
113 | ||
114 | //==================================== | |
115 | ||
116 | Int_t AliMUONPairLight::GetMuonMotherPDG(Int_t imuon, Int_t mother) { | |
117 | /// return muon mother pdg code | |
118 | if (imuon==0) return fMu0.GetParentPDGCode(mother); | |
119 | else if (imuon==1) return fMu1.GetParentPDGCode(mother); | |
120 | else { printf ("Index must be only 0 or 1\n"); return -999; } | |
121 | } | |
122 | ||
123 | //==================================== | |
124 | void AliMUONPairLight::SetProcess(){ | |
125 | /// finds the process related to the muon pair (open charm/beauty, resonance, | |
126 | /// uncorrelated...) | |
b88403f3 | 127 | |
55fd51b0 | 128 | AliMUONTrackLight *mu1 = &fMu0; |
129 | AliMUONTrackLight *mu2 = &fMu1; | |
130 | ||
55fd51b0 | 131 | // check if the two muons are correlated |
132 | // first check if they come from the same hadron (resonance or beauty/charm meson) | |
133 | Int_t npar1 = mu1->GetNParents(); | |
134 | Int_t npar2 = mu2->GetNParents(); | |
55fd51b0 | 135 | for (Int_t imoth1 = npar1-1; imoth1>=0; imoth1--) { |
136 | Int_t lineMo1 = mu1->GetParentPythiaLine(imoth1); | |
55fd51b0 | 137 | for (Int_t imoth2 = npar2-1; imoth2>=0; imoth2--) { |
138 | Int_t lineMo2 = mu2->GetParentPythiaLine(imoth2); | |
139 | if(lineMo1 == lineMo2) { | |
b88403f3 | 140 | //reject "diquark" mothers |
141 | if(mu1->IsDiquark(mu1->GetParentPDGCode(imoth1)))return; | |
142 | // if(IsDiquark(mu1->GetParentPDGCode(imoth1))) return; | |
55fd51b0 | 143 | this->SetCorrelated(kTRUE); |
144 | this->SetCauseOfCorrelation(mu1->GetParentPDGCode(imoth1)); | |
145 | if(!IsAResonance()) fCreationProcess = 3; | |
146 | else fCreationProcess = -1; | |
b88403f3 | 147 | return; |
55fd51b0 | 148 | } |
149 | } | |
150 | } | |
55fd51b0 | 151 | // if Open Beauty/Charm we can have 3 creation processes |
152 | // (pair creation [0], gluon splitting [1] or flavour excitation [2]) | |
55fd51b0 | 153 | // 1.) gluon splitting: gluon (stored with index 2, id=21) must be the same |
b88403f3 | 154 | Int_t flavPar1 = mu1->GetParentFlavour(0); |
155 | Int_t flavPar2 = mu2->GetParentFlavour(0); | |
156 | for (Int_t imoth1 = 0; imoth1 < 4; imoth1++) { | |
157 | Int_t lineMo1 = mu1->GetQuarkPythiaLine(imoth1); | |
158 | for (Int_t imoth2 = 0; imoth2 < 4; imoth2++) { | |
159 | Int_t lineMo2 = mu2->GetQuarkPythiaLine(imoth2); | |
160 | if(lineMo1 == lineMo2 && mu1->GetQuarkPDGCode(imoth1) == 21) { | |
161 | //now, check also that the string fragmented into two hadrons | |
162 | //of the same flavour (string usually splits into many hadrons | |
163 | //among which there are mostly soft particles) | |
164 | if(flavPar1 == flavPar2){ | |
165 | this->SetCorrelated(kTRUE); | |
166 | if(GetCauseOfCorrelation() == -1) | |
167 | this->SetCauseOfCorrelation(mu1->GetQuarkPDGCode(imoth1)); | |
168 | ||
169 | fCreationProcess = 1; | |
170 | return; | |
171 | } | |
172 | } | |
55fd51b0 | 173 | } |
55fd51b0 | 174 | } |
55fd51b0 | 175 | Int_t line1 = mu1->GetQuarkPythiaLine(2); //[2] ... very first quark |
176 | Int_t line2 = mu2->GetQuarkPythiaLine(2); | |
b88403f3 | 177 | |
178 | Int_t line6or7[2] = {-1, -1}; //holds the index of quark in line 6 or 7 | |
179 | Int_t flavourLine6or7[2] = {-1, -1}; | |
180 | // 2.) pair creation: if pythia line 6 of one track *and* pythia line 7 of second track | |
181 | // are filled with a Q and Qbar | |
182 | for (Int_t imoth1 = 3; imoth1>=0; imoth1--) { | |
183 | Int_t lineMo1 = mu1->GetQuarkPythiaLine(imoth1); | |
184 | Int_t flavour1 = TMath::Abs(mu1->GetQuarkPDGCode(imoth1)); | |
185 | if(lineMo1 == 6 || lineMo1 == 7){ //track 0 has a mother in line 6 or 7 | |
186 | line6or7[0] = imoth1; | |
187 | flavourLine6or7[0] = flavour1; | |
188 | } | |
189 | for (Int_t imoth2 = 3; imoth2>=0; imoth2--) { | |
190 | Int_t lineMo2 = mu2->GetQuarkPythiaLine(imoth2); | |
191 | Int_t flavour2 = TMath::Abs(mu2->GetQuarkPDGCode(imoth2)); | |
192 | if(lineMo2 == 6 || lineMo2 == 7){ //track 1 has a mother in line 6 or 7 | |
193 | line6or7[1] = imoth2; | |
194 | flavourLine6or7[1] = flavour2; | |
195 | } | |
196 | if((line6or7[0] > 0 && line6or7[1] > 0) && //both tracks must have an entry in line 6 or 7 | |
197 | (flavourLine6or7[0] == 4 || flavourLine6or7[0] == 5) && //this entry must be a c or b quark | |
198 | (flavourLine6or7[1] == 4 || flavourLine6or7[1] == 5) && // == " == | |
199 | (flavPar1 == flavPar2)){ //make sure that the first hadronised parents of the 2 tracks are of the same flavour | |
200 | this->SetCorrelated(kTRUE); | |
201 | fCreationProcess = 0; | |
202 | return; | |
203 | } | |
55fd51b0 | 204 | } |
205 | } | |
206 | ||
b88403f3 | 207 | |
55fd51b0 | 208 | // 3.)flavour excitation: |
b88403f3 | 209 | Int_t line2or3[2] = {-1, -1}; //holds the index of g/q in line 2 or 3 |
210 | Int_t flavourLine2or3[2] = {-1, -1}; | |
211 | for (Int_t imoth1 = 3; imoth1>=0; imoth1--) { | |
212 | Int_t lineMo1 = mu1->GetQuarkPythiaLine(imoth1); | |
213 | Int_t flavour1 = TMath::Abs(mu1->GetQuarkPDGCode(imoth1)); | |
214 | if(lineMo1 == 2 || lineMo1 == 3){ //track 0 has a mother in line 2 or 3 | |
215 | line2or3[0] = imoth1; | |
216 | flavourLine2or3[0] = flavour1; | |
217 | } | |
218 | for (Int_t imoth2 = 3; imoth2>=0; imoth2--) { | |
219 | Int_t lineMo2 = mu2->GetQuarkPythiaLine(imoth2); | |
220 | Int_t flavour2 = TMath::Abs(mu2->GetQuarkPDGCode(imoth2)); | |
221 | if(lineMo2 == 2 || lineMo2 == 3){ //track 1 has a mother in line 2 or 3 | |
222 | line2or3[1] = imoth2; | |
223 | flavourLine2or3[1] = flavour2; | |
224 | } | |
225 | if(((line6or7[0] > 0 && (flavourLine6or7[0] == 4 || flavourLine6or7[0] == 5)) && //first track has Q in line 6 or 7 | |
226 | (line2or3[1] > 0 && (flavourLine2or3[1] == 21 || flavourLine2or3[1] < 10))) || //second track has a g/q in line 2 or 3 | |
227 | ((line6or7[1] > 0 && (flavourLine6or7[1] == 4 || flavourLine6or7[1] == 5)) && //or the same, | |
228 | (line2or3[0] > 0 && (flavourLine2or3[0] == 21 || flavourLine2or3[0] < 10)))){ // swapping the track's indices | |
229 | //now, check also that the string fragmented into two hadrons | |
230 | //of the same flavour (string usually splits into many hadrons | |
231 | //among which there are mostly soft particles) | |
232 | if(flavPar1 == flavPar2){ | |
233 | this->SetCorrelated(kTRUE); | |
234 | fCreationProcess = 2; | |
235 | return; | |
236 | } | |
237 | } | |
238 | } | |
239 | } | |
240 | ||
241 | //now flag (rare) processes in which only the incoming parton in line 2 or 3 | |
242 | //radiates a gluon which produces a QQbar pair: | |
243 | //exclude the light quarks | |
244 | if(line1 == line2 && (line1 == 2 || line1 == 3)){ | |
245 | if((TMath::Abs(mu1->GetQuarkPDGCode(1)) == 4 && TMath::Abs(mu2->GetQuarkPDGCode(1)) == 4) || | |
246 | (TMath::Abs(mu1->GetQuarkPDGCode(1)) == 5 && TMath::Abs(mu2->GetQuarkPDGCode(1)) == 5)){ | |
247 | ||
248 | //now, check also that the string fragmented into two hadrons | |
249 | //of the same flavour (string usually splits into many hadrons | |
250 | //among which there are mostly soft particles) | |
251 | if(flavPar1 == flavPar2){ | |
252 | ||
253 | this->SetCorrelated(kTRUE); | |
254 | fCreationProcess = 1; | |
255 | if(GetCauseOfCorrelation() == -1){ | |
256 | this->SetCauseOfCorrelation(mu1->GetQuarkPDGCode(1)); | |
257 | } | |
258 | return; | |
259 | } | |
260 | } | |
55fd51b0 | 261 | } |
262 | } | |
263 | ||
264 | //==================================== | |
265 | void AliMUONPairLight::SetMuons(AliMUONTrackLight mu0, AliMUONTrackLight mu1){ | |
266 | /// set the two muons | |
267 | fMu0 = mu0; | |
268 | fMu1 = mu1; | |
269 | this->SetProcess(); | |
270 | } | |
271 | ||
272 | //==================================== | |
273 | void AliMUONPairLight::PrintInfo(Option_t* opt){ | |
274 | /// print information about muon pairs | |
275 | /// Options: | |
276 | /// - "H" single muons' decay histories | |
277 | /// - "K" dimuon kinematics | |
278 | /// - "F" dimuon flags | |
279 | /// - "A" all variables | |
280 | TString options(opt); | |
281 | options.ToUpper(); | |
282 | ||
283 | if(options.Contains("H") || options.Contains("A")){//muon decay histories | |
284 | ||
285 | AliMUONTrackLight *mu1 = &fMu0; | |
286 | AliMUONTrackLight *mu2 = &fMu1; | |
287 | ||
288 | printf("========= History =======================\n"); | |
289 | printf("first muon"); | |
290 | mu1->PrintInfo("H"); | |
291 | printf("second muon"); | |
292 | mu2->PrintInfo("H"); | |
293 | printf("=========================================\n"); | |
294 | } | |
295 | if(options.Contains("F") || options.Contains("A")){//flags | |
296 | printf("the flags set for this muon pair are:\n"); | |
297 | printf("=====================================\n"); | |
298 | if(this->IsOneTrackNotAMuon()) printf("(*) one rec. track is not a muon\n"); | |
299 | fIsCorrelated ? printf("(*) it is a correlated pair\n") : printf("(*) it is not a correlated pair\n"); | |
300 | if(IsOpenCharm()) printf("(*) correlated open charm: "); | |
301 | if(IsOpenBeauty()) printf("(*) correlated open beauty: "); | |
302 | if(IsOpenCharm() || IsOpenBeauty()){ | |
303 | switch(fCreationProcess){ | |
304 | case 0: | |
305 | printf("pair creation"); | |
306 | break; | |
307 | case 1: | |
308 | printf("gluon splitting"); | |
309 | break; | |
310 | case 2: | |
311 | printf("flavour excitation"); | |
312 | break; | |
313 | case 3: | |
314 | printf("both muons come from same fragmented mother"); | |
315 | break; | |
316 | } | |
317 | if(this->GetMuon(0)->GetOscillation() || this->GetMuon(1)->GetOscillation()) | |
318 | printf("... where oscillation occured\n"); | |
319 | else{ | |
320 | if(IsOpenBeauty()) | |
321 | printf(" (no oscillation)\n"); | |
322 | else | |
323 | printf("\n"); | |
324 | } | |
325 | } | |
b88403f3 | 326 | IsAResonance() ? printf("(*) it is a resonance: %d\n", this->GetMuonMotherPDG(0, fIsFeedDown)) : printf("(*) it is not a resonance\n"); |
327 | 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 | 328 | printf("=====================================\n"); |
329 | } | |
330 | if(options.Contains("K") || options.Contains("A")){//dimuon kinematics | |
331 | Double_t *vtx = this->GetMuon(0)->GetVertex(); | |
332 | TLorentzVector momRec = this->GetPRec(); | |
333 | TLorentzVector momGen = this->GetPGen(); | |
334 | printf("the dimuon charge is %d\n", this->GetCharge()); | |
335 | printf("primary Vertex: Vx = %1.3f, Vy = %1.3f, Vz = %1.3f\n", vtx[0], vtx[1], vtx[2]); | |
336 | printf("Generated: Px = %1.3f, Py = %1.3f, Pz = %1.3f\n", momGen.Px(), momGen.Py(), momGen.Pz()); | |
337 | printf("Reconstructed: Px = %1.3f, Py = %1.3f, Pz = %1.3f\n", momRec.Px(), momRec.Py(), momRec.Pz()); | |
338 | //rapidity, pT, angles, ... | |
339 | printf("Rec. variables: 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", | |
340 | momRec.Pt(), momRec.Eta(), | |
341 | TMath::Pi()/180.*this->GetOpeningAngle(), this->GetOpeningAngle(), | |
342 | momRec.Theta(), 180./TMath::Pi() * momRec.Theta(), | |
343 | momRec.Phi(), 180./TMath::Pi() * momRec.Phi()); | |
344 | } | |
345 | } | |
346 | ||
b88403f3 | 347 | //==================================== |
55fd51b0 | 348 | Double_t AliMUONPairLight::GetOpeningAngle() { |
b88403f3 | 349 | /// opening angle between the two muons in the lab frame (in degrees) |
55fd51b0 | 350 | TLorentzVector pRecMu0 = fMu0.GetPRec(); |
351 | TLorentzVector pRecMu1 = fMu1.GetPRec(); | |
352 | TVector3 pRecMu03 = pRecMu0.Vect(); | |
353 | TVector3 pRecMu13 = pRecMu1.Vect(); | |
354 | Double_t scalar = pRecMu03.Dot(pRecMu13); | |
355 | Double_t modMu0 = pRecMu03.Mag(); | |
356 | Double_t modMu1 = pRecMu13.Mag(); | |
357 | Double_t theta = (TMath::ACos(scalar/(modMu0*modMu1)))*(180./TMath::Pi()); | |
358 | return theta; | |
359 | } |