New class for selecting clean V0s with kinematic cuts
[u/mrichter/AliRoot.git] / ANALYSIS / AliESDv0KineCuts.cxx
CommitLineData
7cd657f1 1/**************************************************************************\r
2 * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *\r
3 * *\r
4 * Author: The ALICE Off-line Project. *\r
5 * Contributors are mentioned in the code where appropriate. *\r
6 * *\r
7 * Permission to use, copy, modify and distribute this software and its *\r
8 * documentation strictly for non-commercial purposes is hereby granted *\r
9 * without fee, provided that the above copyright notice appears in all *\r
10 * copies and that both the copyright notice and this permission notice *\r
11 * appear in the supporting documentation. The authors make no claims *\r
12 * about the suitability of this software for any purpose. It is *\r
13 * provided "as is" without express or implied warranty. *\r
14 **************************************************************************/\r
15\r
16/*\r
17 * author: M.Kalisky@gsi.de\r
18 * 08/Dec/2010\r
19 *\r
20 * Description: This class allows with purely kinematical cuts\r
21 * to select clean samples of electrons, pions and protons from the\r
22 * V0 online finder ESD V0 candidates for PID and dectector resonse\r
23 * studies.\r
24 */\r
25\r
26#include <TVector3.h>\r
27#include <TDatabasePDG.h>\r
28\r
29#include "AliESDv0.h"\r
30#include "AliESDtrack.h"\r
31#include "AliESDEvent.h"\r
32#include "AliVEvent.h"\r
33#include "AliLog.h"\r
34#include "AliKFParticle.h"\r
35#include "AliVTrack.h"\r
36#include "AliKFVertex.h"\r
37\r
38#include "AliESDv0KineCuts.h"\r
39\r
40ClassImp(AliESDv0KineCuts)\r
41\r
42//____________________________________________________________________\r
43AliESDv0KineCuts::AliESDv0KineCuts() :\r
44 fEvent(0x0)\r
45 , fPrimaryVertex(0x0)\r
46 , fType(0)\r
47 , fMode(0)\r
48 , fTPCNcls(1)\r
49 , fTPCrefit(kTRUE)\r
50 , fTPCchi2perCls(4.0)\r
51 , fTPCclsRatio(0.6)\r
52 , fNoKinks(kTRUE)\r
53 , fGcutChi2NDF(10)\r
54 , fGcutInvMass(0.05)\r
55 , fK0cutChi2NDF(10)\r
56 , fLcutChi2NDF(10)\r
57{\r
58 //\r
59 // Default constructor\r
60 //\r
61\r
62 // default single track cuts\r
63 fTPCNcls = 1; // minimal number of the TPC clusters\r
64 fTPCrefit = kTRUE; // TPC refit\r
65 fTPCchi2perCls = 4.0; // chi2 per TPC cluster\r
66 fTPCclsRatio = 0.6; // minimal foun/findable TPC cluster ratio\r
67 fNoKinks = kTRUE; // kinks - no [kTRUE] or do not care [kFalse]\r
68\r
69\r
70 // default gamma cuts values\r
71 fGcutChi2NDF = 10; // Chi2NF cut value for the AliKFparticle gamma\r
72 fGcutCosPoint[0] = 0; // cos of the pointing angle [min, max]\r
73 fGcutCosPoint[1] = 0.02; // cos of the pointing angle [min, max]\r
74 fGcutDCA[0] = 0.; // DCA between the daughter tracks [min, max]\r
75 fGcutDCA[1] = 0.25; // DCA between the daughter tracks [min, max]\r
76 fGcutVertexR[0] = 3.; // radius of the conversion point [min, max]\r
77 fGcutVertexR[1] = 90.; // radius of the conversion point [min, max]\r
78 fGcutPsiPair[0] = 0.; // value of the psi pair cut [min, max]\r
79 fGcutPsiPair[1] = 0.05; // value of the psi pair cut [min, max]\r
80 fGcutInvMass = 0.05; // upper value on the gamma invariant mass\r
81 // default K0 cuts\r
82 fK0cutChi2NDF = 10; // Chi2NF cut value for the AliKFparticle K0\r
83 fK0cutCosPoint[0] = 0.; // cos of the pointing angle [min, max]\r
84 fK0cutCosPoint[1] = 0.02; // cos of the pointing angle [min, max]\r
85 fK0cutDCA[0] = 0.; // DCA between the daughter tracks [min, max]\r
86 fK0cutDCA[1] = 0.2; // DCA between the daughter tracks [min, max]\r
87 fK0cutVertexR[0] = 2.0; // radius of the decay point [min, max]\r
88 fK0cutVertexR[1] = 30.0; // radius of the decay point [min, max]\r
89 fK0cutInvMass[0] = 0.486; // invariant mass window\r
90 fK0cutInvMass[1] = 0.508; // invariant mass window\r
91 // Lambda & anti-Lambda cut values\r
92 fLcutChi2NDF = 10; // Chi2NF cut value for the AliKFparticle K0\r
93 fLcutCosPoint[0] = 0.; // cos of the pointing angle [min, max]\r
94 fLcutCosPoint[1] = 0.02; // cos of the pointing angle [min, max]\r
95 fLcutDCA[0] = 0.; // DCA between the daughter tracks [min, max]\r
96 fLcutDCA[1] = 0.2; // DCA between the daughter tracks [min, max]\r
97 fLcutVertexR[0] = 2.0; // radius of the decay point [min, max]\r
98 fLcutVertexR[1] = 40.0; // radius of the decay point [min, max]\r
99 fLcutInvMass[0] = 1.11; // invariant mass window\r
100 fLcutInvMass[1] = 1.12; // invariant mass window\r
101 \r
102}\r
103//____________________________________________________________________\r
104AliESDv0KineCuts::~AliESDv0KineCuts(){\r
105 //\r
106 // Destructor\r
107 //\r
108\r
109\r
110}\r
111//____________________________________________________________________\r
112AliESDv0KineCuts::AliESDv0KineCuts(const AliESDv0KineCuts &ref):\r
113 TObject(ref)\r
114 , fEvent(0x0)\r
115 , fPrimaryVertex(0x0)\r
116 , fType(0)\r
117 , fMode(0)\r
118 , fTPCNcls(1)\r
119 , fTPCrefit(kTRUE)\r
120 , fTPCchi2perCls(4.0)\r
121 , fTPCclsRatio(0.6)\r
122 , fNoKinks(kTRUE)\r
123 , fGcutChi2NDF(10)\r
124 , fGcutInvMass(0.05)\r
125 , fK0cutChi2NDF(10)\r
126 , fLcutChi2NDF(10)\r
127{\r
128 //\r
129 // Copy operator\r
130 //\r
131\r
132 ref.Copy(*this);\r
133}\r
134//____________________________________________________________________\r
135AliESDv0KineCuts &AliESDv0KineCuts::operator=(const AliESDv0KineCuts &ref){\r
136 //\r
137 // assignment operator\r
138 //\r
139 if(this != &ref)\r
140 ref.Copy(*this);\r
141 return *this; \r
142}\r
143//____________________________________________________________________\r
144void AliESDv0KineCuts::Copy(TObject &ref) const {\r
145 //\r
146 // Performs the copying of the object\r
147 //\r
148\r
149 TObject::Copy(ref);\r
150\r
151 AliESDv0KineCuts &target = dynamic_cast<AliESDv0KineCuts &>(ref);\r
152\r
153 // default single track cuts\r
154 target.fTPCNcls = fTPCNcls;\r
155 target.fTPCrefit = fTPCrefit;\r
156 target.fTPCchi2perCls = fTPCchi2perCls;\r
157 target.fTPCclsRatio = fTPCclsRatio;\r
158 target.fNoKinks = fNoKinks;\r
159\r
160\r
161 // default gamma cuts values\r
162 target.fGcutChi2NDF = fGcutChi2NDF;\r
163 memcpy(target.fGcutCosPoint, fGcutCosPoint, sizeof(Float_t) * 2);\r
164 memcpy(target.fGcutDCA, fGcutDCA, sizeof(Float_t) * 2); \r
165 memcpy(target.fGcutVertexR, fGcutVertexR, sizeof(Float_t) * 2);\r
166 memcpy(target.fGcutPsiPair, fGcutPsiPair, sizeof(Float_t) * 2);\r
167 target.fGcutInvMass = fGcutInvMass;\r
168 // default K0 cuts\r
169 target.fK0cutChi2NDF = fK0cutChi2NDF;\r
170 memcpy(target.fK0cutCosPoint, fK0cutCosPoint, sizeof(Float_t) * 2);\r
171 memcpy(target.fK0cutDCA, fK0cutDCA, sizeof(Float_t) * 2);\r
172 memcpy(target.fK0cutVertexR, fK0cutVertexR, sizeof(Float_t) * 2);\r
173 memcpy(target.fK0cutInvMass, fK0cutInvMass, sizeof(Float_t) * 2);\r
174 // Lambda & anti-Lambda cut values\r
175 target.fLcutChi2NDF = fLcutChi2NDF;\r
176 memcpy(target.fLcutCosPoint, fLcutCosPoint, sizeof(Float_t) * 2);\r
177 memcpy(target.fLcutDCA, fLcutDCA, sizeof(Float_t) * 2);\r
178 memcpy(target.fLcutVertexR, fLcutVertexR, sizeof(Float_t) * 2);\r
179 memcpy(target.fLcutInvMass, fLcutInvMass, sizeof(Float_t) * 2);\r
180 \r
181}\r
182//____________________________________________________________________\r
183Bool_t const AliESDv0KineCuts::ProcessV0(AliESDv0* const v0, Int_t &pdgV0, Int_t &pdgP, Int_t &pdgN){\r
184 //\r
185 // main user function\r
186 //\r
187\r
188 if(!v0) return kFALSE;\r
189 if(!fEvent){\r
190 AliErrorClass("No valid Event pointer available, provide it first");\r
191 return kFALSE;\r
192 }\r
193\r
194 if(!V0CutsCommon(v0)) return kFALSE;\r
195\r
196 const Int_t id = PreselectV0(v0);\r
197\r
198 if(!SingleTrackCuts(v0)) return kFALSE;\r
199\r
200 switch(id){\r
201 case kUndef:\r
202 return kFALSE;\r
203 case kGamma:\r
204 return CaseGamma(v0, pdgV0, pdgP, pdgN);\r
205 case kK0:\r
206 return CaseK0(v0, pdgV0, pdgP, pdgN);\r
207 case kLambda:\r
208 return CaseLambda(v0, pdgV0, pdgP, pdgN, 0);\r
209 case kALambda:\r
210 return CaseLambda(v0, pdgV0, pdgP, pdgN, 1);\r
211 default:\r
212 return kFALSE; \r
213 }\r
214\r
215 return kFALSE;\r
216}\r
217//____________________________________________________________________\r
218Bool_t const AliESDv0KineCuts::ProcessV0(AliESDv0* const v0, Int_t &pdgP, Int_t &pdgN){\r
219 //\r
220 // main user function, simplified if the V0 identity is not necessary\r
221 //\r
222\r
223 if(!v0) return kFALSE;\r
224 if(!fEvent){\r
225 AliErrorClass("No valid Event pointer available, provide it first");\r
226 return kFALSE;\r
227 }\r
228\r
229 Int_t idV0 = -1;\r
230 return ProcessV0(v0, idV0, pdgP, pdgN);\r
231\r
232}\r
233//____________________________________________________________________\r
234Int_t const AliESDv0KineCuts::PreselectV0(AliESDv0* const v0){\r
235 //\r
236 // Make a preselection (exclusive) of the V0 cadidates based on\r
237 // Armenteros plot\r
238 // the armenteros cut values are currently fixed and user is not able to set them via\r
239 // set funcions. The reason is that these cuts are optimized and furneter changes should \r
240 // not be necessary. To prove otherwise please study in detail before changing the values\r
241 //\r
242 \r
243 Float_t ap[2] = {-1., -1.};\r
244 Armenteros(v0, ap);\r
245 // for clarity\r
246 const Float_t alpha = ap[0];\r
247 const Float_t qt = ap[1];\r
248\r
249 // selection cuts \r
250 // - the reagions for different candidates must not overlap \r
251\r
252 // Gamma cuts\r
253 const Double_t cutAlphaG = 0.35; \r
254 const Double_t cutQTG = 0.05;\r
255 const Double_t cutAlphaG2[2] = {0.6, 0.8};\r
256 const Double_t cutQTG2 = 0.04;\r
257\r
258 // K0 cuts\r
259 const Float_t cutQTK0[2] = {0.1075, 0.215};\r
260 const Float_t cutAPK0[2] = {0.199, 0.8}; // parameters for curved QT cut\r
261 \r
262 // Lambda & A-Lambda cuts\r
263 const Float_t cutQTL = 0.03;\r
264 const Float_t cutAlphaL[2] = {0.35, 0.7};\r
265 const Float_t cutAlphaAL[2] = {-0.7, -0.35};\r
266 const Float_t cutAPL[3] = {0.107, -0.69, 0.5}; // parameters fir curved QT cut\r
267\r
268\r
269 if(kPurity == fMode){\r
270 // Check for Gamma candidates\r
271 if(qt < cutQTG){\r
272 if( (TMath::Abs(alpha) < cutAlphaG) ) return kGamma;\r
273 }\r
274 // additional region - should help high pT gammas\r
275 if(qt < cutQTG2){\r
276 if( (TMath::Abs(alpha) > cutAlphaG2[0]) && (TMath::Abs(alpha) < cutAlphaG2[1]) ) return kGamma;\r
277 }\r
278 }\r
279 if(kEffGamma == fMode){\r
280 if(qt < cutQTG) return kGamma;\r
281 }\r
282\r
283 \r
284 // Check for K0 candidates\r
285 Float_t q = cutAPK0[0] * TMath::Sqrt(TMath::Abs(1 - alpha*alpha/(cutAPK0[1]*cutAPK0[1])));\r
286 if( (qt > cutQTK0[0]) && (qt < cutQTK0[1]) && (qt > q) ){\r
287 return kK0;\r
288 }\r
289\r
290 // Check for Lambda candidates\r
291 q = cutAPL[0] * TMath::Sqrt(TMath::Abs(1 - ( (alpha + cutAPL[1]) * (alpha + cutAPL[1]) ) / (cutAPL[2]*cutAPL[2]) ));\r
292 if( (alpha > cutAlphaL[0]) && (alpha < cutAlphaL[1]) && (qt > cutQTL) && (qt < q) ){\r
293 return kLambda;\r
294 }\r
295\r
296 // Check for A-Lambda candidates\r
297 q = cutAPL[0] * TMath::Sqrt(TMath::Abs(1 - ( (alpha - cutAPL[1]) * (alpha - cutAPL[1]) ) / (cutAPL[2]*cutAPL[2]) ));\r
298 if( (alpha > cutAlphaAL[0]) && (alpha < cutAlphaAL[1]) && (qt > cutQTL) && (qt < q) ){\r
299 return kALambda;\r
300 }\r
301 \r
302 return kUndef;\r
303}\r
304//____________________________________________________________________\r
305Bool_t const AliESDv0KineCuts::SingleTrackCuts(AliESDv0 * const v0){\r
306 //\r
307 // apply single track cuts\r
308 // correct sign not relevat here\r
309 //\r
310\r
311 if(!v0) return kFALSE;\r
312 \r
313 Int_t pIndex = 0, nIndex = 0;\r
314 pIndex = v0->GetPindex();\r
315 nIndex = v0->GetNindex();\r
316 AliESDtrack* d[2];\r
317 d[0] = dynamic_cast<AliESDtrack*>(fEvent->GetTrack(pIndex));\r
318 d[1] = dynamic_cast<AliESDtrack*>(fEvent->GetTrack(nIndex));\r
319 \r
320 for(Int_t i=0; i<2; ++i){\r
321 if(!d[i]) return kFALSE;\r
322 \r
323 // status word\r
324 ULong_t status = d[i]->GetStatus();\r
325\r
326 // No. of TPC clusters leave to the users\r
327 if(d[i]->GetTPCNcls() < 1) return kFALSE;\r
328\r
329 // TPC refit\r
330 if(!(status & AliESDtrack::kTPCrefit)) return kFALSE;\r
331 \r
332 // Chi2 per TPC cluster\r
333 Int_t nTPCclusters = d[i]->GetTPCNcls();\r
334 Float_t chi2perTPCcluster = d[i]->GetTPCchi2()/Float_t(nTPCclusters);\r
335 if(chi2perTPCcluster > 4) return kFALSE;\r
336\r
337 // TPC cluster ratio\r
338 Float_t cRatioTPC = d[i]->GetTPCNclsF() > 0. ? static_cast<Float_t>(d[i]->GetTPCNcls())/static_cast<Float_t> (d[i]->GetTPCNclsF()) : 1.;\r
339 if(cRatioTPC < 0.6) return kFALSE;\r
340 \r
341 // kinks\r
342 if(d[i]->GetKinkIndex(0) != 0) return kFALSE;\r
343 \r
344 }\r
345\r
346 return kTRUE;\r
347}\r
348//____________________________________________________________________\r
349Bool_t const AliESDv0KineCuts::CaseGamma(AliESDv0* const v0, Int_t &pdgV0, Int_t &pdgP, Int_t &pdgN){\r
350 //\r
351 // process the gamma conversion candidate\r
352 //\r
353\r
354 if(!v0) return kFALSE;\r
355\r
356 AliVTrack* daughter[2];\r
357 Int_t pIndex = 0, nIndex = 0;\r
358\r
359 Bool_t sign = CheckSigns(v0);\r
360 if(sign){\r
361 pIndex = v0->GetPindex();\r
362 nIndex = v0->GetNindex();\r
363 }\r
364 else{\r
365 pIndex = v0->GetNindex();\r
366 nIndex = v0->GetPindex(); \r
367 }\r
368 daughter[0] = dynamic_cast<AliVTrack *>(fEvent->GetTrack(pIndex));\r
369 daughter[1] = dynamic_cast<AliVTrack *>(fEvent->GetTrack(nIndex));\r
370 if(!daughter[0] || !daughter[1]) return kFALSE;\r
371\r
372 AliKFParticle *kfMother = CreateMotherParticle(daughter[0], daughter[1], TMath::Abs(kElectron), TMath::Abs(kElectron));\r
373 if(!kfMother) return kFALSE;\r
374\r
375 AliESDtrack* d[2];\r
376 d[0] = dynamic_cast<AliESDtrack*>(fEvent->GetTrack(pIndex));\r
377 d[1] = dynamic_cast<AliESDtrack*>(fEvent->GetTrack(nIndex));\r
378\r
379 Float_t iMass = v0->GetEffMass(0, 0);\r
380\r
381 // cos pointing angle\r
382 Double_t cosPoint = v0->GetV0CosineOfPointingAngle();\r
383 cosPoint = TMath::ACos(cosPoint);\r
384\r
385 // DCA between daughters\r
386 Double_t dca = v0->GetDcaV0Daughters();\r
387\r
388 // Production vertex\r
389 Double_t x, y, z; \r
390 v0->GetXYZ(x,y,z);\r
391 Double_t r = TMath::Sqrt(x*x + y*y);\r
392\r
393 Double_t xy[2];\r
394 Double_t r2 = -1.;\r
395 if ( GetConvPosXY(d[0], d[1], xy) ){\r
396 r2 = TMath::Sqrt(xy[0]*xy[0] + xy[1]*xy[1]);\r
397 }\r
398\r
399 // psi pair \r
400 Double_t psiPair = PsiPair(v0);\r
401 \r
402 // V0 chi2/ndf\r
403 Double_t chi2ndf = kfMother->GetChi2()/kfMother->GetNDF();\r
404\r
405 if(kfMother) delete kfMother; \r
406 \r
407 // apply the cuts\r
408\r
409 if(iMass > fGcutInvMass) return kFALSE;\r
410\r
411 if(chi2ndf > fGcutChi2NDF) return kFALSE;\r
412\r
413 if(cosPoint < fGcutCosPoint[0] || cosPoint > fGcutCosPoint[1]) return kFALSE;\r
414\r
415 if(dca < fGcutDCA[0] || dca > fGcutDCA[1]) return kFALSE;\r
416\r
417 if(r < fGcutVertexR[0] || r > fGcutVertexR[1]) return kFALSE;\r
418\r
419 if(psiPair < fGcutPsiPair[0] || psiPair > fGcutPsiPair[1]) return kFALSE;\r
420 \r
421 // all cuts passed\r
422\r
423 pdgV0 = 22;\r
424 if(sign){\r
425 pdgP = -11;\r
426 pdgN = 11;\r
427 }\r
428 else{\r
429 pdgP = 11;\r
430 pdgN = -11;\r
431 }\r
432\r
433 return kTRUE;\r
434}\r
435//____________________________________________________________________\r
436Bool_t const AliESDv0KineCuts::CaseK0(AliESDv0* const v0, Int_t &pdgV0, Int_t &pdgP, Int_t &pdgN){\r
437 //\r
438 // process the K0 candidate\r
439 //\r
440\r
441 if(!v0) return kFALSE;\r
442 \r
443 AliVTrack* daughter[2];\r
444 Int_t pIndex = 0, nIndex = 0;\r
445 Bool_t sign = CheckSigns(v0);\r
446 if(sign){\r
447 pIndex = v0->GetPindex();\r
448 nIndex = v0->GetNindex();\r
449 }\r
450 else{\r
451 pIndex = v0->GetNindex();\r
452 nIndex = v0->GetPindex(); \r
453 }\r
454 \r
455 daughter[0] = dynamic_cast<AliVTrack *>(fEvent->GetTrack(pIndex));\r
456 daughter[1] = dynamic_cast<AliVTrack *>(fEvent->GetTrack(nIndex));\r
457 if(!daughter[0] || !daughter[1]) return kFALSE;\r
458\r
459 AliKFParticle *kfMother = CreateMotherParticle(daughter[0], daughter[1], TMath::Abs(kPiPlus), TMath::Abs(kPiPlus));\r
460 if(!kfMother) return kFALSE;\r
461\r
462 AliESDtrack* d[2];\r
463 d[0] = dynamic_cast<AliESDtrack*>(fEvent->GetTrack(pIndex));\r
464 d[1] = dynamic_cast<AliESDtrack*>(fEvent->GetTrack(nIndex));\r
465\r
466 Float_t iMass = v0->GetEffMass(2, 2);\r
467\r
468 // cos pointing angle\r
469 Double_t cosPoint = v0->GetV0CosineOfPointingAngle();\r
470 cosPoint = TMath::ACos(cosPoint);\r
471\r
472 // DCA between daughters\r
473 Double_t dca = v0->GetDcaV0Daughters();\r
474\r
475 // Production vertex\r
476 Double_t x, y, z; \r
477 v0->GetXYZ(x,y,z);\r
478\r
479 Double_t r = TMath::Sqrt(x*x + y*y); \r
480\r
481 // V0 chi2/ndf\r
482 Double_t chi2ndf = kfMother->GetChi2()/kfMother->GetNDF();\r
483 \r
484 if(kfMother) delete kfMother; \r
485\r
486 //\r
487 // apply the cuts\r
488 //\r
489 if(iMass < fK0cutInvMass[0] || iMass > fK0cutInvMass[1]) return kFALSE;\r
490\r
491 if(chi2ndf > fK0cutChi2NDF) return kFALSE;\r
492\r
493 if(cosPoint < fK0cutCosPoint[0] || cosPoint > fK0cutCosPoint[1]) return kFALSE;\r
494\r
495 if(dca < fK0cutDCA[0] || dca > fK0cutDCA[1]) return kFALSE;\r
496\r
497 if(r < fK0cutVertexR[0] || r > fK0cutVertexR[1]) return kFALSE;\r
498\r
499 // all cuts passed\r
500 pdgV0 = 310;\r
501 if(sign){\r
502 pdgP = 211;\r
503 pdgN = -211;\r
504 }\r
505 else{\r
506 pdgP = -211;\r
507 pdgN = 211;\r
508 }\r
509\r
510 return kTRUE;\r
511}\r
512//____________________________________________________________________\r
513Bool_t const AliESDv0KineCuts::CaseLambda(AliESDv0* const v0, Int_t &pdgV0, Int_t &pdgP, Int_t &pdgN, Int_t id){\r
514 //\r
515 // process teh Lambda and Anti-Lambda candidate\r
516 //\r
517 \r
518 if(!v0) return kFALSE;\r
519\r
520 const Double_t cL0mass=TDatabasePDG::Instance()->GetParticle(kLambda0)->Mass(); // PDG lambda mass\r
521\r
522 AliVTrack* daughter[2];\r
523 Int_t pIndex = 0, nIndex = 0;\r
524 Float_t mMass[2] = {-1., -1.};\r
525 Bool_t sign = CheckSigns(v0);\r
526 if(sign){\r
527 pIndex = v0->GetPindex();\r
528 nIndex = v0->GetNindex();\r
529 mMass[0] = v0->GetEffMass(4, 2);\r
530 mMass[1] = v0->GetEffMass(2, 4);\r
531 }\r
532 else{\r
533 pIndex = v0->GetNindex();\r
534 nIndex = v0->GetPindex(); \r
535 mMass[0] = v0->GetEffMass(2, 4);\r
536 mMass[1] = v0->GetEffMass(4, 2);\r
537 }\r
538 \r
539 daughter[0] = dynamic_cast<AliVTrack *>(fEvent->GetTrack(pIndex));\r
540 daughter[1] = dynamic_cast<AliVTrack *>(fEvent->GetTrack(nIndex));\r
541 if(!daughter[0] || !daughter[1]) return kFALSE;\r
542\r
543 AliKFParticle *kfMother[2] = {0x0, 0x0};\r
544 // Lambda\r
545 kfMother[0] = CreateMotherParticle(daughter[0], daughter[1], TMath::Abs(kProton), TMath::Abs(kPiPlus));\r
546 if(!kfMother[0]) return kFALSE;\r
547 \r
548 // Anti-Lambda\r
549 kfMother[1] = CreateMotherParticle(daughter[0], daughter[1], TMath::Abs(kPiPlus), TMath::Abs(kProton));\r
550 if(!kfMother[1]) return kFALSE;\r
551\r
552 Float_t dMass[2] = {TMath::Abs(mMass[0] - cL0mass), TMath::Abs(mMass[1] - cL0mass)};\r
553 \r
554 AliESDtrack* d[2];\r
555 d[0] = dynamic_cast<AliESDtrack*>(fEvent->GetTrack(pIndex));\r
556 d[1] = dynamic_cast<AliESDtrack*>(fEvent->GetTrack(nIndex));\r
557 if(!d[0] || !d[1]) return kFALSE;\r
558 \r
559 Float_t p[2] = {d[0]->GetP(), d[1]->GetP()}; \r
560\r
561 // check the 3 lambda - antilambda variables\r
562 Int_t check[2] = {-1, -1}; // 0 : lambda, 1 : antilambda\r
563 // 1) momentum of the daughter particles - proton is expected to have higher momentum than pion\r
564 check[0] = (p[0] > p[1]) ? 0 : 1;\r
565 // 2) mass of the mother particle\r
566 check[1] = (dMass[0] < dMass[1]) ? 0 : 1;\r
567 \r
568 // require positive correlation of (1) and (2)\r
569 if(check[0] != check[1]){\r
570 if(kfMother[0]) delete kfMother[0]; \r
571 if(kfMother[1]) delete kfMother[1]; \r
572 return kFALSE;\r
573 }\r
574\r
575 // now that the check[0] == check[1]\r
576 const Int_t type = check[0];\r
577\r
578 // require that the input armenteros preselection agree:\r
579 if(type != id) return kFALSE;\r
580\r
581 Float_t iMass =0.;\r
582 if(sign){\r
583 iMass = (type == 0) ? v0->GetEffMass(4, 2) : v0->GetEffMass(2, 4);\r
584 }\r
585 else{\r
586 iMass = (type == 0) ? v0->GetEffMass(2, 4) : v0->GetEffMass(4, 2);\r
587 }\r
588\r
589 // cos pointing angle\r
590 Double_t cosPoint = v0->GetV0CosineOfPointingAngle();\r
591 cosPoint = TMath::ACos(cosPoint);\r
592\r
593 // DCA between daughters\r
594 Double_t dca = v0->GetDcaV0Daughters();\r
595 \r
596 // Production vertex\r
597 Double_t x, y, z; \r
598 v0->GetXYZ(x,y,z);\r
599 Double_t r = TMath::Sqrt(x*x + y*y);\r
600\r
601 // proton - pion indices\r
602 Int_t ix[2] = {0, 1};\r
603 if(1 == type){\r
604 ix[0] = 1;\r
605 ix[1] = 0;\r
606 }\r
607\r
608 // V0 chi2/ndf\r
609 Double_t chi2ndf = kfMother[type]->GetChi2()/kfMother[type]->GetNDF();\r
610\r
611 if(kfMother[0]) delete kfMother[0]; \r
612 if(kfMother[1]) delete kfMother[1]; \r
613\r
614 //\r
615 // apply the cuts\r
616 //\r
617\r
618 if(iMass < fLcutInvMass[0] || iMass > fLcutInvMass[1]) return kFALSE;\r
619\r
620 if(chi2ndf > fLcutChi2NDF) return kFALSE;\r
621\r
622 if(cosPoint < fLcutCosPoint[0] || cosPoint > fLcutCosPoint[1]) return kFALSE;\r
623\r
624 if(dca < fLcutDCA[0] || dca > fLcutDCA[1]) return kFALSE;\r
625\r
626 if(r < fLcutVertexR[0] || r > fLcutVertexR[1]) return kFALSE;\r
627\r
628 // all cuts passed\r
629\r
630 if(0 == type){\r
631 pdgV0 = 3122;\r
632 if(sign){\r
633 pdgP = 2212;\r
634 pdgN = -211;\r
635 }\r
636 else{\r
637 pdgP = -211;\r
638 pdgN = 2212;\r
639 }\r
640 }\r
641 else{\r
642 pdgV0 = -3122;\r
643 if(sign){\r
644 pdgP = 211;\r
645 pdgN = -2212;\r
646 }\r
647 else{\r
648 pdgP = -2212;\r
649 pdgN = 211;\r
650 }\r
651 }\r
652\r
653 return kTRUE;\r
654}\r
655//____________________________________________________________________\r
656Bool_t const AliESDv0KineCuts::V0CutsCommon(AliESDv0 * const v0){\r
657 //\r
658 // V0 cuts common to all V0s\r
659 //\r
660\r
661 AliESDtrack* dN, *dP; \r
662 \r
663 dP = dynamic_cast<AliESDtrack *>(fEvent->GetTrack(v0->GetPindex()));\r
664 dN = dynamic_cast<AliESDtrack *>(fEvent->GetTrack(v0->GetNindex())); \r
665 \r
666 if(!dN || !dP) return kFALSE;\r
667\r
668 Int_t qP = dP->Charge();\r
669 Int_t qN = dN->Charge();\r
670\r
671 if((qP*qN) != -1) return kFALSE;\r
672\r
673 return kTRUE;\r
674}\r
675//____________________________________________________________________\r
676void const AliESDv0KineCuts::Armenteros(AliESDv0* const v0, Float_t val[2]){\r
677 //\r
678 // computes the Armenteros variables for given V0\r
679 // fills the histogram\r
680 // returns the values via "val"\r
681 //\r
682 \r
683 Double_t mn[3] = {0,0,0};\r
684 Double_t mp[3] = {0,0,0}; \r
685 Double_t mm[3] = {0,0,0}; \r
686\r
687 if(CheckSigns(v0)){\r
688 v0->GetNPxPyPz(mn[0],mn[1],mn[2]); //reconstructed cartesian momentum components of negative daughter\r
689 v0->GetPPxPyPz(mp[0],mp[1],mp[2]); //reconstructed cartesian momentum components of positive daughter\r
690 }\r
691 else{\r
692 v0->GetPPxPyPz(mn[0],mn[1],mn[2]); //reconstructed cartesian momentum components of negative daughter\r
693 v0->GetNPxPyPz(mp[0],mp[1],mp[2]); //reconstructed cartesian momentum components of positive daughter\r
694 }\r
695 v0->GetPxPyPz(mm[0],mm[1],mm[2]); //reconstructed cartesian momentum components of mother\r
696\r
697 TVector3 vecN(mn[0],mn[1],mn[2]);\r
698 TVector3 vecP(mp[0],mp[1],mp[2]);\r
699 TVector3 vecM(mm[0],mm[1],mm[2]);\r
700 \r
701 Double_t thetaP = acos((vecP * vecM)/(vecP.Mag() * vecM.Mag()));\r
702 Double_t thetaN = acos((vecN * vecM)/(vecN.Mag() * vecM.Mag()));\r
703 \r
704 Double_t alfa = ((vecP.Mag())*cos(thetaP)-(vecN.Mag())*cos(thetaN))/\r
705 ((vecP.Mag())*cos(thetaP)+(vecN.Mag())*cos(thetaN)) ;\r
706 Double_t qt = vecP.Mag()*sin(thetaP);\r
707\r
708 val[0] = alfa;\r
709 val[1] = qt;\r
710}\r
711//____________________________________________________________________\r
712Bool_t const AliESDv0KineCuts::CheckSigns(AliESDv0* const v0){\r
713 //\r
714 // check wheter the sign was correctly applied to \r
715 // V0 daughter tracks\r
716 //\r
717 \r
718 Bool_t correct = kFALSE;\r
719\r
720 Int_t pIndex = 0, nIndex = 0;\r
721 pIndex = v0->GetPindex();\r
722 nIndex = v0->GetNindex();\r
723 \r
724 AliESDtrack* d[2];\r
725 d[0] = dynamic_cast<AliESDtrack*>(fEvent->GetTrack(pIndex));\r
726 d[1] = dynamic_cast<AliESDtrack*>(fEvent->GetTrack(nIndex));\r
727\r
728 Int_t sign[2];\r
729 sign[0] = (int)d[0]->GetSign();\r
730 sign[1] = (int)d[1]->GetSign();\r
731 \r
732 if(-1 == sign[0] && 1 == sign[1]){\r
733 correct = kFALSE;\r
734 }\r
735 else{\r
736 correct = kTRUE;\r
737 }\r
738 \r
739 return correct;\r
740}\r
741//________________________________________________________________\r
742Double_t const AliESDv0KineCuts::PsiPair(AliESDv0* const v0) {\r
743 //\r
744 // Angle between daughter momentum plane and plane \r
745 // \r
746\r
747 if(!fEvent) return -1.;\r
748\r
749 Float_t magField = fEvent->GetMagneticField();\r
750\r
751 Int_t pIndex = -1;\r
752 Int_t nIndex = -1;\r
753 if(CheckSigns(v0)){\r
754 pIndex = v0->GetPindex();\r
755 nIndex = v0->GetNindex();\r
756 }\r
757 else{\r
758 pIndex = v0->GetNindex();\r
759 nIndex = v0->GetPindex(); \r
760 }\r
761 \r
762\r
763 AliESDtrack* daughter[2];\r
764\r
765 daughter[0] = dynamic_cast<AliESDtrack *>(fEvent->GetTrack(pIndex));\r
766 daughter[1] = dynamic_cast<AliESDtrack *>(fEvent->GetTrack(nIndex));\r
767\r
768 Double_t x, y, z;\r
769 v0->GetXYZ(x,y,z);//Reconstructed coordinates of V0; to be replaced by Markus Rammler's method in case of conversions!\r
770 \r
771 Double_t mn[3] = {0,0,0};\r
772 Double_t mp[3] = {0,0,0};\r
773 \r
774\r
775 v0->GetNPxPyPz(mn[0],mn[1],mn[2]);//reconstructed cartesian momentum components of negative daughter;\r
776 v0->GetPPxPyPz(mp[0],mp[1],mp[2]);//reconstructed cartesian momentum components of positive daughter; \r
777\r
778\r
779 Double_t deltat = 1.;\r
780 deltat = TMath::ATan(mp[2]/(TMath::Sqrt(mp[0]*mp[0] + mp[1]*mp[1])+1.e-13)) - TMath::ATan(mn[2]/(TMath::Sqrt(mn[0]*mn[0] + mn[1]*mn[1])+1.e-13));//difference of angles of the two daughter tracks with z-axis\r
781\r
782 Double_t radiussum = TMath::Sqrt(x*x + y*y) + 50;//radius to which tracks shall be propagated\r
783\r
784 Double_t momPosProp[3];\r
785 Double_t momNegProp[3];\r
786 \r
787 AliExternalTrackParam pt(*daughter[0]), nt(*daughter[1]);\r
788 \r
789 Double_t psiPair = 4.;\r
790\r
791 if(nt.PropagateTo(radiussum,magField) == 0)//propagate tracks to the outside\r
792 psiPair = -5.;\r
793 if(pt.PropagateTo(radiussum,magField) == 0)\r
794 psiPair = -5.;\r
795 pt.GetPxPyPz(momPosProp);//Get momentum vectors of tracks after propagation\r
796 nt.GetPxPyPz(momNegProp);\r
797 \r
798 Double_t pEle =\r
799 TMath::Sqrt(momNegProp[0]*momNegProp[0]+momNegProp[1]*momNegProp[1]+momNegProp[2]*momNegProp[2]);//absolute momentum value of negative daughter\r
800 Double_t pPos =\r
801 TMath::Sqrt(momPosProp[0]*momPosProp[0]+momPosProp[1]*momPosProp[1]+momPosProp[2]*momPosProp[2]);//absolute momentum value of positive daughter\r
802 \r
803 Double_t scalarproduct =\r
804 momPosProp[0]*momNegProp[0]+momPosProp[1]*momNegProp[1]+momPosProp[2]*momNegProp[2];//scalar product of propagated positive and negative daughters' momenta\r
805 \r
806 Double_t chipair = TMath::ACos(scalarproduct/(pEle*pPos));//Angle between propagated daughter tracks\r
807\r
808 psiPair = TMath::Abs(TMath::ASin(deltat/chipair)); \r
809\r
810 return psiPair; \r
811}\r
812//___________________________________________________________________\r
813Bool_t const AliESDv0KineCuts::GetConvPosXY(AliESDtrack * const ptrack, AliESDtrack * const ntrack, Double_t convpos[2]){\r
814 //\r
815 // recalculate the gamma conversion XY postition\r
816 //\r
817\r
818 const Double_t b = fEvent->GetMagneticField();\r
819\r
820 Double_t helixcenterpos[2];\r
821 GetHelixCenter(ptrack,b,ptrack->Charge(),helixcenterpos);\r
822\r
823 Double_t helixcenterneg[2];\r
824 GetHelixCenter(ntrack,b,ntrack->Charge(),helixcenterneg);\r
825\r
826 Double_t poshelix[6];\r
827 ptrack->GetHelixParameters(poshelix,b);\r
828 Double_t posradius = TMath::Abs(1./poshelix[4]);\r
829\r
830 Double_t neghelix[6];\r
831 ntrack->GetHelixParameters(neghelix,b);\r
832 Double_t negradius = TMath::Abs(1./neghelix[4]);\r
833\r
834 Double_t xpos = helixcenterpos[0];\r
835 Double_t ypos = helixcenterpos[1];\r
836 Double_t xneg = helixcenterneg[0];\r
837 Double_t yneg = helixcenterneg[1];\r
838\r
839 convpos[0] = (xpos*negradius + xneg*posradius)/(negradius+posradius);\r
840 convpos[1] = (ypos*negradius+ yneg*posradius)/(negradius+posradius);\r
841\r
842 return 1;\r
843}\r
844//___________________________________________________________________\r
845Bool_t const AliESDv0KineCuts::GetHelixCenter(AliESDtrack * const track, Double_t b,Int_t charge, Double_t center[2]){\r
846 //\r
847 // computes the center of the track helix\r
848 //\r
849 \r
850 Double_t pi = TMath::Pi();\r
851 \r
852 Double_t helix[6];\r
853 track->GetHelixParameters(helix,b);\r
854 \r
855 Double_t xpos = helix[5];\r
856 Double_t ypos = helix[0];\r
857 Double_t radius = TMath::Abs(1./helix[4]);\r
858 Double_t phi = helix[2];\r
859\r
860 if(phi < 0){\r
861 phi = phi + 2*pi;\r
862 }\r
863\r
864 phi -= pi/2.;\r
865 Double_t xpoint = radius * TMath::Cos(phi);\r
866 Double_t ypoint = radius * TMath::Sin(phi);\r
867\r
868 if(b<0){\r
869 if(charge > 0){\r
870 xpoint = - xpoint;\r
871 ypoint = - ypoint;\r
872 }\r
873\r
874 if(charge < 0){\r
875 xpoint = xpoint;\r
876 ypoint = ypoint;\r
877 }\r
878 }\r
879 if(b>0){\r
880 if(charge > 0){\r
881 xpoint = xpoint;\r
882 ypoint = ypoint;\r
883 }\r
884\r
885 if(charge < 0){\r
886 xpoint = - xpoint;\r
887 ypoint = - ypoint;\r
888 }\r
889 }\r
890 center[0] = xpos + xpoint;\r
891 center[1] = ypos + ypoint;\r
892\r
893 return 1;\r
894}\r
895//___________________________________________________________________\r
896AliKFParticle *AliESDv0KineCuts::CreateMotherParticle(const AliVTrack* const pdaughter, const AliVTrack* const ndaughter, Int_t pspec, Int_t nspec){\r
897 //\r
898 // Creates a mother particle\r
899 //\r
900 AliKFParticle pkfdaughter(*pdaughter, pspec);\r
901 AliKFParticle nkfdaughter(*ndaughter, nspec);\r
902 \r
903 \r
904 // Create the mother particle \r
905 AliKFParticle *m = new AliKFParticle(pkfdaughter, nkfdaughter);\r
906 // DEBUG - testing\r
907 if(TMath::Abs(kElectron) == pspec && TMath::Abs(kElectron) == nspec) m->SetMassConstraint(0, 0.001);\r
908 else if(TMath::Abs(kPiPlus) == pspec && TMath::Abs(kPiPlus) == nspec) m->SetMassConstraint(TDatabasePDG::Instance()->GetParticle(kK0Short)->Mass(), 0.);\r
909 else if(TMath::Abs(kProton) == pspec && TMath::Abs(kPiPlus) == nspec) m->SetMassConstraint(TDatabasePDG::Instance()->GetParticle(kLambda0)->Mass(), 0.);\r
910 else if(TMath::Abs(kPiPlus) == pspec && TMath::Abs(kProton) == nspec) m->SetMassConstraint(TDatabasePDG::Instance()->GetParticle(kLambda0)->Mass(), 0.);\r
911 else{\r
912 AliErrorClass("Wrong daughter ID - mass constraint can not be set");\r
913 }\r
914\r
915 AliKFVertex improvedVertex = *fPrimaryVertex;\r
916 improvedVertex += *m;\r
917 m->SetProductionVertex(improvedVertex);\r
918 \r
919 // update 15/06/2010\r
920 // mother particle will not be added to primary vertex but only to its copy \r
921 // as this confilcts with calling\r
922 // m->SetPrimaryVertex() function and\r
923 // subsequently removing the mother particle afterwards\r
924 // Source: Sergey Gorbunov\r
925\r
926 return m;\r
927}\r
928//____________________________________________________________________\r
929void AliESDv0KineCuts::SetEvent(AliESDEvent* const event){\r
930 //\r
931 // direct setter of ESD event\r
932 //\r
933 fEvent = event;\r
934 if(!fEvent){\r
935 AliErrorClass("Invalid input event pointer");\r
936 return;\r
937 }\r
938\r
939}\r
940//____________________________________________________________________\r
941void AliESDv0KineCuts::SetEvent(AliVEvent* const event){\r
942 //\r
943 // direct setter of ESD event\r
944 //\r
945 if(event)\r
946 fEvent = static_cast<AliESDEvent*>(event);\r
947 if(!fEvent){\r
948 AliErrorClass("Invalid input event pointer");\r
949 return;\r
950 }\r
951\r
952}\r
953//________________________________________________________________\r
954void AliESDv0KineCuts::SetPrimaryVertex(AliKFVertex* const v){\r
955 //\r
956 // set the primary vertex of the event\r
957 //\r
958 fPrimaryVertex = v;\r
959 if(!fPrimaryVertex){\r
960 AliErrorClass("Failed to initialize the primary vertex");\r
961 return;\r
962 }\r
963}\r
964//___________________________________________________________________\r
965void AliESDv0KineCuts::SetMode(Int_t mode, Int_t type){\r
966 //\r
967 // this function allows the user to select (prior running the 'ProcessV0' function)\r
968 // to select different approaches to V0 selection - the 'mode'\r
969 // - and -\r
970 // different systems (pp, PbPb) - 'type' \r
971 //\r
972 // To see the cut values for different modes please refer to the\r
973 // function SetCuts()\r
974 //\r
975 // Important notice: based on the parameters particular sets of cuts will\r
976 // be activated for teh V0 selection. If some additional changes to single\r
977 // cuts are needed please us the SetXXXcut function (see the header file)\r
978 // \r
979\r
980 switch(mode){\r
981 case kPurity:\r
982 fMode = kPurity; // used to obtain highest purity possible - the efficiency may be low\r
983 case kEffGamma:\r
984 fMode = kEffGamma; // used to obtain highes efficiency possible - the purity may be worse\r
985 default:\r
986 AliError("V0 selection mode not recognozed, setting 'kPurity'");\r
987 fMode = kPurity;\r
988 }\r
989\r
990 switch(type){\r
991 case kPP:\r
992 fType = kPP; // cuts optimized for low multiplicity \r
993 case kPbPb:\r
994 fType = kPbPb; // cuts optimized for high multiplicity\r
995 }\r
996 \r
997 // setup the cut values for selected mode & type\r
998 SetCuts();\r
999\r
1000}\r
1001//___________________________________________________________________\r
1002void AliESDv0KineCuts::SetMode(Int_t mode, const char* type){\r
1003 //\r
1004 // overloaded function - please see above\r
1005 // \r
1006 \r
1007 Int_t t = -1;\r
1008\r
1009 if(!strcmp("pp", type)) t = kPP;\r
1010 else if(!(strcmp("PbPb", type))) t = kPbPb;\r
1011 else{\r
1012 AliError("data type not recognized, setting 'pp'");\r
1013 t = kPP; \r
1014 }\r
1015\r
1016 SetMode(mode, t);\r
1017\r
1018}\r
1019//___________________________________________________________________\r
1020void AliESDv0KineCuts::SetCuts(){\r
1021 //\r
1022 // this funciton sets the default cut values based on the selected\r
1023 // fMode and fType.\r
1024 // please note that only the cuts that have different values than the default\r
1025 // cuts are updated here\r
1026 //\r
1027 \r
1028 // last update: 14/02/2011\r
1029 // as a very preliminary - the only change to default cuts is to apply\r
1030 // less restricting gamma conversion selection in PreselectV0() function\r
1031 \r
1032\r
1033 \r
1034}\r