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006b5f7f | 1 | /************************************************************************** |
2 | * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. * | |
3 | * * | |
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 purpose. It is * | |
13 | * provided "as is" without express or implied warranty. * | |
14 | **************************************************************************/ | |
15 | ||
ae00569a | 16 | /* $Id$ */ |
17 | ||
66e811e2 | 18 | /////////////////////////////////////////////////////////////////////////// |
006b5f7f | 19 | // Implementation of the ITS track class |
20 | // | |
21 | // Origin: Iouri Belikov, CERN, Jouri.Belikov@cern.ch | |
a9a2d814 | 22 | // dEdx analysis by: Boris Batyunya, JINR, Boris.Batiounia@cern.ch |
66e811e2 | 23 | /////////////////////////////////////////////////////////////////////////// |
006b5f7f | 24 | #include <TMath.h> |
006b5f7f | 25 | |
26 | #include "AliCluster.h" | |
58e536c5 | 27 | #include "AliESDVertex.h" |
8a84886c | 28 | #include "AliITSReconstructor.h" |
006b5f7f | 29 | #include "AliITStrackV2.h" |
f7a1cc68 | 30 | #include "AliTracker.h" |
006b5f7f | 31 | |
8602c008 | 32 | const Int_t AliITStrackV2::fgkWARN = 5; |
33 | ||
1aedd96e | 34 | ClassImp(AliITStrackV2) |
8676d691 | 35 | |
e43c066c | 36 | |
22b13da0 | 37 | //____________________________________________________________________________ |
6c94f330 | 38 | AliITStrackV2::AliITStrackV2() : AliKalmanTrack(), |
545af9ef | 39 | fCheckInvariant(kTRUE), |
22b13da0 | 40 | fdEdx(0), |
83d73500 | 41 | fESDtrack(0) |
e43c066c | 42 | { |
ae00569a | 43 | for(Int_t i=0; i<2*AliITSgeomTGeo::kNLayers; i++) {fIndex[i]=-1; fModule[i]=-1;} |
44 | for(Int_t i=0; i<4; i++) fdEdxSample[i]=0; | |
e43c066c | 45 | } |
46 | ||
83d73500 | 47 | |
83d73500 | 48 | //____________________________________________________________________________ |
763bdf3e | 49 | AliITStrackV2::AliITStrackV2(AliESDtrack& t,Bool_t c): |
6c94f330 | 50 | AliKalmanTrack(), |
545af9ef | 51 | fCheckInvariant(kTRUE), |
6c94f330 | 52 | fdEdx(t.GetITSsignal()), |
53 | fESDtrack(&t) | |
54 | { | |
83d73500 | 55 | //------------------------------------------------------------------ |
67c3dcbe | 56 | // Conversion ESD track -> ITS track. |
57 | // If c==kTRUE, create the ITS track out of the constrained params. | |
83d73500 | 58 | //------------------------------------------------------------------ |
6c94f330 | 59 | const AliExternalTrackParam *par=&t; |
60 | if (c) { | |
6c4ef2ed | 61 | par=t.GetConstrainedParam(); |
763bdf3e | 62 | if (!par) AliError("AliITStrackV2: conversion failed !\n"); |
6c94f330 | 63 | } |
64 | Set(par->GetX(),par->GetAlpha(),par->GetParameter(),par->GetCovariance()); | |
65 | ||
83d73500 | 66 | SetLabel(t.GetLabel()); |
67 | SetMass(t.GetMass()); | |
6c94f330 | 68 | SetNumberOfClusters(t.GetITSclusters(fIndex)); |
006b5f7f | 69 | |
83d73500 | 70 | if (t.GetStatus()&AliESDtrack::kTIME) { |
71 | StartTimeIntegral(); | |
72 | Double_t times[10]; t.GetIntegratedTimes(times); SetIntegratedTimes(times); | |
73 | SetIntegratedLength(t.GetIntegratedLength()); | |
74 | } | |
e43c066c | 75 | |
68b8060b | 76 | for(Int_t i=0; i<4; i++) fdEdxSample[i]=0; |
006b5f7f | 77 | } |
78 | ||
7ac23097 | 79 | //____________________________________________________________________________ |
80 | void AliITStrackV2::ResetClusters() { | |
81 | //------------------------------------------------------------------ | |
82 | // Reset the array of attached clusters. | |
83 | //------------------------------------------------------------------ | |
84 | for (Int_t i=0; i<2*AliITSgeomTGeo::kNLayers; i++) fIndex[i]=-1; | |
85 | SetChi2(0.); | |
86 | SetNumberOfClusters(0); | |
87 | } | |
88 | ||
09cf9d66 | 89 | //____________________________________________________________________________ |
15dd636f | 90 | void AliITStrackV2::UpdateESDtrack(ULong_t flags) const { |
09cf9d66 | 91 | // Update track params |
83d73500 | 92 | fESDtrack->UpdateTrackParams(this,flags); |
ae00569a | 93 | // copy the module indices |
94 | for(Int_t i=0;i<12;i++) { | |
95 | // printf(" %d\n",GetModuleIndex(i)); | |
96 | fESDtrack->SetITSModuleIndex(i,GetModuleIndex(i)); | |
97 | } | |
09cf9d66 | 98 | // copy the 4 dedx samples |
99 | Double_t sdedx[4]={0.,0.,0.,0.}; | |
100 | for(Int_t i=0; i<4; i++) sdedx[i]=fdEdxSample[i]; | |
101 | fESDtrack->SetITSdEdxSamples(sdedx); | |
83d73500 | 102 | } |
103 | ||
006b5f7f | 104 | //____________________________________________________________________________ |
6c94f330 | 105 | AliITStrackV2::AliITStrackV2(const AliITStrackV2& t) : |
106 | AliKalmanTrack(t), | |
545af9ef | 107 | fCheckInvariant(t.fCheckInvariant), |
6c94f330 | 108 | fdEdx(t.fdEdx), |
109 | fESDtrack(t.fESDtrack) | |
110 | { | |
006b5f7f | 111 | //------------------------------------------------------------------ |
112 | //Copy constructor | |
113 | //------------------------------------------------------------------ | |
ef7253ac | 114 | Int_t i; |
ef7253ac | 115 | for (i=0; i<4; i++) fdEdxSample[i]=t.fdEdxSample[i]; |
ae00569a | 116 | for (i=0; i<2*AliITSgeomTGeo::GetNLayers(); i++) { |
117 | fIndex[i]=t.fIndex[i]; | |
118 | fModule[i]=t.fModule[i]; | |
119 | } | |
006b5f7f | 120 | } |
a9a2d814 | 121 | |
006b5f7f | 122 | //_____________________________________________________________________________ |
123 | Int_t AliITStrackV2::Compare(const TObject *o) const { | |
124 | //----------------------------------------------------------------- | |
125 | // This function compares tracks according to the their curvature | |
126 | //----------------------------------------------------------------- | |
7f6ddf58 | 127 | AliITStrackV2 *t=(AliITStrackV2*)o; |
6c23ffed | 128 | //Double_t co=OneOverPt(); |
129 | //Double_t c =OneOverPt(); | |
15dd636f | 130 | Double_t co=t->GetSigmaY2()*t->GetSigmaZ2(); |
131 | Double_t c =GetSigmaY2()*GetSigmaZ2(); | |
006b5f7f | 132 | if (c>co) return 1; |
133 | else if (c<co) return -1; | |
134 | return 0; | |
135 | } | |
136 | ||
006b5f7f | 137 | //____________________________________________________________________________ |
6c94f330 | 138 | Bool_t |
139 | AliITStrackV2::PropagateToVertex(const AliESDVertex *v,Double_t d,Double_t x0) | |
140 | { | |
006b5f7f | 141 | //------------------------------------------------------------------ |
142 | //This function propagates a track to the minimal distance from the origin | |
6c94f330 | 143 | //------------------------------------------------------------------ |
144 | Double_t bz=GetBz(); | |
e50912db | 145 | if (PropagateToDCA(v,bz,kVeryBig)) { |
146 | Double_t xOverX0,xTimesRho; | |
147 | xOverX0 = d; xTimesRho = d*x0; | |
148 | if (CorrectForMeanMaterial(xOverX0,xTimesRho,kTRUE)) return kTRUE; | |
149 | } | |
6c94f330 | 150 | return kFALSE; |
006b5f7f | 151 | } |
152 | ||
153 | //____________________________________________________________________________ | |
6c94f330 | 154 | Bool_t AliITStrackV2:: |
e50912db | 155 | GetGlobalXYZat(Double_t xloc, Double_t &x, Double_t &y, Double_t &z) const { |
006b5f7f | 156 | //------------------------------------------------------------------ |
157 | //This function returns a track position in the global system | |
158 | //------------------------------------------------------------------ | |
6c94f330 | 159 | Double_t r[3]; |
f7a1cc68 | 160 | Bool_t rc=GetXYZAt(xloc, GetBz(), r); |
6c94f330 | 161 | x=r[0]; y=r[1]; z=r[2]; |
162 | return rc; | |
006b5f7f | 163 | } |
164 | ||
165 | //_____________________________________________________________________________ | |
6c94f330 | 166 | Double_t AliITStrackV2::GetPredictedChi2(const AliCluster *c) const { |
006b5f7f | 167 | //----------------------------------------------------------------- |
168 | // This function calculates a predicted chi2 increment. | |
169 | //----------------------------------------------------------------- | |
6c94f330 | 170 | Double_t p[2]={c->GetY(), c->GetZ()}; |
171 | Double_t cov[3]={c->GetSigmaY2(), 0., c->GetSigmaZ2()}; | |
172 | return AliExternalTrackParam::GetPredictedChi2(p,cov); | |
a9a2d814 | 173 | } |
174 | ||
175 | //____________________________________________________________________________ | |
6c94f330 | 176 | Bool_t AliITStrackV2::PropagateTo(Double_t xk, Double_t d, Double_t x0) { |
006b5f7f | 177 | //------------------------------------------------------------------ |
178 | //This function propagates a track | |
179 | //------------------------------------------------------------------ | |
afd25725 | 180 | |
6c94f330 | 181 | Double_t oldX=GetX(), oldY=GetY(), oldZ=GetZ(); |
006b5f7f | 182 | |
1defa402 | 183 | //Double_t bz=GetBz(); |
184 | //if (!AliExternalTrackParam::PropagateTo(xk,bz)) return kFALSE; | |
185 | Double_t b[3]; GetBxByBz(b); | |
186 | if (!AliExternalTrackParam::PropagateToBxByBz(xk,b)) return kFALSE; | |
e50912db | 187 | Double_t xOverX0,xTimesRho; |
188 | xOverX0 = d; xTimesRho = d*x0; | |
189 | if (!CorrectForMeanMaterial(xOverX0,xTimesRho,kTRUE)) return kFALSE; | |
006b5f7f | 190 | |
dd44614b | 191 | Double_t x=GetX(), y=GetY(), z=GetZ(); |
6c94f330 | 192 | if (IsStartedTimeIntegral() && x>oldX) { |
193 | Double_t l2 = (x-oldX)*(x-oldX) + (y-oldY)*(y-oldY) + (z-oldZ)*(z-oldZ); | |
f29dbb4b | 194 | AddTimeStep(TMath::Sqrt(l2)); |
195 | } | |
f29dbb4b | 196 | |
6c94f330 | 197 | return kTRUE; |
006b5f7f | 198 | } |
199 | ||
afd25725 | 200 | //____________________________________________________________________________ |
db355ee7 | 201 | Bool_t AliITStrackV2::PropagateToTGeo(Double_t xToGo, Int_t nstep, Double_t &xOverX0, Double_t &xTimesRho, Bool_t addTime) { |
afd25725 | 202 | //------------------------------------------------------------------- |
203 | // Propagates the track to a reference plane x=xToGo in n steps. | |
204 | // These n steps are only used to take into account the curvature. | |
205 | // The material is calculated with TGeo. (L.Gaudichet) | |
206 | //------------------------------------------------------------------- | |
207 | ||
208 | Double_t startx = GetX(), starty = GetY(), startz = GetZ(); | |
209 | Double_t sign = (startx<xToGo) ? -1.:1.; | |
210 | Double_t step = (xToGo-startx)/TMath::Abs(nstep); | |
211 | ||
1defa402 | 212 | Double_t start[3], end[3], mparam[7]; |
213 | //Double_t bz = GetBz(); | |
214 | Double_t b[3]; GetBxByBz(b); | |
215 | Double_t bz = b[2]; | |
216 | ||
afd25725 | 217 | Double_t x = startx; |
218 | ||
219 | for (Int_t i=0; i<nstep; i++) { | |
220 | ||
221 | GetXYZ(start); //starting global position | |
222 | x += step; | |
223 | if (!GetXYZAt(x, bz, end)) return kFALSE; | |
1defa402 | 224 | //if (!AliExternalTrackParam::PropagateTo(x, bz)) return kFALSE; |
225 | if (!AliExternalTrackParam::PropagateToBxByBz(x, b)) return kFALSE; | |
afd25725 | 226 | AliTracker::MeanMaterialBudget(start, end, mparam); |
8fc9f3dc | 227 | xTimesRho = sign*mparam[4]*mparam[0]; |
228 | xOverX0 = mparam[1]; | |
afd25725 | 229 | if (mparam[1]<900000) { |
afd25725 | 230 | if (!AliExternalTrackParam::CorrectForMeanMaterial(xOverX0, |
8fc9f3dc | 231 | xTimesRho,GetMass())) return kFALSE; |
232 | } else { // this happens when MeanMaterialBudget cannot cross a boundary | |
233 | return kFALSE; | |
afd25725 | 234 | } |
235 | } | |
236 | ||
db355ee7 | 237 | if (addTime && IsStartedTimeIntegral() && GetX()>startx) { |
afd25725 | 238 | Double_t l2 = ( (GetX()-startx)*(GetX()-startx) + |
239 | (GetY()-starty)*(GetY()-starty) + | |
240 | (GetZ()-startz)*(GetZ()-startz) ); | |
241 | AddTimeStep(TMath::Sqrt(l2)); | |
242 | } | |
243 | ||
244 | return kTRUE; | |
245 | } | |
246 | ||
006b5f7f | 247 | //____________________________________________________________________________ |
6c94f330 | 248 | Bool_t AliITStrackV2::Update(const AliCluster* c, Double_t chi2, Int_t index) |
249 | { | |
006b5f7f | 250 | //------------------------------------------------------------------ |
251 | //This function updates track parameters | |
252 | //------------------------------------------------------------------ | |
6c94f330 | 253 | Double_t p[2]={c->GetY(), c->GetZ()}; |
d9ead1a0 | 254 | Double_t cov[3]={c->GetSigmaY2(), c->GetSigmaYZ(), c->GetSigmaZ2()}; |
006b5f7f | 255 | |
6c94f330 | 256 | if (!AliExternalTrackParam::Update(p,cov)) return kFALSE; |
006b5f7f | 257 | |
28d5b13d | 258 | Int_t n=GetNumberOfClusters(); |
006b5f7f | 259 | if (!Invariant()) { |
28d5b13d | 260 | if (n>fgkWARN) AliWarning("Wrong invariant !"); |
6c94f330 | 261 | return kFALSE; |
006b5f7f | 262 | } |
263 | ||
6c94f330 | 264 | if (chi2<0) return kTRUE; |
67c3dcbe | 265 | |
b5205c90 | 266 | // fill residuals for ITS+TPC tracks |
badb951a | 267 | if (fESDtrack) { |
268 | if (fESDtrack->GetStatus()&AliESDtrack::kTPCin) { | |
269 | AliTracker::FillResiduals(this,p,cov,c->GetVolumeId()); | |
270 | } | |
b5205c90 | 271 | } |
150f264c | 272 | |
006b5f7f | 273 | fIndex[n]=index; |
274 | SetNumberOfClusters(n+1); | |
275 | SetChi2(GetChi2()+chi2); | |
276 | ||
6c94f330 | 277 | return kTRUE; |
006b5f7f | 278 | } |
279 | ||
6c94f330 | 280 | Bool_t AliITStrackV2::Invariant() const { |
006b5f7f | 281 | //------------------------------------------------------------------ |
282 | // This function is for debugging purpose only | |
283 | //------------------------------------------------------------------ | |
545af9ef | 284 | if(!fCheckInvariant) return kTRUE; |
285 | ||
7f6ddf58 | 286 | Int_t n=GetNumberOfClusters(); |
6c94f330 | 287 | |
8a84886c | 288 | // take into account the misalignment error |
289 | Float_t maxMisalErrY2=0,maxMisalErrZ2=0; | |
290 | for (Int_t lay=0; lay<AliITSgeomTGeo::kNLayers; lay++) { | |
d9ead1a0 | 291 | maxMisalErrY2 = TMath::Max(maxMisalErrY2,AliITSReconstructor::GetRecoParam()->GetClusterMisalErrorY(lay,GetBz())); |
292 | maxMisalErrZ2 = TMath::Max(maxMisalErrZ2,AliITSReconstructor::GetRecoParam()->GetClusterMisalErrorZ(lay,GetBz())); | |
8a84886c | 293 | } |
294 | maxMisalErrY2 *= maxMisalErrY2; | |
295 | maxMisalErrZ2 *= maxMisalErrZ2; | |
296 | // this is because when we reset before refitting, we multiply the | |
297 | // matrix by 10 | |
298 | maxMisalErrY2 *= 10.; | |
299 | maxMisalErrZ2 *= 10.; | |
300 | ||
6c94f330 | 301 | Double_t sP2=GetParameter()[2]; |
302 | if (TMath::Abs(sP2) >= kAlmost1){ | |
8602c008 | 303 | if (n>fgkWARN) Warning("Invariant","fP2=%f\n",sP2); |
6c94f330 | 304 | return kFALSE; |
a9a2d814 | 305 | } |
6c94f330 | 306 | Double_t sC00=GetCovariance()[0]; |
8a84886c | 307 | if (sC00<=0 || sC00>(9.+maxMisalErrY2)) { |
8602c008 | 308 | if (n>fgkWARN) Warning("Invariant","fC00=%f\n",sC00); |
6c94f330 | 309 | return kFALSE; |
a9a2d814 | 310 | } |
6c94f330 | 311 | Double_t sC11=GetCovariance()[2]; |
8a84886c | 312 | if (sC11<=0 || sC11>(9.+maxMisalErrZ2)) { |
8602c008 | 313 | if (n>fgkWARN) Warning("Invariant","fC11=%f\n",sC11); |
6c94f330 | 314 | return kFALSE; |
a9a2d814 | 315 | } |
6c94f330 | 316 | Double_t sC22=GetCovariance()[5]; |
317 | if (sC22<=0 || sC22>1.) { | |
8602c008 | 318 | if (n>fgkWARN) Warning("Invariant","fC22=%f\n",sC22); |
6c94f330 | 319 | return kFALSE; |
a9a2d814 | 320 | } |
6c94f330 | 321 | Double_t sC33=GetCovariance()[9]; |
322 | if (sC33<=0 || sC33>1.) { | |
8602c008 | 323 | if (n>fgkWARN) Warning("Invariant","fC33=%f\n",sC33); |
6c94f330 | 324 | return kFALSE; |
a9a2d814 | 325 | } |
6c94f330 | 326 | Double_t sC44=GetCovariance()[14]; |
327 | if (sC44<=0 /*|| sC44>6e-5*/) { | |
8602c008 | 328 | if (n>fgkWARN) Warning("Invariant","fC44=%f\n",sC44); |
6c94f330 | 329 | return kFALSE; |
14825d5a | 330 | } |
6c94f330 | 331 | |
332 | return kTRUE; | |
006b5f7f | 333 | } |
334 | ||
335 | //____________________________________________________________________________ | |
6c94f330 | 336 | Bool_t AliITStrackV2::Propagate(Double_t alp,Double_t xk) { |
006b5f7f | 337 | //------------------------------------------------------------------ |
338 | //This function propagates a track | |
339 | //------------------------------------------------------------------ | |
1defa402 | 340 | //Double_t bz=GetBz(); |
341 | //if (!AliExternalTrackParam::Propagate(alp,xk,bz)) return kFALSE; | |
342 | Double_t b[3]; GetBxByBz(b); | |
343 | if (!AliExternalTrackParam::PropagateBxByBz(alp,xk,b)) return kFALSE; | |
006b5f7f | 344 | |
006b5f7f | 345 | if (!Invariant()) { |
8a84886c | 346 | Int_t n=GetNumberOfClusters(); |
347 | if (n>fgkWARN) AliWarning("Wrong invariant !"); | |
348 | return kFALSE; | |
791f9a2a | 349 | } |
350 | ||
6c94f330 | 351 | return kTRUE; |
a9a2d814 | 352 | } |
006b5f7f | 353 | |
afd25725 | 354 | Bool_t AliITStrackV2::MeanBudgetToPrimVertex(Double_t xyz[3], Double_t step, Double_t &d) const { |
355 | ||
356 | //------------------------------------------------------------------- | |
357 | // Get the mean material budget between the actual point and the | |
358 | // primary vertex. (L.Gaudichet) | |
359 | //------------------------------------------------------------------- | |
360 | ||
361 | Double_t cs=TMath::Cos(GetAlpha()), sn=TMath::Sin(GetAlpha()); | |
362 | Double_t vertexX = xyz[0]*cs + xyz[1]*sn; | |
363 | ||
364 | Int_t nstep = Int_t((GetX()-vertexX)/step); | |
365 | if (nstep<1) nstep = 1; | |
366 | step = (GetX()-vertexX)/nstep; | |
367 | ||
c7719399 | 368 | // Double_t mparam[7], densMean=0, radLength=0, length=0; |
369 | Double_t mparam[7]; | |
afd25725 | 370 | Double_t p1[3], p2[3], x = GetX(), bz = GetBz(); |
371 | GetXYZ(p1); | |
372 | ||
373 | d=0.; | |
374 | ||
375 | for (Int_t i=0; i<nstep; i++) { | |
376 | x += step; | |
377 | if (!GetXYZAt(x, bz, p2)) return kFALSE; | |
378 | AliTracker::MeanMaterialBudget(p1, p2, mparam); | |
379 | if (mparam[1]>900000) return kFALSE; | |
380 | d += mparam[1]; | |
381 | ||
382 | p1[0] = p2[0]; | |
383 | p1[1] = p2[1]; | |
384 | p1[2] = p2[2]; | |
385 | } | |
386 | ||
387 | return kTRUE; | |
388 | } | |
389 | ||
6c94f330 | 390 | Bool_t AliITStrackV2::Improve(Double_t x0,Double_t xyz[3],Double_t ers[3]) { |
babd135a | 391 | //------------------------------------------------------------------ |
6c94f330 | 392 | //This function improves angular track parameters |
babd135a | 393 | //------------------------------------------------------------------ |
86be8934 | 394 | //Store the initail track parameters |
395 | ||
86be8934 | 396 | Double_t x = GetX(); |
397 | Double_t alpha = GetAlpha(); | |
398 | Double_t par[] = {GetY(),GetZ(),GetSnp(),GetTgl(),GetSigned1Pt()}; | |
399 | Double_t cov[] = { | |
400 | GetSigmaY2(), | |
401 | GetSigmaZY(), | |
402 | GetSigmaZ2(), | |
403 | GetSigmaSnpY(), | |
404 | GetSigmaSnpZ(), | |
405 | GetSigmaSnp2(), | |
406 | GetSigmaTglY(), | |
407 | GetSigmaTglZ(), | |
408 | GetSigmaTglSnp(), | |
409 | GetSigmaTgl2(), | |
410 | GetSigma1PtY(), | |
411 | GetSigma1PtZ(), | |
412 | GetSigma1PtSnp(), | |
413 | GetSigma1PtTgl(), | |
414 | GetSigma1Pt2() | |
415 | }; | |
416 | ||
417 | ||
6c94f330 | 418 | Double_t cs=TMath::Cos(GetAlpha()), sn=TMath::Sin(GetAlpha()); |
419 | //Double_t xv = xyz[0]*cs + xyz[1]*sn; // vertex | |
420 | Double_t yv =-xyz[0]*sn + xyz[1]*cs; // in the | |
421 | Double_t zv = xyz[2]; // local frame | |
babd135a | 422 | |
86be8934 | 423 | Double_t dy = par[0] - yv, dz = par[1] - zv; |
6c94f330 | 424 | Double_t r2=GetX()*GetX() + dy*dy; |
6c23ffed | 425 | Double_t p2=(1.+ GetTgl()*GetTgl())/(GetSigned1Pt()*GetSigned1Pt()); |
a9a2d814 | 426 | Double_t beta2=p2/(p2 + GetMass()*GetMass()); |
427 | x0*=TMath::Sqrt((1.+ GetTgl()*GetTgl())/(1.- GetSnp()*GetSnp())); | |
8676d691 | 428 | Double_t theta2=14.1*14.1/(beta2*p2*1e6)*x0; |
429 | //Double_t theta2=1.0259e-6*14*14/28/(beta2*p2)*x0*9.36*2.33; | |
6c94f330 | 430 | |
431 | Double_t cnv=GetBz()*kB2C; | |
a9a2d814 | 432 | { |
6c94f330 | 433 | Double_t dummy = 4/r2 - GetC()*GetC(); |
434 | if (dummy < 0) return kFALSE; | |
435 | Double_t parp = 0.5*(GetC()*GetX() + dy*TMath::Sqrt(dummy)); | |
bfd20868 | 436 | Double_t sigma2p = theta2*(1.-GetSnp())*(1.+GetSnp())*(1. + GetTgl()*GetTgl()); |
437 | Double_t ovSqr2 = 1./TMath::Sqrt(r2); | |
438 | Double_t tfact = ovSqr2*(1.-dy*ovSqr2)*(1.+dy*ovSqr2); | |
86be8934 | 439 | sigma2p += cov[0]*tfact*tfact; |
6c94f330 | 440 | sigma2p += ers[1]*ers[1]/r2; |
86be8934 | 441 | sigma2p += 0.25*cov[14]*cnv*cnv*GetX()*GetX(); |
442 | Double_t eps2p=sigma2p/(cov[5] + sigma2p); | |
443 | par[0] += cov[3]/(cov[5] + sigma2p)*(parp - GetSnp()); | |
444 | par[2] = eps2p*GetSnp() + (1 - eps2p)*parp; | |
445 | cov[5] *= eps2p; | |
446 | cov[3] *= eps2p; | |
a9a2d814 | 447 | } |
448 | { | |
6c94f330 | 449 | Double_t parl=0.5*GetC()*dz/TMath::ASin(0.5*GetC()*TMath::Sqrt(r2)); |
450 | Double_t sigma2l=theta2; | |
86be8934 | 451 | sigma2l += cov[2]/r2 + cov[0]*dy*dy*dz*dz/(r2*r2*r2); |
6c94f330 | 452 | sigma2l += ers[2]*ers[2]/r2; |
86be8934 | 453 | Double_t eps2l = sigma2l/(cov[9] + sigma2l); |
454 | par[1] += cov[7 ]/(cov[9] + sigma2l)*(parl - par[3]); | |
455 | par[4] += cov[13]/(cov[9] + sigma2l)*(parl - par[3]); | |
456 | par[3] = eps2l*par[3] + (1-eps2l)*parl; | |
457 | cov[9] *= eps2l; | |
458 | cov[13]*= eps2l; | |
459 | cov[7] *= eps2l; | |
a9a2d814 | 460 | } |
86be8934 | 461 | |
462 | Set(x,alpha,par,cov); | |
463 | ||
6c94f330 | 464 | if (!Invariant()) return kFALSE; |
14825d5a | 465 | |
6c94f330 | 466 | return kTRUE; |
14825d5a | 467 | } |
23efe5f1 | 468 | |
469 | void AliITStrackV2::CookdEdx(Double_t low, Double_t up) { | |
470 | //----------------------------------------------------------------- | |
a9a2d814 | 471 | // This function calculates dE/dX within the "low" and "up" cuts. |
472 | // Origin: Boris Batyunya, JINR, Boris.Batiounia@cern.ch | |
09cf9d66 | 473 | // Updated: F. Prino 8-June-2009 |
23efe5f1 | 474 | //----------------------------------------------------------------- |
09cf9d66 | 475 | // The cluster order is: SDD-1, SDD-2, SSD-1, SSD-2 |
c0dd5278 | 476 | |
c0dd5278 | 477 | Int_t nc=0; |
09cf9d66 | 478 | Float_t dedx[4]; |
479 | for (Int_t il=0; il<4; il++) { // count good (>0) dE/dx values | |
480 | if(fdEdxSample[il]>0.){ | |
481 | dedx[nc]= fdEdxSample[il]; | |
482 | nc++; | |
483 | } | |
484 | } | |
485 | if(nc<1){ | |
486 | SetdEdx(0.); | |
487 | return; | |
c0dd5278 | 488 | } |
23efe5f1 | 489 | |
09cf9d66 | 490 | Int_t swap; // sort in ascending order |
23efe5f1 | 491 | do { |
492 | swap=0; | |
09cf9d66 | 493 | for (Int_t i=0; i<nc-1; i++) { |
494 | if (dedx[i]<=dedx[i+1]) continue; | |
495 | Float_t tmp=dedx[i]; | |
496 | dedx[i]=dedx[i+1]; | |
497 | dedx[i+1]=tmp; | |
23efe5f1 | 498 | swap++; |
499 | } | |
500 | } while (swap); | |
501 | ||
23efe5f1 | 502 | |
09cf9d66 | 503 | Double_t nl=low*nc, nu =up*nc; |
504 | Float_t sumamp = 0; | |
505 | Float_t sumweight =0; | |
506 | for (Int_t i=0; i<nc; i++) { | |
507 | Float_t weight =1; | |
508 | if (i<nl+0.1) weight = TMath::Max(1.-(nl-i),0.); | |
509 | if (i>nu-1) weight = TMath::Max(nu-i,0.); | |
510 | sumamp+= dedx[i]*weight; | |
511 | sumweight+=weight; | |
512 | } | |
513 | SetdEdx(sumamp/sumweight); | |
23efe5f1 | 514 | } |
c7bafca9 | 515 | |
8602c008 | 516 | //____________________________________________________________________________ |
517 | Bool_t AliITStrackV2:: | |
e50912db | 518 | GetPhiZat(Double_t r, Double_t &phi, Double_t &z) const { |
519 | //------------------------------------------------------------------ | |
520 | // This function returns the global cylindrical (phi,z) of the track | |
521 | // position estimated at the radius r. | |
522 | // The track curvature is neglected. | |
523 | //------------------------------------------------------------------ | |
524 | Double_t d=GetD(0.,0.); | |
bc02d571 | 525 | if (TMath::Abs(d) > r) { |
526 | if (r>1e-1) return kFALSE; | |
527 | r = TMath::Abs(d); | |
528 | } | |
e50912db | 529 | |
530 | Double_t rcurr=TMath::Sqrt(GetX()*GetX() + GetY()*GetY()); | |
494a930c | 531 | if (TMath::Abs(d) > rcurr) return kFALSE; |
532 | Double_t globXYZcurr[3]; GetXYZ(globXYZcurr); | |
533 | Double_t phicurr=TMath::ATan2(globXYZcurr[1],globXYZcurr[0]); | |
e50912db | 534 | |
2089d338 | 535 | if (GetX()>=0.) { |
536 | phi=phicurr+TMath::ASin(d/r)-TMath::ASin(d/rcurr); | |
537 | } else { | |
538 | phi=phicurr+TMath::ASin(d/r)+TMath::ASin(d/rcurr)-TMath::Pi(); | |
539 | } | |
540 | ||
494a930c | 541 | // return a phi in [0,2pi[ |
542 | if (phi<0.) phi+=2.*TMath::Pi(); | |
543 | else if (phi>=2.*TMath::Pi()) phi-=2.*TMath::Pi(); | |
c7de5c65 | 544 | z=GetZ()+GetTgl()*(TMath::Sqrt((r-d)*(r+d))-TMath::Sqrt((rcurr-d)*(rcurr+d))); |
e50912db | 545 | return kTRUE; |
546 | } | |
547 | //____________________________________________________________________________ | |
548 | Bool_t AliITStrackV2:: | |
549 | GetLocalXat(Double_t r,Double_t &xloc) const { | |
8602c008 | 550 | //------------------------------------------------------------------ |
e50912db | 551 | // This function returns the local x of the track |
552 | // position estimated at the radius r. | |
8602c008 | 553 | // The track curvature is neglected. |
554 | //------------------------------------------------------------------ | |
555 | Double_t d=GetD(0.,0.); | |
6a14afad | 556 | if (TMath::Abs(d) > r) { |
557 | if (r>1e-1) return kFALSE; | |
558 | r = TMath::Abs(d); | |
559 | } | |
8602c008 | 560 | |
e50912db | 561 | Double_t rcurr=TMath::Sqrt(GetX()*GetX() + GetY()*GetY()); |
494a930c | 562 | Double_t globXYZcurr[3]; GetXYZ(globXYZcurr); |
563 | Double_t phicurr=TMath::ATan2(globXYZcurr[1],globXYZcurr[0]); | |
2089d338 | 564 | Double_t phi; |
565 | if (GetX()>=0.) { | |
566 | phi=phicurr+TMath::ASin(d/r)-TMath::ASin(d/rcurr); | |
567 | } else { | |
568 | phi=phicurr+TMath::ASin(d/r)+TMath::ASin(d/rcurr)-TMath::Pi(); | |
569 | } | |
8602c008 | 570 | |
e50912db | 571 | xloc=r*(TMath::Cos(phi)*TMath::Cos(GetAlpha()) |
572 | +TMath::Sin(phi)*TMath::Sin(GetAlpha())); | |
8602c008 | 573 | |
574 | return kTRUE; | |
575 | } |