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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 | ||
16 | //------------------------------------------------------------------------- | |
17 | // Implementation of the ITS track class | |
18 | // | |
19 | // Origin: Iouri Belikov, CERN, Jouri.Belikov@cern.ch | |
a9a2d814 | 20 | // dEdx analysis by: Boris Batyunya, JINR, Boris.Batiounia@cern.ch |
006b5f7f | 21 | //------------------------------------------------------------------------- |
22 | ||
23 | #include <TMatrixD.h> | |
24 | ||
25 | #include <TMath.h> | |
006b5f7f | 26 | |
27 | #include "AliCluster.h" | |
e43c066c | 28 | #include "AliTPCtrack.h" |
83d73500 | 29 | #include "AliESDtrack.h" |
006b5f7f | 30 | #include "AliITStrackV2.h" |
31 | ||
1aedd96e | 32 | ClassImp(AliITStrackV2) |
8676d691 | 33 | |
e43c066c | 34 | const Int_t kWARN=5; |
35 | ||
22b13da0 | 36 | //____________________________________________________________________________ |
e6ba4672 | 37 | AliITStrackV2::AliITStrackV2():AliKalmanTrack(), |
22b13da0 | 38 | fX(0), |
39 | fAlpha(0), | |
40 | fdEdx(0), | |
41 | fP0(0), | |
42 | fP1(0), | |
43 | fP2(0), | |
44 | fP3(0), | |
45 | fP4(0), | |
46 | fC00(0), | |
47 | fC10(0), | |
48 | fC11(0), | |
49 | fC20(0), | |
50 | fC21(0), | |
51 | fC22(0), | |
52 | fC30(0), | |
53 | fC31(0), | |
54 | fC32(0), | |
55 | fC33(0), | |
56 | fC40(0), | |
57 | fC41(0), | |
58 | fC42(0), | |
59 | fC43(0), | |
83d73500 | 60 | fC44(0), |
babd135a | 61 | fNUsed(0), |
62 | fNSkipped(0), | |
e43c066c | 63 | fNDeadZone(0), |
64 | fDeadZoneProbability(0), | |
65 | fReconstructed(kFALSE), | |
66 | fConstrain(kFALSE), | |
83d73500 | 67 | fESDtrack(0) |
e43c066c | 68 | { |
69 | for(Int_t i=0; i<kMaxLayer; i++) {fIndex[i]=0;fClIndex[i]=-1;} | |
70 | for(Int_t i=0; i<4; i++) fdEdxSample[i]=0; | |
71 | for(Int_t i=0; i<6; i++) { fNy[i]=0; fNz[i]=0; fNormQ[i]=0; fNormChi2[i]=1000;} | |
72 | for(Int_t i=0; i<12; i++) {fDy[i]=0; fDz[i]=0; fSigmaY[i]=0; fSigmaZ[i]=0; fChi2MIP[i]=0;} | |
73 | fD[0]=0; fD[1]=0; | |
74 | fExpQ=40; | |
75 | fdEdxMismatch=0; | |
76 | fChi22=0; | |
77 | } | |
78 | ||
79 | //____________________________________________________________________________ | |
80 | AliITStrackV2::AliITStrackV2(const AliTPCtrack& t) throw (const Char_t *) : | |
81 | AliKalmanTrack(t) { | |
1aedd96e | 82 | //------------------------------------------------------------------ |
e43c066c | 83 | //Conversion TPC track -> ITS track |
1aedd96e | 84 | //------------------------------------------------------------------ |
e43c066c | 85 | SetChi2(0.); |
86 | SetNumberOfClusters(0); | |
87 | ||
88 | fdEdx = t.GetdEdx(); | |
89 | SetMass(t.GetMass()); | |
90 | ||
91 | fAlpha = t.GetAlpha(); | |
92 | if (fAlpha < -TMath::Pi()) fAlpha += 2*TMath::Pi(); | |
93 | else if (fAlpha >= TMath::Pi()) fAlpha -= 2*TMath::Pi(); | |
94 | ||
95 | //Conversion of the track parameters | |
96 | Double_t x,p[5]; t.GetExternalParameters(x,p); | |
97 | fX=x; x=GetConvConst(); | |
98 | fP0=p[0]; | |
99 | fP1=p[1]; | |
100 | fP2=p[2]; | |
101 | fP3=p[3]; | |
102 | fP4=p[4]/x; | |
103 | ||
104 | //Conversion of the covariance matrix | |
105 | Double_t c[15]; t.GetExternalCovariance(c); | |
106 | ||
107 | fC00=c[0 ]; | |
108 | fC10=c[1 ]; fC11=c[2 ]; | |
109 | fC20=c[3 ]; fC21=c[4 ]; fC22=c[5 ]; | |
110 | fC30=c[6 ]; fC31=c[7 ]; fC32=c[8 ]; fC33=c[9 ]; | |
111 | fC40=c[10]/x; fC41=c[11]/x; fC42=c[12]/x; fC43=c[13]/x; fC44=c[14]/x/x; | |
112 | ||
113 | for(Int_t i=0; i<6; i++) { fNy[i]=0; fNz[i]=0; fNormQ[i]=0; fNormChi2[i]=1000;} | |
114 | for(Int_t i=0; i<12; i++) {fDy[i]=0; fDz[i]=0; fSigmaY[i]=0; fSigmaZ[i]=0; } | |
115 | fConstrain=kFALSE; | |
116 | // | |
117 | if (!Invariant()) throw "AliITStrackV2: conversion failed !\n"; | |
118 | ||
22b13da0 | 119 | } |
83d73500 | 120 | |
83d73500 | 121 | //____________________________________________________________________________ |
67c3dcbe | 122 | AliITStrackV2::AliITStrackV2(AliESDtrack& t,Bool_t c) throw (const Char_t *) : |
83d73500 | 123 | AliKalmanTrack() { |
124 | //------------------------------------------------------------------ | |
67c3dcbe | 125 | // Conversion ESD track -> ITS track. |
126 | // If c==kTRUE, create the ITS track out of the constrained params. | |
83d73500 | 127 | //------------------------------------------------------------------ |
128 | SetNumberOfClusters(t.GetITSclusters(fIndex)); | |
129 | SetLabel(t.GetLabel()); | |
130 | SetMass(t.GetMass()); | |
e43c066c | 131 | // |
132 | // | |
83d73500 | 133 | |
134 | fdEdx=t.GetITSsignal(); | |
135 | fAlpha = t.GetAlpha(); | |
136 | if (fAlpha < -TMath::Pi()) fAlpha += 2*TMath::Pi(); | |
137 | else if (fAlpha >= TMath::Pi()) fAlpha -= 2*TMath::Pi(); | |
138 | ||
9b280d80 | 139 | //Conversion of the track parameters |
67c3dcbe | 140 | Double_t x,p[5]; |
141 | if (c) t.GetConstrainedExternalParameters(x,p); | |
142 | else t.GetExternalParameters(x,p); | |
9b280d80 | 143 | fX=x; x=GetConvConst(); |
006b5f7f | 144 | fP0=p[0]; |
145 | fP1=p[1]; | |
146 | fP2=p[2]; | |
147 | fP3=p[3]; | |
148 | fP4=p[4]/x; | |
149 | ||
9b280d80 | 150 | //Conversion of the covariance matrix |
67c3dcbe | 151 | Double_t cv[15]; |
152 | if (c) t.GetConstrainedExternalCovariance(cv); | |
153 | else t.GetExternalCovariance(cv); | |
154 | fC00=cv[0 ]; | |
155 | fC10=cv[1 ]; fC11=cv[2 ]; | |
156 | fC20=cv[3 ]; fC21=cv[4 ]; fC22=cv[5 ]; | |
157 | fC30=cv[6 ]; fC31=cv[7 ]; fC32=cv[8 ]; fC33=cv[9 ]; | |
158 | fC40=cv[10]/x; fC41=cv[11]/x; fC42=cv[12]/x; fC43=cv[13]/x; fC44=cv[14]/x/x; | |
006b5f7f | 159 | |
83d73500 | 160 | if (t.GetStatus()&AliESDtrack::kTIME) { |
161 | StartTimeIntegral(); | |
162 | Double_t times[10]; t.GetIntegratedTimes(times); SetIntegratedTimes(times); | |
163 | SetIntegratedLength(t.GetIntegratedLength()); | |
164 | } | |
165 | fESDtrack=&t; | |
babd135a | 166 | fNUsed = 0; |
167 | fReconstructed = kFALSE; | |
e43c066c | 168 | fNSkipped =0; |
169 | fNDeadZone = 0; | |
170 | fDeadZoneProbability = 0; | |
171 | for(Int_t i=0; i<6; i++) {fClIndex[i]=-1; fNy[i]=0; fNz[i]=0; fNormQ[i]=0; fNormChi2[i]=1000;} | |
172 | for(Int_t i=0; i<12; i++) {fDy[i]=0; fDz[i]=0; fSigmaY[i]=0; fSigmaZ[i]=0;fChi2MIP[i]=0;} | |
173 | fD[0]=0; fD[1]=0; | |
174 | fExpQ=40; | |
175 | fConstrain = kFALSE; | |
176 | fdEdxMismatch=0; | |
177 | fChi22 =0; | |
178 | ||
0aa211b1 | 179 | //if (!Invariant()) throw "AliITStrackV2: conversion failed !\n"; |
e43c066c | 180 | |
006b5f7f | 181 | } |
182 | ||
83d73500 | 183 | void AliITStrackV2::UpdateESDtrack(ULong_t flags) { |
184 | fESDtrack->UpdateTrackParams(this,flags); | |
babd135a | 185 | if (flags == AliESDtrack::kITSin) fESDtrack->SetITSChi2MIP(fChi2MIP); |
83d73500 | 186 | } |
67c3dcbe | 187 | void AliITStrackV2::SetConstrainedESDtrack(Double_t chi2) { |
188 | fESDtrack->SetConstrainedTrackParams(this,chi2); | |
189 | } | |
83d73500 | 190 | |
006b5f7f | 191 | //____________________________________________________________________________ |
192 | AliITStrackV2::AliITStrackV2(const AliITStrackV2& t) : AliKalmanTrack(t) { | |
193 | //------------------------------------------------------------------ | |
194 | //Copy constructor | |
195 | //------------------------------------------------------------------ | |
196 | fX=t.fX; | |
197 | fAlpha=t.fAlpha; | |
198 | fdEdx=t.fdEdx; | |
199 | ||
200 | fP0=t.fP0; fP1=t.fP1; fP2=t.fP2; fP3=t.fP3; fP4=t.fP4; | |
201 | ||
202 | fC00=t.fC00; | |
203 | fC10=t.fC10; fC11=t.fC11; | |
204 | fC20=t.fC20; fC21=t.fC21; fC22=t.fC22; | |
205 | fC30=t.fC30; fC31=t.fC31; fC32=t.fC32; fC33=t.fC33; | |
206 | fC40=t.fC40; fC41=t.fC41; fC42=t.fC42; fC43=t.fC43; fC44=t.fC44; | |
207 | ||
208 | Int_t n=GetNumberOfClusters(); | |
23efe5f1 | 209 | for (Int_t i=0; i<n; i++) { |
e43c066c | 210 | fIndex[i]=t.fIndex[i]; |
211 | if (i<4) fdEdxSample[i]=t.fdEdxSample[i]; | |
23efe5f1 | 212 | } |
83d73500 | 213 | fESDtrack=t.fESDtrack; |
babd135a | 214 | fNUsed = t.fNUsed; |
215 | fReconstructed = t.fReconstructed; | |
216 | fNSkipped = t.fNSkipped; | |
e43c066c | 217 | fNDeadZone = t.fNDeadZone; |
218 | fDeadZoneProbability = t.fDeadZoneProbability; | |
219 | fLab = t.fLab; | |
220 | fFakeRatio = t.fFakeRatio; | |
221 | fdEdxMismatch = t.fdEdxMismatch; | |
222 | fChi22 = t.fChi22; | |
223 | ||
224 | ||
225 | fD[0]=t.fD[0]; fD[1]=t.fD[1]; | |
226 | fExpQ= t.fExpQ; | |
227 | for(Int_t i=0; i<6; i++) { | |
228 | fClIndex[i]= t.fClIndex[i]; fNy[i]=t.fNy[i]; fNz[i]=t.fNz[i]; fNormQ[i]=t.fNormQ[i]; fNormChi2[i] = t.fNormChi2[i]; | |
229 | } | |
230 | for(Int_t i=0; i<12; i++) {fDy[i]=t.fDy[i]; fDz[i]=t.fDz[i]; | |
231 | fSigmaY[i]=t.fSigmaY[i]; fSigmaZ[i]=t.fSigmaZ[i];fChi2MIP[i]=t.fChi2MIP[i];} | |
232 | fConstrain = t.fConstrain; | |
233 | //memcpy(fDy,t.fDy,6*sizeof(Float_t)); | |
234 | //memcpy(fDz,t.fDz,6*sizeof(Float_t)); | |
235 | //memcpy(fSigmaY,t.fSigmaY,6*sizeof(Float_t)); | |
236 | //memcpy(fSigmaZ,t.fSigmaZ,6*sizeof(Float_t)); | |
237 | //memcpy(fChi2MIP,t.fChi2MIP,12*sizeof(Float_t)); | |
006b5f7f | 238 | } |
a9a2d814 | 239 | |
006b5f7f | 240 | //_____________________________________________________________________________ |
241 | Int_t AliITStrackV2::Compare(const TObject *o) const { | |
242 | //----------------------------------------------------------------- | |
243 | // This function compares tracks according to the their curvature | |
244 | //----------------------------------------------------------------- | |
7f6ddf58 | 245 | AliITStrackV2 *t=(AliITStrackV2*)o; |
a9a2d814 | 246 | //Double_t co=TMath::Abs(t->Get1Pt()); |
247 | //Double_t c =TMath::Abs(Get1Pt()); | |
e43c066c | 248 | Double_t co=t->GetSigmaY2()*t->GetSigmaZ2()*(0.5+TMath::Sqrt(0.5*t->fD[0]*t->fD[0]+t->fD[1]*t->fD[1])); |
249 | Double_t c =GetSigmaY2()*GetSigmaZ2()*(0.5+TMath::Sqrt(0.5*fD[0]*fD[0]+fD[1]*fD[1])); | |
006b5f7f | 250 | if (c>co) return 1; |
251 | else if (c<co) return -1; | |
252 | return 0; | |
253 | } | |
254 | ||
255 | //_____________________________________________________________________________ | |
256 | void AliITStrackV2::GetExternalCovariance(Double_t cc[15]) const { | |
257 | //------------------------------------------------------------------------- | |
258 | // This function returns an external representation of the covriance matrix. | |
259 | // (See comments in AliTPCtrack.h about external track representation) | |
260 | //------------------------------------------------------------------------- | |
9b280d80 | 261 | Double_t a=GetConvConst(); |
006b5f7f | 262 | |
263 | cc[0 ]=fC00; | |
264 | cc[1 ]=fC10; cc[2 ]=fC11; | |
265 | cc[3 ]=fC20; cc[4 ]=fC21; cc[5 ]=fC22; | |
266 | cc[6 ]=fC30; cc[7 ]=fC31; cc[8 ]=fC32; cc[9 ]=fC33; | |
267 | cc[10]=fC40*a; cc[11]=fC41*a; cc[12]=fC42*a; cc[13]=fC43*a; cc[14]=fC44*a*a; | |
268 | } | |
269 | ||
270 | //____________________________________________________________________________ | |
a9a2d814 | 271 | Int_t AliITStrackV2::PropagateToVertex(Double_t d,Double_t x0) { |
006b5f7f | 272 | //------------------------------------------------------------------ |
273 | //This function propagates a track to the minimal distance from the origin | |
274 | //------------------------------------------------------------------ | |
5b316485 | 275 | //Double_t xv=fP2*(fX*fP2 - fP0*TMath::Sqrt(1.- fP2*fP2)); //linear approxim. |
276 | Double_t tgf=-(fP4*fX - fP2)/(fP4*fP0 + TMath::Sqrt(1 - fP2*fP2)); | |
277 | Double_t snf=tgf/TMath::Sqrt(1.+ tgf*tgf); | |
278 | Double_t xv=(snf - fP2)/fP4 + fX; | |
279 | return PropagateTo(xv,d,x0); | |
006b5f7f | 280 | } |
281 | ||
282 | //____________________________________________________________________________ | |
283 | Int_t AliITStrackV2:: | |
284 | GetGlobalXYZat(Double_t xk, Double_t &x, Double_t &y, Double_t &z) const { | |
285 | //------------------------------------------------------------------ | |
286 | //This function returns a track position in the global system | |
287 | //------------------------------------------------------------------ | |
288 | Double_t dx=xk-fX; | |
289 | Double_t f1=fP2, f2=f1 + fP4*dx; | |
a9a2d814 | 290 | if (TMath::Abs(f2) >= 0.9999) { |
7f6ddf58 | 291 | Int_t n=GetNumberOfClusters(); |
292 | if (n>kWARN) | |
8676d691 | 293 | Warning("GetGlobalXYZat","Propagation failed (%d) !\n",n); |
006b5f7f | 294 | return 0; |
295 | } | |
296 | ||
297 | Double_t r1=sqrt(1.- f1*f1), r2=sqrt(1.- f2*f2); | |
298 | ||
299 | Double_t yk = fP0 + dx*(f1+f2)/(r1+r2); | |
300 | Double_t zk = fP1 + dx*(f1+f2)/(f1*r2 + f2*r1)*fP3; | |
301 | ||
302 | Double_t cs=TMath::Cos(fAlpha), sn=TMath::Sin(fAlpha); | |
303 | x = xk*cs - yk*sn; | |
304 | y = xk*sn + yk*cs; | |
305 | z = zk; | |
306 | ||
307 | return 1; | |
308 | } | |
309 | ||
310 | //_____________________________________________________________________________ | |
311 | Double_t AliITStrackV2::GetPredictedChi2(const AliCluster *c) const | |
312 | { | |
313 | //----------------------------------------------------------------- | |
314 | // This function calculates a predicted chi2 increment. | |
315 | //----------------------------------------------------------------- | |
316 | Double_t r00=c->GetSigmaY2(), r01=0., r11=c->GetSigmaZ2(); | |
317 | r00+=fC00; r01+=fC10; r11+=fC11; | |
babd135a | 318 | // |
006b5f7f | 319 | Double_t det=r00*r11 - r01*r01; |
7f6ddf58 | 320 | if (TMath::Abs(det) < 1.e-30) { |
006b5f7f | 321 | Int_t n=GetNumberOfClusters(); |
7f6ddf58 | 322 | if (n>kWARN) |
8676d691 | 323 | Warning("GetPredictedChi2","Singular matrix (%d) !\n",n); |
006b5f7f | 324 | return 1e10; |
325 | } | |
326 | Double_t tmp=r00; r00=r11; r11=tmp; r01=-r01; | |
33329428 | 327 | |
006b5f7f | 328 | Double_t dy=c->GetY() - fP0, dz=c->GetZ() - fP1; |
33329428 | 329 | |
006b5f7f | 330 | return (dy*r00*dy + 2*r01*dy*dz + dz*r11*dz)/det; |
331 | } | |
332 | ||
e43c066c | 333 | Double_t AliITStrackV2::GetPredictedChi2MI(Double_t cy, Double_t cz, Double_t cerry, Double_t cerrz) const |
334 | { | |
335 | //----------------------------------------------------------------- | |
336 | // This function calculates a predicted chi2 increment. | |
337 | //----------------------------------------------------------------- | |
338 | Double_t r00=cerry*cerry, r01=0., r11=cerrz*cerrz; | |
339 | r00+=fC00; r01+=fC10; r11+=fC11; | |
340 | // | |
341 | Double_t det=r00*r11 - r01*r01; | |
342 | if (TMath::Abs(det) < 1.e-30) { | |
343 | Int_t n=GetNumberOfClusters(); | |
344 | if (n>kWARN) | |
345 | Warning("GetPredictedChi2","Singular matrix (%d) !\n",n); | |
346 | return 1e10; | |
347 | } | |
348 | Double_t tmp=r00; r00=r11; r11=tmp; r01=-r01; | |
349 | ||
350 | Double_t dy=cy - fP0, dz=cz - fP1; | |
351 | ||
352 | return (dy*r00*dy + 2*r01*dy*dz + dz*r11*dz)/det; | |
353 | } | |
354 | ||
006b5f7f | 355 | //____________________________________________________________________________ |
a9a2d814 | 356 | Int_t AliITStrackV2::CorrectForMaterial(Double_t d, Double_t x0) { |
357 | //------------------------------------------------------------------ | |
358 | //This function corrects the track parameters for crossed material | |
359 | //------------------------------------------------------------------ | |
e43c066c | 360 | // Double_t p2=(1.+ GetTgl()*GetTgl())/(Get1Pt()*Get1Pt()); |
361 | Double_t p2=(1.+ fP3*fP3)/(Get1Pt()*Get1Pt()); | |
362 | Double_t et = p2 + GetMass()*GetMass(); | |
363 | Double_t beta2=p2/et; | |
364 | et = sqrt(et); | |
a9a2d814 | 365 | d*=TMath::Sqrt((1.+ fP3*fP3)/(1.- fP2*fP2)); |
e43c066c | 366 | //d*=TMath::Sqrt(1.+ fP3*fP3 +fP2*fP2/(1.- fP2*fP2)); |
a9a2d814 | 367 | |
368 | //Multiple scattering****************** | |
369 | if (d!=0) { | |
33329428 | 370 | Double_t theta2=14.1*14.1/(beta2*p2*1e6)*TMath::Abs(d); |
371 | //Double_t theta2=1.0259e-6*14*14/28/(beta2*p2)*TMath::Abs(d)*9.36*2.33; | |
a9a2d814 | 372 | fC22 += theta2*(1.- fP2*fP2)*(1. + fP3*fP3); |
373 | fC33 += theta2*(1. + fP3*fP3)*(1. + fP3*fP3); | |
374 | fC43 += theta2*fP3*fP4*(1. + fP3*fP3); | |
375 | fC44 += theta2*fP3*fP4*fP3*fP4; | |
376 | } | |
377 | ||
378 | //Energy losses************************ | |
379 | if (x0!=0.) { | |
380 | d*=x0; | |
e43c066c | 381 | // Double_t dE=0.153e-3/beta2*(log(5940*beta2/(1-beta2)) - beta2)*d; |
382 | //Double_t dE=0; | |
383 | Double_t dE = 0.265*0.153e-3*(39.2-55.6*beta2+28.7*beta2*beta2+27.41/beta2)*d; | |
384 | /* | |
385 | if (beta2/(1-beta2)>3.5*3.5){ | |
83d73500 | 386 | dE=0.153e-3/beta2*(log(3.5*5940)+0.5*log(beta2/(1-beta2)) - beta2)*d; |
e43c066c | 387 | } |
388 | else{ | |
389 | dE=0.153e-3/beta2*(log(5940*beta2/(1-beta2)) - beta2)*d; | |
390 | dE+=0.06e-3/(beta2*beta2)*d; | |
391 | } | |
392 | */ | |
393 | fP4*=(1.- et/p2*dE); | |
394 | Double_t delta44 = (dE*fP4*et/p2); | |
395 | delta44*=delta44; | |
396 | fC44+= delta44/400.; | |
a9a2d814 | 397 | } |
398 | ||
399 | if (!Invariant()) return 0; | |
400 | ||
401 | return 1; | |
402 | } | |
403 | ||
404 | //____________________________________________________________________________ | |
405 | Int_t AliITStrackV2::PropagateTo(Double_t xk, Double_t d, Double_t x0) { | |
006b5f7f | 406 | //------------------------------------------------------------------ |
407 | //This function propagates a track | |
408 | //------------------------------------------------------------------ | |
409 | Double_t x1=fX, x2=xk, dx=x2-x1; | |
410 | Double_t f1=fP2, f2=f1 + fP4*dx; | |
a9a2d814 | 411 | if (TMath::Abs(f2) >= 0.9999) { |
006b5f7f | 412 | Int_t n=GetNumberOfClusters(); |
7f6ddf58 | 413 | if (n>kWARN) |
8676d691 | 414 | Warning("PropagateTo","Propagation failed !\n",n); |
006b5f7f | 415 | return 0; |
416 | } | |
417 | ||
f29dbb4b | 418 | // old position [SR, GSI, 17.02.2003] |
419 | Double_t oldX = fX, oldY = fP0, oldZ = fP1; | |
420 | ||
006b5f7f | 421 | Double_t r1=sqrt(1.- f1*f1), r2=sqrt(1.- f2*f2); |
422 | ||
423 | fP0 += dx*(f1+f2)/(r1+r2); | |
424 | fP1 += dx*(f1+f2)/(f1*r2 + f2*r1)*fP3; | |
425 | fP2 += dx*fP4; | |
426 | ||
427 | //f = F - 1 | |
428 | ||
429 | Double_t f02= dx/(r1*r1*r1); | |
430 | Double_t f04=0.5*dx*dx/(r1*r1*r1); | |
431 | Double_t f12= dx*fP3*f1/(r1*r1*r1); | |
432 | Double_t f14=0.5*dx*dx*fP3*f1/(r1*r1*r1); | |
433 | Double_t f13= dx/r1; | |
434 | Double_t f24= dx; | |
435 | ||
436 | //b = C*ft | |
437 | Double_t b00=f02*fC20 + f04*fC40, b01=f12*fC20 + f14*fC40 + f13*fC30; | |
438 | Double_t b02=f24*fC40; | |
439 | Double_t b10=f02*fC21 + f04*fC41, b11=f12*fC21 + f14*fC41 + f13*fC31; | |
440 | Double_t b12=f24*fC41; | |
441 | Double_t b20=f02*fC22 + f04*fC42, b21=f12*fC22 + f14*fC42 + f13*fC32; | |
442 | Double_t b22=f24*fC42; | |
443 | Double_t b40=f02*fC42 + f04*fC44, b41=f12*fC42 + f14*fC44 + f13*fC43; | |
444 | Double_t b42=f24*fC44; | |
445 | Double_t b30=f02*fC32 + f04*fC43, b31=f12*fC32 + f14*fC43 + f13*fC33; | |
446 | Double_t b32=f24*fC43; | |
447 | ||
448 | //a = f*b = f*C*ft | |
449 | Double_t a00=f02*b20+f04*b40,a01=f02*b21+f04*b41,a02=f02*b22+f04*b42; | |
450 | Double_t a11=f12*b21+f14*b41+f13*b31,a12=f12*b22+f14*b42+f13*b32; | |
451 | Double_t a22=f24*b42; | |
452 | ||
453 | //F*C*Ft = C + (b + bt + a) | |
454 | fC00 += b00 + b00 + a00; | |
455 | fC10 += b10 + b01 + a01; | |
456 | fC20 += b20 + b02 + a02; | |
457 | fC30 += b30; | |
458 | fC40 += b40; | |
459 | fC11 += b11 + b11 + a11; | |
460 | fC21 += b21 + b12 + a12; | |
461 | fC31 += b31; | |
462 | fC41 += b41; | |
463 | fC22 += b22 + b22 + a22; | |
464 | fC32 += b32; | |
465 | fC42 += b42; | |
466 | ||
467 | fX=x2; | |
468 | ||
a9a2d814 | 469 | if (!CorrectForMaterial(d,x0)) return 0; |
006b5f7f | 470 | |
f29dbb4b | 471 | // Integrated Time [SR, GSI, 17.02.2003] |
880f41b9 | 472 | if (IsStartedTimeIntegral() && fX>oldX) { |
8676d691 | 473 | Double_t l2 = (fX-oldX)*(fX-oldX)+(fP0-oldY)*(fP0-oldY)+ |
474 | (fP1-oldZ)*(fP1-oldZ); | |
f29dbb4b | 475 | AddTimeStep(TMath::Sqrt(l2)); |
476 | } | |
477 | // | |
478 | ||
006b5f7f | 479 | return 1; |
480 | } | |
481 | ||
482 | //____________________________________________________________________________ | |
483 | Int_t AliITStrackV2::Update(const AliCluster* c, Double_t chi2, UInt_t index) { | |
484 | //------------------------------------------------------------------ | |
485 | //This function updates track parameters | |
486 | //------------------------------------------------------------------ | |
487 | Double_t p0=fP0,p1=fP1,p2=fP2,p3=fP3,p4=fP4; | |
488 | Double_t c00=fC00; | |
489 | Double_t c10=fC10, c11=fC11; | |
490 | Double_t c20=fC20, c21=fC21, c22=fC22; | |
491 | Double_t c30=fC30, c31=fC31, c32=fC32, c33=fC33; | |
492 | Double_t c40=fC40, c41=fC41, c42=fC42, c43=fC43, c44=fC44; | |
493 | ||
494 | ||
495 | Double_t r00=c->GetSigmaY2(), r01=0., r11=c->GetSigmaZ2(); | |
496 | r00+=fC00; r01+=fC10; r11+=fC11; | |
497 | Double_t det=r00*r11 - r01*r01; | |
498 | Double_t tmp=r00; r00=r11/det; r11=tmp/det; r01=-r01/det; | |
499 | ||
babd135a | 500 | |
006b5f7f | 501 | Double_t k00=fC00*r00+fC10*r01, k01=fC00*r01+fC10*r11; |
502 | Double_t k10=fC10*r00+fC11*r01, k11=fC10*r01+fC11*r11; | |
503 | Double_t k20=fC20*r00+fC21*r01, k21=fC20*r01+fC21*r11; | |
504 | Double_t k30=fC30*r00+fC31*r01, k31=fC30*r01+fC31*r11; | |
505 | Double_t k40=fC40*r00+fC41*r01, k41=fC40*r01+fC41*r11; | |
506 | ||
507 | Double_t dy=c->GetY() - fP0, dz=c->GetZ() - fP1; | |
babd135a | 508 | Int_t layer = (index & 0xf0000000) >> 28; |
509 | fDy[layer] = dy; | |
510 | fDz[layer] = dz; | |
511 | fSigmaY[layer] = TMath::Sqrt(c->GetSigmaY2()+fC00); | |
512 | fSigmaZ[layer] = TMath::Sqrt(c->GetSigmaZ2()+fC11); | |
513 | ||
006b5f7f | 514 | Double_t sf=fP2 + k20*dy + k21*dz; |
7f6ddf58 | 515 | |
006b5f7f | 516 | fP0 += k00*dy + k01*dz; |
517 | fP1 += k10*dy + k11*dz; | |
518 | fP2 = sf; | |
519 | fP3 += k30*dy + k31*dz; | |
520 | fP4 += k40*dy + k41*dz; | |
521 | ||
522 | Double_t c01=fC10, c02=fC20, c03=fC30, c04=fC40; | |
523 | Double_t c12=fC21, c13=fC31, c14=fC41; | |
524 | ||
525 | fC00-=k00*fC00+k01*fC10; fC10-=k00*c01+k01*fC11; | |
526 | fC20-=k00*c02+k01*c12; fC30-=k00*c03+k01*c13; | |
527 | fC40-=k00*c04+k01*c14; | |
528 | ||
529 | fC11-=k10*c01+k11*fC11; | |
530 | fC21-=k10*c02+k11*c12; fC31-=k10*c03+k11*c13; | |
531 | fC41-=k10*c04+k11*c14; | |
532 | ||
533 | fC22-=k20*c02+k21*c12; fC32-=k20*c03+k21*c13; | |
534 | fC42-=k20*c04+k21*c14; | |
535 | ||
536 | fC33-=k30*c03+k31*c13; | |
537 | fC43-=k30*c04+k31*c14; | |
538 | ||
539 | fC44-=k40*c04+k41*c14; | |
540 | ||
541 | if (!Invariant()) { | |
542 | fP0=p0; fP1=p1; fP2=p2; fP3=p3; fP4=p4; | |
543 | fC00=c00; | |
544 | fC10=c10; fC11=c11; | |
545 | fC20=c20; fC21=c21; fC22=c22; | |
546 | fC30=c30; fC31=c31; fC32=c32; fC33=c33; | |
547 | fC40=c40; fC41=c41; fC42=c42; fC43=c43; fC44=c44; | |
548 | return 0; | |
549 | } | |
550 | ||
67c3dcbe | 551 | if (chi2<0) return 1; |
552 | ||
006b5f7f | 553 | Int_t n=GetNumberOfClusters(); |
554 | fIndex[n]=index; | |
555 | SetNumberOfClusters(n+1); | |
556 | SetChi2(GetChi2()+chi2); | |
557 | ||
558 | return 1; | |
559 | } | |
560 | ||
e43c066c | 561 | //____________________________________________________________________________ |
562 | Int_t AliITStrackV2::UpdateMI(Double_t cy, Double_t cz, Double_t cerry, Double_t cerrz, Double_t chi2,UInt_t index) { | |
563 | //------------------------------------------------------------------ | |
564 | //This function updates track parameters | |
565 | //------------------------------------------------------------------ | |
566 | Double_t p0=fP0,p1=fP1,p2=fP2,p3=fP3,p4=fP4; | |
567 | Double_t c00=fC00; | |
568 | Double_t c10=fC10, c11=fC11; | |
569 | Double_t c20=fC20, c21=fC21, c22=fC22; | |
570 | Double_t c30=fC30, c31=fC31, c32=fC32, c33=fC33; | |
571 | Double_t c40=fC40, c41=fC41, c42=fC42, c43=fC43, c44=fC44; | |
572 | ||
573 | ||
574 | Double_t r00=cerry*cerry, r01=0., r11=cerrz*cerrz; | |
575 | r00+=fC00; r01+=fC10; r11+=fC11; | |
576 | Double_t det=r00*r11 - r01*r01; | |
577 | Double_t tmp=r00; r00=r11/det; r11=tmp/det; r01=-r01/det; | |
578 | ||
579 | ||
580 | Double_t k00=fC00*r00+fC10*r01, k01=fC00*r01+fC10*r11; | |
581 | Double_t k10=fC10*r00+fC11*r01, k11=fC10*r01+fC11*r11; | |
582 | Double_t k20=fC20*r00+fC21*r01, k21=fC20*r01+fC21*r11; | |
583 | Double_t k30=fC30*r00+fC31*r01, k31=fC30*r01+fC31*r11; | |
584 | Double_t k40=fC40*r00+fC41*r01, k41=fC40*r01+fC41*r11; | |
585 | ||
586 | Double_t dy=cy - fP0, dz=cz - fP1; | |
587 | Int_t layer = (index & 0xf0000000) >> 28; | |
588 | fDy[layer] = dy; | |
589 | fDz[layer] = dz; | |
590 | fSigmaY[layer] = TMath::Sqrt(cerry*cerry+fC00); | |
591 | fSigmaZ[layer] = TMath::Sqrt(cerrz*cerrz+fC11); | |
592 | ||
593 | Double_t sf=fP2 + k20*dy + k21*dz; | |
594 | ||
595 | fP0 += k00*dy + k01*dz; | |
596 | fP1 += k10*dy + k11*dz; | |
597 | fP2 = sf; | |
598 | fP3 += k30*dy + k31*dz; | |
599 | fP4 += k40*dy + k41*dz; | |
600 | ||
601 | Double_t c01=fC10, c02=fC20, c03=fC30, c04=fC40; | |
602 | Double_t c12=fC21, c13=fC31, c14=fC41; | |
603 | ||
604 | fC00-=k00*fC00+k01*fC10; fC10-=k00*c01+k01*fC11; | |
605 | fC20-=k00*c02+k01*c12; fC30-=k00*c03+k01*c13; | |
606 | fC40-=k00*c04+k01*c14; | |
607 | ||
608 | fC11-=k10*c01+k11*fC11; | |
609 | fC21-=k10*c02+k11*c12; fC31-=k10*c03+k11*c13; | |
610 | fC41-=k10*c04+k11*c14; | |
611 | ||
612 | fC22-=k20*c02+k21*c12; fC32-=k20*c03+k21*c13; | |
613 | fC42-=k20*c04+k21*c14; | |
614 | ||
615 | fC33-=k30*c03+k31*c13; | |
616 | fC43-=k30*c04+k31*c14; | |
617 | ||
618 | fC44-=k40*c04+k41*c14; | |
619 | ||
620 | if (!Invariant()) { | |
621 | fP0=p0; fP1=p1; fP2=p2; fP3=p3; fP4=p4; | |
622 | fC00=c00; | |
623 | fC10=c10; fC11=c11; | |
624 | fC20=c20; fC21=c21; fC22=c22; | |
625 | fC30=c30; fC31=c31; fC32=c32; fC33=c33; | |
626 | fC40=c40; fC41=c41; fC42=c42; fC43=c43; fC44=c44; | |
627 | return 0; | |
628 | } | |
629 | ||
630 | if (chi2<0) return 1; | |
631 | Int_t n=GetNumberOfClusters(); | |
632 | fIndex[n]=index; | |
633 | SetNumberOfClusters(n+1); | |
634 | SetChi2(GetChi2()+chi2); | |
635 | ||
636 | return 1; | |
637 | } | |
638 | ||
006b5f7f | 639 | Int_t AliITStrackV2::Invariant() const { |
640 | //------------------------------------------------------------------ | |
641 | // This function is for debugging purpose only | |
642 | //------------------------------------------------------------------ | |
7f6ddf58 | 643 | Int_t n=GetNumberOfClusters(); |
644 | ||
a9a2d814 | 645 | if (TMath::Abs(fP2)>=0.9999){ |
8676d691 | 646 | if (n>kWARN) Warning("Invariant","fP2=%f\n",fP2); |
a9a2d814 | 647 | return 0; |
648 | } | |
649 | if (fC00<=0 || fC00>9.) { | |
8676d691 | 650 | if (n>kWARN) Warning("Invariant","fC00=%f\n",fC00); |
a9a2d814 | 651 | return 0; |
652 | } | |
653 | if (fC11<=0 || fC11>9.) { | |
8676d691 | 654 | if (n>kWARN) Warning("Invariant","fC11=%f\n",fC11); |
a9a2d814 | 655 | return 0; |
656 | } | |
657 | if (fC22<=0 || fC22>1.) { | |
8676d691 | 658 | if (n>kWARN) Warning("Invariant","fC22=%f\n",fC22); |
a9a2d814 | 659 | return 0; |
660 | } | |
661 | if (fC33<=0 || fC33>1.) { | |
8676d691 | 662 | if (n>kWARN) Warning("Invariant","fC33=%f\n",fC33); |
a9a2d814 | 663 | return 0; |
664 | } | |
665 | if (fC44<=0 || fC44>6e-5) { | |
8676d691 | 666 | if (n>kWARN) Warning("Invariant","fC44=%f\n",fC44); |
a9a2d814 | 667 | return 0; |
14825d5a | 668 | } |
14825d5a | 669 | return 1; |
006b5f7f | 670 | } |
671 | ||
672 | //____________________________________________________________________________ | |
a9a2d814 | 673 | Int_t AliITStrackV2::Propagate(Double_t alp,Double_t xk) { |
006b5f7f | 674 | //------------------------------------------------------------------ |
675 | //This function propagates a track | |
676 | //------------------------------------------------------------------ | |
33329428 | 677 | Double_t alpha=fAlpha, x=fX; |
006b5f7f | 678 | Double_t p0=fP0,p1=fP1,p2=fP2,p3=fP3,p4=fP4; |
679 | Double_t c00=fC00; | |
680 | Double_t c10=fC10, c11=fC11; | |
681 | Double_t c20=fC20, c21=fC21, c22=fC22; | |
682 | Double_t c30=fC30, c31=fC31, c32=fC32, c33=fC33; | |
683 | Double_t c40=fC40, c41=fC41, c42=fC42, c43=fC43, c44=fC44; | |
684 | ||
33329428 | 685 | if (alp < -TMath::Pi()) alp += 2*TMath::Pi(); |
686 | else if (alp >= TMath::Pi()) alp -= 2*TMath::Pi(); | |
687 | Double_t ca=TMath::Cos(alp-fAlpha), sa=TMath::Sin(alp-fAlpha); | |
688 | Double_t sf=fP2, cf=TMath::Sqrt(1.- fP2*fP2); | |
006b5f7f | 689 | |
e43c066c | 690 | TMatrixD *T=0; |
33329428 | 691 | // **** rotation ********************** |
692 | { | |
006b5f7f | 693 | fAlpha = alp; |
33329428 | 694 | fX = x*ca + p0*sa; |
695 | fP0= -x*sa + p0*ca; | |
696 | fP2= sf*ca - cf*sa; | |
697 | ||
e43c066c | 698 | static TMatrixD C(5,5); |
699 | C(0,0)=c00; | |
700 | C(1,0)=c10; C(1,1)=c11; | |
701 | C(2,0)=c20; C(2,1)=c21; C(2,2)=c22; | |
702 | C(3,0)=c30; C(3,1)=c31; C(3,2)=c32; C(3,3)=c33; | |
703 | C(4,0)=c40; C(4,1)=c41; C(4,2)=c42; C(4,3)=c43; C(4,4)=c44; | |
704 | C(0,1)=C(1,0); | |
705 | C(0,2)=C(2,0); C(1,2)=C(2,1); | |
706 | C(0,3)=C(3,0); C(1,3)=C(3,1); C(2,3)=C(3,2); | |
707 | C(0,4)=C(4,0); C(1,4)=C(4,1); C(2,4)=C(4,2); C(3,4)=C(4,3); | |
708 | ||
709 | ||
710 | static TMatrixD F(6,5); | |
711 | F(0,0)=sa; | |
712 | F(1,0)=ca; | |
713 | F(2,1)=F(4,3)=F(5,4)=1; | |
714 | F(3,2)=ca + sf/cf*sa; | |
715 | ||
716 | //TMatrixD tmp(C,TMatrixD::kMult,TMatrixD(TMatrixD::kTransposed, F)); | |
717 | ||
718 | static TMatrixD Ft(5,6); | |
719 | Ft(0,0)=sa; | |
720 | Ft(0,1)=ca; | |
721 | Ft(1,2)=Ft(3,4)=Ft(4,5)=1; | |
722 | Ft(2,3)=ca + sf/cf*sa; | |
723 | ||
724 | TMatrixD tmp(C,TMatrixD::kMult,Ft); | |
725 | T=new TMatrixD(F,TMatrixD::kMult,tmp); | |
726 | ||
727 | ||
33329428 | 728 | } |
006b5f7f | 729 | |
33329428 | 730 | // **** translation ****************** |
731 | { | |
732 | Double_t dx=xk-fX; | |
006b5f7f | 733 | Double_t f1=fP2, f2=f1 + fP4*dx; |
a9a2d814 | 734 | if (TMath::Abs(f2) >= 0.9999) { |
006b5f7f | 735 | Int_t n=GetNumberOfClusters(); |
7f6ddf58 | 736 | if (n>kWARN) |
8676d691 | 737 | Warning("Propagate","Propagation failed (%d) !\n",n); |
006b5f7f | 738 | return 0; |
739 | } | |
33329428 | 740 | Double_t r1=TMath::Sqrt(1.- f1*f1), r2=TMath::Sqrt(1.- f2*f2); |
006b5f7f | 741 | |
33329428 | 742 | fX=xk; |
006b5f7f | 743 | fP0 += dx*(f1+f2)/(r1+r2); |
744 | fP1 += dx*(f1+f2)/(f1*r2 + f2*r1)*fP3; | |
745 | fP2 += dx*fP4; | |
746 | ||
e43c066c | 747 | static TMatrixD F(5,6); |
748 | F(0,1)=F(1,2)=F(2,3)=F(3,4)=F(4,5)=1; | |
749 | F(0,3)=dx/(r1+r2)*(2+(f1+f2)*(f2/r2+f1/r1)/(r1+r2)); | |
750 | F(0,5)=dx*dx/(r1+r2)*(1+(f1+f2)*f2/(r1+r2)); | |
751 | F(1,3)=dx*fP3/(f1*r2 + f2*r1)*(2-(f1+f2)*(r2-f1*f2/r2+r1-f2*f1/r1)/(f1*r2 + f2*r1)); | |
752 | F(1,4)=dx*(f1+f2)/(f1*r2 + f2*r1); | |
753 | F(1,5)=dx*dx*fP3/(f1*r2 + f2*r1)*(1-(f1+f2)*(-f1*f2/r2+r1)/(f1*r2 + f2*r1)); | |
754 | F(2,5)=dx; | |
755 | F(0,0)=-1/(r1+r2)*((f1+f2)+dx*fP4*(1+(f1+f2)/(r1+r2)*f2/r2)); | |
756 | F(1,0)=-fP3/(f1*r2 + f2*r1)*((f1+f2)+dx*fP4*(1+(f1+f2)/(f1*r2 + f2*r1)*(f1*f2/r2-r1))); | |
757 | F(2,0)=-fP4; | |
758 | ||
759 | TMatrixD tmp(*T,TMatrixD::kMult,TMatrixD(TMatrixD::kTransposed, F)); | |
760 | delete T; | |
761 | TMatrixD C(F,TMatrixD::kMult,tmp); | |
762 | ||
763 | fC00=C(0,0); | |
764 | fC10=C(1,0); fC11=C(1,1); | |
765 | fC20=C(2,0); fC21=C(2,1); fC22=C(2,2); | |
766 | fC30=C(3,0); fC31=C(3,1); fC32=C(3,2); fC33=C(3,3); | |
767 | fC40=C(4,0); fC41=C(4,1); fC42=C(4,2); fC43=C(4,3); fC44=C(4,4); | |
006b5f7f | 768 | |
006b5f7f | 769 | if (!Invariant()) { |
33329428 | 770 | fAlpha=alpha; |
771 | fX=x; | |
006b5f7f | 772 | fP0=p0; fP1=p1; fP2=p2; fP3=p3; fP4=p4; |
773 | fC00=c00; | |
774 | fC10=c10; fC11=c11; | |
775 | fC20=c20; fC21=c21; fC22=c22; | |
776 | fC30=c30; fC31=c31; fC32=c32; fC33=c33; | |
777 | fC40=c40; fC41=c41; fC42=c42; fC43=c43; fC44=c44; | |
778 | return 0; | |
779 | } | |
33329428 | 780 | } |
006b5f7f | 781 | |
782 | return 1; | |
783 | } | |
784 | ||
e43c066c | 785 | |
786 | ||
787 | Int_t AliITStrackV2::GetProlongationFast(Double_t alp, Double_t xk,Double_t &y, Double_t &z) | |
788 | { | |
789 | //----------------------------------------------------------------------------- | |
790 | //get fast prolongation | |
791 | //----------------------------------------------------------------------------- | |
792 | Double_t ca=TMath::Cos(alp-fAlpha), sa=TMath::Sin(alp-fAlpha); | |
793 | Double_t cf=TMath::Sqrt(1.- fP2*fP2); | |
794 | // **** rotation ********************** | |
795 | y= -fX*sa + fP0*ca; | |
796 | // **** translation ****************** | |
797 | Double_t dx = xk- fX*ca - fP0*sa; | |
798 | Double_t f1=fP2*ca - cf*sa, f2=f1 + fP4*dx; | |
799 | if (TMath::Abs(f2) >= 0.9999) { | |
800 | return 0; | |
801 | } | |
802 | Double_t r1=TMath::Sqrt(1.- f1*f1), r2=TMath::Sqrt(1.- f2*f2); | |
803 | y += dx*(f1+f2)/(r1+r2); | |
804 | z = fP1+dx*(f1+f2)/(f1*r2 + f2*r1)*fP3; | |
805 | return 1; | |
806 | } | |
807 | ||
808 | ||
a6a6f799 | 809 | Double_t AliITStrackV2::GetD(Double_t x, Double_t y) const { |
006b5f7f | 810 | //------------------------------------------------------------------ |
a6a6f799 | 811 | // This function calculates the transverse impact parameter |
812 | // with respect to a point with global coordinates (x,y) | |
006b5f7f | 813 | //------------------------------------------------------------------ |
a6a6f799 | 814 | Double_t xt=fX, yt=fP0; |
815 | ||
816 | Double_t sn=TMath::Sin(fAlpha), cs=TMath::Cos(fAlpha); | |
817 | Double_t a = x*cs + y*sn; | |
818 | y = -x*sn + y*cs; x=a; | |
819 | xt-=x; yt-=y; | |
820 | ||
821 | sn=fP4*xt - fP2; cs=fP4*yt + TMath::Sqrt(1.- fP2*fP2); | |
822 | a=2*(xt*fP2 - yt*TMath::Sqrt(1.- fP2*fP2))-fP4*(xt*xt + yt*yt); | |
006b5f7f | 823 | if (fP4<0) a=-a; |
824 | return a/(1 + TMath::Sqrt(sn*sn + cs*cs)); | |
a9a2d814 | 825 | } |
006b5f7f | 826 | |
babd135a | 827 | Double_t AliITStrackV2::GetZat(Double_t x) const { |
828 | //------------------------------------------------------------------ | |
829 | // This function calculates the z at given x point - in current coordinate system | |
830 | //------------------------------------------------------------------ | |
831 | Double_t x1=fX, x2=x, dx=x2-x1; | |
832 | // | |
833 | Double_t f1=fP2, f2=f1 + fP4*dx; | |
834 | if (TMath::Abs(f2) >= 0.9999) { | |
835 | return 10000000; | |
836 | } | |
babd135a | 837 | Double_t r1=sqrt(1.- f1*f1), r2=sqrt(1.- f2*f2); |
838 | Double_t z = fP1 + dx*(f1+f2)/(f1*r2 + f2*r1)*fP3; | |
839 | return z; | |
840 | } | |
841 | ||
842 | ||
843 | ||
844 | ||
8676d691 | 845 | Int_t AliITStrackV2::Improve(Double_t x0,Double_t xyz[3],Double_t ers[3]) { |
a9a2d814 | 846 | //------------------------------------------------------------------ |
847 | //This function improves angular track parameters | |
848 | //------------------------------------------------------------------ | |
8676d691 | 849 | Double_t cs=TMath::Cos(fAlpha), sn=TMath::Sin(fAlpha); |
850 | //Double_t xv = xyz[0]*cs + xyz[1]*sn; // vertex | |
851 | Double_t yv =-xyz[0]*sn + xyz[1]*cs; // in the | |
852 | Double_t zv = xyz[2]; // local frame | |
a9a2d814 | 853 | Double_t dy=fP0-yv, dz=fP1-zv; |
854 | Double_t r2=fX*fX+dy*dy; | |
855 | Double_t p2=(1.+ GetTgl()*GetTgl())/(Get1Pt()*Get1Pt()); | |
856 | Double_t beta2=p2/(p2 + GetMass()*GetMass()); | |
857 | x0*=TMath::Sqrt((1.+ GetTgl()*GetTgl())/(1.- GetSnp()*GetSnp())); | |
8676d691 | 858 | Double_t theta2=14.1*14.1/(beta2*p2*1e6)*x0; |
859 | //Double_t theta2=1.0259e-6*14*14/28/(beta2*p2)*x0*9.36*2.33; | |
a9a2d814 | 860 | { |
861 | Double_t parp=0.5*(fP4*fX + dy*TMath::Sqrt(4/r2-fP4*fP4)); | |
862 | Double_t sigma2p = theta2*(1.- GetSnp()*GetSnp())*(1. + GetTgl()*GetTgl()); | |
863 | sigma2p += fC00/r2*(1.- dy*dy/r2)*(1.- dy*dy/r2); | |
8676d691 | 864 | sigma2p += ers[1]*ers[1]/r2; |
a9a2d814 | 865 | sigma2p += 0.25*fC44*fX*fX; |
866 | Double_t eps2p=sigma2p/(fC22+sigma2p); | |
867 | fP0 += fC20/(fC22+sigma2p)*(parp-fP2); | |
868 | fP2 = eps2p*fP2 + (1-eps2p)*parp; | |
869 | fC22 *= eps2p; | |
870 | fC20 *= eps2p; | |
871 | } | |
872 | { | |
873 | Double_t parl=0.5*fP4*dz/TMath::ASin(0.5*fP4*TMath::Sqrt(r2)); | |
874 | Double_t sigma2l=theta2; | |
875 | sigma2l += fC11/r2+fC00*dy*dy*dz*dz/(r2*r2*r2); | |
8676d691 | 876 | sigma2l += ers[2]*ers[2]/r2; |
a9a2d814 | 877 | Double_t eps2l=sigma2l/(fC33+sigma2l); |
878 | fP1 += fC31/(fC33+sigma2l)*(parl-fP3); | |
879 | fP4 += fC43/(fC33+sigma2l)*(parl-fP3); | |
880 | fP3 = eps2l*fP3 + (1-eps2l)*parl; | |
881 | fC33 *= eps2l; fC43 *= eps2l; | |
882 | fC31 *= eps2l; | |
883 | } | |
884 | if (!Invariant()) return 0; | |
885 | return 1; | |
886 | } | |
006b5f7f | 887 | |
a9a2d814 | 888 | /* |
006b5f7f | 889 | Int_t AliITStrackV2::Improve(Double_t x0,Double_t yv,Double_t zv) { |
890 | //------------------------------------------------------------------ | |
891 | //This function improves angular track parameters | |
892 | //------------------------------------------------------------------ | |
893 | Double_t dy=fP0-yv, dz=fP1-zv; | |
894 | Double_t r2=fX*fX+dy*dy; | |
895 | Double_t p2=(1.+ GetTgl()*GetTgl())/(Get1Pt()*Get1Pt()); | |
7f6ddf58 | 896 | Double_t beta2=p2/(p2 + GetMass()*GetMass()); |
006b5f7f | 897 | x0*=TMath::Sqrt((1.+ GetTgl()*GetTgl())/(1.- GetSnp()*GetSnp())); |
a9a2d814 | 898 | //Double_t theta2=14.1*14.1/(beta2*p2*1e6)*x0; |
899 | Double_t theta2=1.0259e-6*14*14/28/(beta2*p2)*x0*9.36*2.33; | |
006b5f7f | 900 | |
901 | Double_t par=0.5*(fP4*fX + dy*TMath::Sqrt(4/r2-fP4*fP4)); | |
902 | Double_t sigma2 = theta2*(1.- GetSnp()*GetSnp())*(1. + GetTgl()*GetTgl()); | |
903 | sigma2 += fC00/r2*(1.- dy*dy/r2)*(1.- dy*dy/r2); | |
904 | sigma2 += kSigmaYV*kSigmaYV/r2; | |
905 | sigma2 += 0.25*fC44*fX*fX; | |
906 | Double_t eps2=sigma2/(fC22+sigma2), eps=TMath::Sqrt(eps2); | |
907 | if (10*r2*fC44<fC22) { | |
908 | fP2 = eps2*fP2 + (1-eps2)*par; | |
909 | fC22*=eps2; fC21*=eps; fC20*=eps; fC32*=eps; fC42*=eps; | |
910 | } | |
911 | ||
912 | par=0.5*fP4*dz/TMath::ASin(0.5*fP4*TMath::Sqrt(r2)); | |
913 | sigma2=theta2; | |
914 | sigma2 += fC11/r2+fC00*dy*dy*dz*dz/(r2*r2*r2); | |
915 | sigma2 += kSigmaZV*kSigmaZV/r2; | |
916 | eps2=sigma2/(fC33+sigma2); eps=TMath::Sqrt(eps2); | |
917 | Double_t tgl=fP3; | |
918 | fP3 = eps2*fP3 + (1-eps2)*par; | |
919 | fC33*=eps2; fC32*=eps; fC31*=eps; fC30*=eps; fC43*=eps; | |
920 | ||
921 | eps=TMath::Sqrt((1+fP3*fP3)/(1+tgl*tgl)); | |
922 | fP4*=eps; | |
923 | fC44*=eps*eps; fC43*=eps;fC42*=eps; fC41*=eps; fC40*=eps; | |
924 | ||
925 | if (!Invariant()) return 0; | |
926 | return 1; | |
927 | } | |
006b5f7f | 928 | */ |
14825d5a | 929 | void AliITStrackV2::ResetCovariance() { |
930 | //------------------------------------------------------------------ | |
931 | //This function makes a track forget its history :) | |
932 | //------------------------------------------------------------------ | |
933 | ||
934 | fC00*=10.; | |
935 | fC10=0.; fC11*=10.; | |
936 | fC20=0.; fC21=0.; fC22*=10.; | |
937 | fC30=0.; fC31=0.; fC32=0.; fC33*=10.; | |
938 | fC40=0.; fC41=0.; fC42=0.; fC43=0.; fC44*=10.; | |
939 | ||
940 | } | |
23efe5f1 | 941 | |
942 | void AliITStrackV2::CookdEdx(Double_t low, Double_t up) { | |
943 | //----------------------------------------------------------------- | |
a9a2d814 | 944 | // This function calculates dE/dX within the "low" and "up" cuts. |
945 | // Origin: Boris Batyunya, JINR, Boris.Batiounia@cern.ch | |
23efe5f1 | 946 | //----------------------------------------------------------------- |
23efe5f1 | 947 | // The clusters order is: SSD-2, SSD-1, SDD-2, SDD-1, SPD-2, SPD-1 |
c0dd5278 | 948 | |
949 | Int_t i; | |
950 | Int_t nc=0; | |
951 | for (i=0; i<GetNumberOfClusters(); i++) { | |
952 | Int_t idx=GetClusterIndex(i); | |
953 | idx=(idx&0xf0000000)>>28; | |
954 | if (idx>1) nc++; // Take only SSD and SDD | |
955 | } | |
23efe5f1 | 956 | |
a9a2d814 | 957 | Int_t swap;//stupid sorting |
23efe5f1 | 958 | do { |
959 | swap=0; | |
960 | for (i=0; i<nc-1; i++) { | |
961 | if (fdEdxSample[i]<=fdEdxSample[i+1]) continue; | |
962 | Float_t tmp=fdEdxSample[i]; | |
963 | fdEdxSample[i]=fdEdxSample[i+1]; fdEdxSample[i+1]=tmp; | |
964 | swap++; | |
965 | } | |
966 | } while (swap); | |
967 | ||
a9a2d814 | 968 | Int_t nl=Int_t(low*nc), nu=Int_t(up*nc); //b.b. to take two lowest dEdX |
969 | // values from four ones choose | |
970 | // nu=2 | |
23efe5f1 | 971 | Float_t dedx=0; |
a9a2d814 | 972 | for (i=nl; i<nu; i++) dedx += fdEdxSample[i]; |
c0dd5278 | 973 | if (nu-nl>0) dedx /= (nu-nl); |
23efe5f1 | 974 | |
23efe5f1 | 975 | SetdEdx(dedx); |
976 | } |