]>
Commit | Line | Data |
---|---|---|
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" | |
517b130f | 28 | #include "AliTPCtrack.h" |
83d73500 | 29 | #include "AliESDtrack.h" |
006b5f7f | 30 | #include "AliITStrackV2.h" |
31 | ||
32 | ClassImp(AliITStrackV2) | |
33 | ||
7f6ddf58 | 34 | const Int_t kWARN=5; |
8676d691 | 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), | |
63 | fReconstructed(kFALSE), | |
83d73500 | 64 | fESDtrack(0) |
e6ba4672 | 65 | { |
22b13da0 | 66 | for(Int_t i=0; i<kMaxLayer; i++) fIndex[i]=0; |
67 | for(Int_t i=0; i<4; i++) fdEdxSample[i]=0; | |
babd135a | 68 | for(Int_t i=0; i<6; i++) {fDy[i]=0; fDz[i]=0; fSigmaY[i]=0; fSigmaZ[i]=0; fChi2MIP[i]=0;} |
22b13da0 | 69 | } |
83d73500 | 70 | |
006b5f7f | 71 | //____________________________________________________________________________ |
e1a65e92 | 72 | AliITStrackV2::AliITStrackV2(const AliTPCtrack& t) throw (const Char_t *) : |
73 | AliKalmanTrack(t) { | |
006b5f7f | 74 | //------------------------------------------------------------------ |
9b280d80 | 75 | //Conversion TPC track -> ITS track |
006b5f7f | 76 | //------------------------------------------------------------------ |
006b5f7f | 77 | SetChi2(0.); |
78 | SetNumberOfClusters(0); | |
14825d5a | 79 | |
7f6ddf58 | 80 | fdEdx = t.GetdEdx(); |
81 | SetMass(t.GetMass()); | |
82 | ||
006b5f7f | 83 | fAlpha = t.GetAlpha(); |
84 | if (fAlpha < -TMath::Pi()) fAlpha += 2*TMath::Pi(); | |
85 | else if (fAlpha >= TMath::Pi()) fAlpha -= 2*TMath::Pi(); | |
86 | ||
83d73500 | 87 | //Conversion of the track parameters |
88 | Double_t x,p[5]; t.GetExternalParameters(x,p); | |
89 | fX=x; x=GetConvConst(); | |
90 | fP0=p[0]; | |
91 | fP1=p[1]; | |
92 | fP2=p[2]; | |
93 | fP3=p[3]; | |
94 | fP4=p[4]/x; | |
95 | ||
96 | //Conversion of the covariance matrix | |
97 | Double_t c[15]; t.GetExternalCovariance(c); | |
98 | ||
99 | fC00=c[0 ]; | |
100 | fC10=c[1 ]; fC11=c[2 ]; | |
101 | fC20=c[3 ]; fC21=c[4 ]; fC22=c[5 ]; | |
102 | fC30=c[6 ]; fC31=c[7 ]; fC32=c[8 ]; fC33=c[9 ]; | |
103 | fC40=c[10]/x; fC41=c[11]/x; fC42=c[12]/x; fC43=c[13]/x; fC44=c[14]/x/x; | |
104 | ||
babd135a | 105 | for(Int_t i=0; i<6; i++) {fDy[i]=0; fDz[i]=0; fSigmaY[i]=0; fSigmaZ[i]=0;} |
106 | // | |
83d73500 | 107 | if (!Invariant()) throw "AliITStrackV2: conversion failed !\n"; |
108 | ||
109 | } | |
110 | ||
111 | //____________________________________________________________________________ | |
67c3dcbe | 112 | AliITStrackV2::AliITStrackV2(AliESDtrack& t,Bool_t c) throw (const Char_t *) : |
83d73500 | 113 | AliKalmanTrack() { |
114 | //------------------------------------------------------------------ | |
67c3dcbe | 115 | // Conversion ESD track -> ITS track. |
116 | // If c==kTRUE, create the ITS track out of the constrained params. | |
83d73500 | 117 | //------------------------------------------------------------------ |
118 | SetNumberOfClusters(t.GetITSclusters(fIndex)); | |
119 | SetLabel(t.GetLabel()); | |
120 | SetMass(t.GetMass()); | |
121 | ||
122 | fdEdx=t.GetITSsignal(); | |
123 | fAlpha = t.GetAlpha(); | |
124 | if (fAlpha < -TMath::Pi()) fAlpha += 2*TMath::Pi(); | |
125 | else if (fAlpha >= TMath::Pi()) fAlpha -= 2*TMath::Pi(); | |
126 | ||
9b280d80 | 127 | //Conversion of the track parameters |
67c3dcbe | 128 | Double_t x,p[5]; |
129 | if (c) t.GetConstrainedExternalParameters(x,p); | |
130 | else t.GetExternalParameters(x,p); | |
9b280d80 | 131 | fX=x; x=GetConvConst(); |
006b5f7f | 132 | fP0=p[0]; |
133 | fP1=p[1]; | |
134 | fP2=p[2]; | |
135 | fP3=p[3]; | |
136 | fP4=p[4]/x; | |
137 | ||
9b280d80 | 138 | //Conversion of the covariance matrix |
67c3dcbe | 139 | Double_t cv[15]; |
140 | if (c) t.GetConstrainedExternalCovariance(cv); | |
141 | else t.GetExternalCovariance(cv); | |
142 | fC00=cv[0 ]; | |
143 | fC10=cv[1 ]; fC11=cv[2 ]; | |
144 | fC20=cv[3 ]; fC21=cv[4 ]; fC22=cv[5 ]; | |
145 | fC30=cv[6 ]; fC31=cv[7 ]; fC32=cv[8 ]; fC33=cv[9 ]; | |
146 | fC40=cv[10]/x; fC41=cv[11]/x; fC42=cv[12]/x; fC43=cv[13]/x; fC44=cv[14]/x/x; | |
006b5f7f | 147 | |
83d73500 | 148 | if (t.GetStatus()&AliESDtrack::kTIME) { |
149 | StartTimeIntegral(); | |
150 | Double_t times[10]; t.GetIntegratedTimes(times); SetIntegratedTimes(times); | |
151 | SetIntegratedLength(t.GetIntegratedLength()); | |
152 | } | |
153 | fESDtrack=&t; | |
babd135a | 154 | fNUsed = 0; |
155 | fReconstructed = kFALSE; | |
156 | fNSkipped =0; | |
157 | for(Int_t i=0; i<6; i++) {fDy[i]=0; fDz[i]=0; fSigmaY[i]=0; fSigmaZ[i]=0;; fChi2MIP[i]=0;} | |
0aa211b1 | 158 | //if (!Invariant()) throw "AliITStrackV2: conversion failed !\n"; |
babd135a | 159 | SetFakeRatio(t.GetITSFakeRatio()); |
006b5f7f | 160 | } |
161 | ||
83d73500 | 162 | void AliITStrackV2::UpdateESDtrack(ULong_t flags) { |
163 | fESDtrack->UpdateTrackParams(this,flags); | |
babd135a | 164 | if (flags == AliESDtrack::kITSin) fESDtrack->SetITSChi2MIP(fChi2MIP); |
83d73500 | 165 | } |
67c3dcbe | 166 | void AliITStrackV2::SetConstrainedESDtrack(Double_t chi2) { |
167 | fESDtrack->SetConstrainedTrackParams(this,chi2); | |
168 | } | |
83d73500 | 169 | |
006b5f7f | 170 | //____________________________________________________________________________ |
171 | AliITStrackV2::AliITStrackV2(const AliITStrackV2& t) : AliKalmanTrack(t) { | |
172 | //------------------------------------------------------------------ | |
173 | //Copy constructor | |
174 | //------------------------------------------------------------------ | |
175 | fX=t.fX; | |
176 | fAlpha=t.fAlpha; | |
177 | fdEdx=t.fdEdx; | |
178 | ||
179 | fP0=t.fP0; fP1=t.fP1; fP2=t.fP2; fP3=t.fP3; fP4=t.fP4; | |
180 | ||
181 | fC00=t.fC00; | |
182 | fC10=t.fC10; fC11=t.fC11; | |
183 | fC20=t.fC20; fC21=t.fC21; fC22=t.fC22; | |
184 | fC30=t.fC30; fC31=t.fC31; fC32=t.fC32; fC33=t.fC33; | |
185 | fC40=t.fC40; fC41=t.fC41; fC42=t.fC42; fC43=t.fC43; fC44=t.fC44; | |
186 | ||
187 | Int_t n=GetNumberOfClusters(); | |
23efe5f1 | 188 | for (Int_t i=0; i<n; i++) { |
a9a2d814 | 189 | fIndex[i]=t.fIndex[i]; |
190 | if (i<4) fdEdxSample[i]=t.fdEdxSample[i]; | |
23efe5f1 | 191 | } |
83d73500 | 192 | fESDtrack=t.fESDtrack; |
babd135a | 193 | fNUsed = t.fNUsed; |
194 | fReconstructed = t.fReconstructed; | |
195 | fNSkipped = t.fNSkipped; | |
196 | for(Int_t i=0; i<6; i++) {fDy[i]=t.fDy[i]; fDz[i]=t.fDz[i]; fSigmaY[i]=t.fSigmaY[i]; fSigmaZ[i]=t.fSigmaZ[i];; fChi2MIP[i]=t.fChi2MIP[i];} | |
006b5f7f | 197 | } |
a9a2d814 | 198 | |
006b5f7f | 199 | //_____________________________________________________________________________ |
200 | Int_t AliITStrackV2::Compare(const TObject *o) const { | |
201 | //----------------------------------------------------------------- | |
202 | // This function compares tracks according to the their curvature | |
203 | //----------------------------------------------------------------- | |
7f6ddf58 | 204 | AliITStrackV2 *t=(AliITStrackV2*)o; |
a9a2d814 | 205 | //Double_t co=TMath::Abs(t->Get1Pt()); |
206 | //Double_t c =TMath::Abs(Get1Pt()); | |
babd135a | 207 | Double_t co=t->GetSigmaY2()*t->GetSigmaZ2()*TMath::Sqrt(TMath::Abs(fP4)); |
208 | Double_t c =GetSigmaY2()*GetSigmaZ2()*TMath::Sqrt(TMath::Abs(fP4)); | |
006b5f7f | 209 | if (c>co) return 1; |
210 | else if (c<co) return -1; | |
211 | return 0; | |
212 | } | |
213 | ||
214 | //_____________________________________________________________________________ | |
215 | void AliITStrackV2::GetExternalCovariance(Double_t cc[15]) const { | |
216 | //------------------------------------------------------------------------- | |
217 | // This function returns an external representation of the covriance matrix. | |
218 | // (See comments in AliTPCtrack.h about external track representation) | |
219 | //------------------------------------------------------------------------- | |
9b280d80 | 220 | Double_t a=GetConvConst(); |
006b5f7f | 221 | |
222 | cc[0 ]=fC00; | |
223 | cc[1 ]=fC10; cc[2 ]=fC11; | |
224 | cc[3 ]=fC20; cc[4 ]=fC21; cc[5 ]=fC22; | |
225 | cc[6 ]=fC30; cc[7 ]=fC31; cc[8 ]=fC32; cc[9 ]=fC33; | |
226 | cc[10]=fC40*a; cc[11]=fC41*a; cc[12]=fC42*a; cc[13]=fC43*a; cc[14]=fC44*a*a; | |
227 | } | |
228 | ||
229 | //____________________________________________________________________________ | |
a9a2d814 | 230 | Int_t AliITStrackV2::PropagateToVertex(Double_t d,Double_t x0) { |
006b5f7f | 231 | //------------------------------------------------------------------ |
232 | //This function propagates a track to the minimal distance from the origin | |
233 | //------------------------------------------------------------------ | |
5b316485 | 234 | //Double_t xv=fP2*(fX*fP2 - fP0*TMath::Sqrt(1.- fP2*fP2)); //linear approxim. |
235 | Double_t tgf=-(fP4*fX - fP2)/(fP4*fP0 + TMath::Sqrt(1 - fP2*fP2)); | |
236 | Double_t snf=tgf/TMath::Sqrt(1.+ tgf*tgf); | |
237 | Double_t xv=(snf - fP2)/fP4 + fX; | |
238 | return PropagateTo(xv,d,x0); | |
006b5f7f | 239 | } |
240 | ||
241 | //____________________________________________________________________________ | |
242 | Int_t AliITStrackV2:: | |
243 | GetGlobalXYZat(Double_t xk, Double_t &x, Double_t &y, Double_t &z) const { | |
244 | //------------------------------------------------------------------ | |
245 | //This function returns a track position in the global system | |
246 | //------------------------------------------------------------------ | |
247 | Double_t dx=xk-fX; | |
248 | Double_t f1=fP2, f2=f1 + fP4*dx; | |
a9a2d814 | 249 | if (TMath::Abs(f2) >= 0.9999) { |
7f6ddf58 | 250 | Int_t n=GetNumberOfClusters(); |
251 | if (n>kWARN) | |
8676d691 | 252 | Warning("GetGlobalXYZat","Propagation failed (%d) !\n",n); |
006b5f7f | 253 | return 0; |
254 | } | |
255 | ||
256 | Double_t r1=sqrt(1.- f1*f1), r2=sqrt(1.- f2*f2); | |
257 | ||
258 | Double_t yk = fP0 + dx*(f1+f2)/(r1+r2); | |
259 | Double_t zk = fP1 + dx*(f1+f2)/(f1*r2 + f2*r1)*fP3; | |
260 | ||
261 | Double_t cs=TMath::Cos(fAlpha), sn=TMath::Sin(fAlpha); | |
262 | x = xk*cs - yk*sn; | |
263 | y = xk*sn + yk*cs; | |
264 | z = zk; | |
265 | ||
266 | return 1; | |
267 | } | |
268 | ||
269 | //_____________________________________________________________________________ | |
270 | Double_t AliITStrackV2::GetPredictedChi2(const AliCluster *c) const | |
271 | { | |
272 | //----------------------------------------------------------------- | |
273 | // This function calculates a predicted chi2 increment. | |
274 | //----------------------------------------------------------------- | |
275 | Double_t r00=c->GetSigmaY2(), r01=0., r11=c->GetSigmaZ2(); | |
276 | r00+=fC00; r01+=fC10; r11+=fC11; | |
babd135a | 277 | // |
006b5f7f | 278 | Double_t det=r00*r11 - r01*r01; |
7f6ddf58 | 279 | if (TMath::Abs(det) < 1.e-30) { |
006b5f7f | 280 | Int_t n=GetNumberOfClusters(); |
7f6ddf58 | 281 | if (n>kWARN) |
8676d691 | 282 | Warning("GetPredictedChi2","Singular matrix (%d) !\n",n); |
006b5f7f | 283 | return 1e10; |
284 | } | |
285 | Double_t tmp=r00; r00=r11; r11=tmp; r01=-r01; | |
33329428 | 286 | |
006b5f7f | 287 | Double_t dy=c->GetY() - fP0, dz=c->GetZ() - fP1; |
33329428 | 288 | |
006b5f7f | 289 | return (dy*r00*dy + 2*r01*dy*dz + dz*r11*dz)/det; |
290 | } | |
291 | ||
006b5f7f | 292 | //____________________________________________________________________________ |
a9a2d814 | 293 | Int_t AliITStrackV2::CorrectForMaterial(Double_t d, Double_t x0) { |
294 | //------------------------------------------------------------------ | |
295 | //This function corrects the track parameters for crossed material | |
296 | //------------------------------------------------------------------ | |
297 | Double_t p2=(1.+ GetTgl()*GetTgl())/(Get1Pt()*Get1Pt()); | |
298 | Double_t beta2=p2/(p2 + GetMass()*GetMass()); | |
299 | d*=TMath::Sqrt((1.+ fP3*fP3)/(1.- fP2*fP2)); | |
300 | ||
301 | //Multiple scattering****************** | |
302 | if (d!=0) { | |
33329428 | 303 | Double_t theta2=14.1*14.1/(beta2*p2*1e6)*TMath::Abs(d); |
304 | //Double_t theta2=1.0259e-6*14*14/28/(beta2*p2)*TMath::Abs(d)*9.36*2.33; | |
a9a2d814 | 305 | fC22 += theta2*(1.- fP2*fP2)*(1. + fP3*fP3); |
306 | fC33 += theta2*(1. + fP3*fP3)*(1. + fP3*fP3); | |
307 | fC43 += theta2*fP3*fP4*(1. + fP3*fP3); | |
308 | fC44 += theta2*fP3*fP4*fP3*fP4; | |
309 | } | |
310 | ||
311 | //Energy losses************************ | |
312 | if (x0!=0.) { | |
313 | d*=x0; | |
314 | Double_t dE=0.153e-3/beta2*(log(5940*beta2/(1-beta2)) - beta2)*d; | |
83d73500 | 315 | if (beta2/(1-beta2)>3.5*3.5) |
316 | dE=0.153e-3/beta2*(log(3.5*5940)+0.5*log(beta2/(1-beta2)) - beta2)*d; | |
a9a2d814 | 317 | fP4*=(1.- sqrt(p2+GetMass()*GetMass())/p2*dE); |
318 | } | |
319 | ||
320 | if (!Invariant()) return 0; | |
321 | ||
322 | return 1; | |
323 | } | |
324 | ||
325 | //____________________________________________________________________________ | |
326 | Int_t AliITStrackV2::PropagateTo(Double_t xk, Double_t d, Double_t x0) { | |
006b5f7f | 327 | //------------------------------------------------------------------ |
328 | //This function propagates a track | |
329 | //------------------------------------------------------------------ | |
330 | Double_t x1=fX, x2=xk, dx=x2-x1; | |
331 | Double_t f1=fP2, f2=f1 + fP4*dx; | |
a9a2d814 | 332 | if (TMath::Abs(f2) >= 0.9999) { |
006b5f7f | 333 | Int_t n=GetNumberOfClusters(); |
7f6ddf58 | 334 | if (n>kWARN) |
8676d691 | 335 | Warning("PropagateTo","Propagation failed !\n",n); |
006b5f7f | 336 | return 0; |
337 | } | |
338 | ||
f29dbb4b | 339 | // old position [SR, GSI, 17.02.2003] |
340 | Double_t oldX = fX, oldY = fP0, oldZ = fP1; | |
341 | ||
006b5f7f | 342 | Double_t r1=sqrt(1.- f1*f1), r2=sqrt(1.- f2*f2); |
343 | ||
344 | fP0 += dx*(f1+f2)/(r1+r2); | |
345 | fP1 += dx*(f1+f2)/(f1*r2 + f2*r1)*fP3; | |
346 | fP2 += dx*fP4; | |
347 | ||
348 | //f = F - 1 | |
349 | ||
350 | Double_t f02= dx/(r1*r1*r1); | |
351 | Double_t f04=0.5*dx*dx/(r1*r1*r1); | |
352 | Double_t f12= dx*fP3*f1/(r1*r1*r1); | |
353 | Double_t f14=0.5*dx*dx*fP3*f1/(r1*r1*r1); | |
354 | Double_t f13= dx/r1; | |
355 | Double_t f24= dx; | |
356 | ||
357 | //b = C*ft | |
358 | Double_t b00=f02*fC20 + f04*fC40, b01=f12*fC20 + f14*fC40 + f13*fC30; | |
359 | Double_t b02=f24*fC40; | |
360 | Double_t b10=f02*fC21 + f04*fC41, b11=f12*fC21 + f14*fC41 + f13*fC31; | |
361 | Double_t b12=f24*fC41; | |
362 | Double_t b20=f02*fC22 + f04*fC42, b21=f12*fC22 + f14*fC42 + f13*fC32; | |
363 | Double_t b22=f24*fC42; | |
364 | Double_t b40=f02*fC42 + f04*fC44, b41=f12*fC42 + f14*fC44 + f13*fC43; | |
365 | Double_t b42=f24*fC44; | |
366 | Double_t b30=f02*fC32 + f04*fC43, b31=f12*fC32 + f14*fC43 + f13*fC33; | |
367 | Double_t b32=f24*fC43; | |
368 | ||
369 | //a = f*b = f*C*ft | |
370 | Double_t a00=f02*b20+f04*b40,a01=f02*b21+f04*b41,a02=f02*b22+f04*b42; | |
371 | Double_t a11=f12*b21+f14*b41+f13*b31,a12=f12*b22+f14*b42+f13*b32; | |
372 | Double_t a22=f24*b42; | |
373 | ||
374 | //F*C*Ft = C + (b + bt + a) | |
375 | fC00 += b00 + b00 + a00; | |
376 | fC10 += b10 + b01 + a01; | |
377 | fC20 += b20 + b02 + a02; | |
378 | fC30 += b30; | |
379 | fC40 += b40; | |
380 | fC11 += b11 + b11 + a11; | |
381 | fC21 += b21 + b12 + a12; | |
382 | fC31 += b31; | |
383 | fC41 += b41; | |
384 | fC22 += b22 + b22 + a22; | |
385 | fC32 += b32; | |
386 | fC42 += b42; | |
387 | ||
388 | fX=x2; | |
389 | ||
a9a2d814 | 390 | if (!CorrectForMaterial(d,x0)) return 0; |
006b5f7f | 391 | |
f29dbb4b | 392 | // Integrated Time [SR, GSI, 17.02.2003] |
880f41b9 | 393 | if (IsStartedTimeIntegral() && fX>oldX) { |
8676d691 | 394 | Double_t l2 = (fX-oldX)*(fX-oldX)+(fP0-oldY)*(fP0-oldY)+ |
395 | (fP1-oldZ)*(fP1-oldZ); | |
f29dbb4b | 396 | AddTimeStep(TMath::Sqrt(l2)); |
397 | } | |
398 | // | |
399 | ||
006b5f7f | 400 | return 1; |
401 | } | |
402 | ||
403 | //____________________________________________________________________________ | |
404 | Int_t AliITStrackV2::Update(const AliCluster* c, Double_t chi2, UInt_t index) { | |
405 | //------------------------------------------------------------------ | |
406 | //This function updates track parameters | |
407 | //------------------------------------------------------------------ | |
408 | Double_t p0=fP0,p1=fP1,p2=fP2,p3=fP3,p4=fP4; | |
409 | Double_t c00=fC00; | |
410 | Double_t c10=fC10, c11=fC11; | |
411 | Double_t c20=fC20, c21=fC21, c22=fC22; | |
412 | Double_t c30=fC30, c31=fC31, c32=fC32, c33=fC33; | |
413 | Double_t c40=fC40, c41=fC41, c42=fC42, c43=fC43, c44=fC44; | |
414 | ||
415 | ||
416 | Double_t r00=c->GetSigmaY2(), r01=0., r11=c->GetSigmaZ2(); | |
417 | r00+=fC00; r01+=fC10; r11+=fC11; | |
418 | Double_t det=r00*r11 - r01*r01; | |
419 | Double_t tmp=r00; r00=r11/det; r11=tmp/det; r01=-r01/det; | |
420 | ||
babd135a | 421 | |
006b5f7f | 422 | Double_t k00=fC00*r00+fC10*r01, k01=fC00*r01+fC10*r11; |
423 | Double_t k10=fC10*r00+fC11*r01, k11=fC10*r01+fC11*r11; | |
424 | Double_t k20=fC20*r00+fC21*r01, k21=fC20*r01+fC21*r11; | |
425 | Double_t k30=fC30*r00+fC31*r01, k31=fC30*r01+fC31*r11; | |
426 | Double_t k40=fC40*r00+fC41*r01, k41=fC40*r01+fC41*r11; | |
427 | ||
428 | Double_t dy=c->GetY() - fP0, dz=c->GetZ() - fP1; | |
babd135a | 429 | Int_t layer = (index & 0xf0000000) >> 28; |
430 | fDy[layer] = dy; | |
431 | fDz[layer] = dz; | |
432 | fSigmaY[layer] = TMath::Sqrt(c->GetSigmaY2()+fC00); | |
433 | fSigmaZ[layer] = TMath::Sqrt(c->GetSigmaZ2()+fC11); | |
434 | ||
006b5f7f | 435 | Double_t sf=fP2 + k20*dy + k21*dz; |
7f6ddf58 | 436 | |
006b5f7f | 437 | fP0 += k00*dy + k01*dz; |
438 | fP1 += k10*dy + k11*dz; | |
439 | fP2 = sf; | |
440 | fP3 += k30*dy + k31*dz; | |
441 | fP4 += k40*dy + k41*dz; | |
442 | ||
443 | Double_t c01=fC10, c02=fC20, c03=fC30, c04=fC40; | |
444 | Double_t c12=fC21, c13=fC31, c14=fC41; | |
445 | ||
446 | fC00-=k00*fC00+k01*fC10; fC10-=k00*c01+k01*fC11; | |
447 | fC20-=k00*c02+k01*c12; fC30-=k00*c03+k01*c13; | |
448 | fC40-=k00*c04+k01*c14; | |
449 | ||
450 | fC11-=k10*c01+k11*fC11; | |
451 | fC21-=k10*c02+k11*c12; fC31-=k10*c03+k11*c13; | |
452 | fC41-=k10*c04+k11*c14; | |
453 | ||
454 | fC22-=k20*c02+k21*c12; fC32-=k20*c03+k21*c13; | |
455 | fC42-=k20*c04+k21*c14; | |
456 | ||
457 | fC33-=k30*c03+k31*c13; | |
458 | fC43-=k30*c04+k31*c14; | |
459 | ||
460 | fC44-=k40*c04+k41*c14; | |
461 | ||
462 | if (!Invariant()) { | |
463 | fP0=p0; fP1=p1; fP2=p2; fP3=p3; fP4=p4; | |
464 | fC00=c00; | |
465 | fC10=c10; fC11=c11; | |
466 | fC20=c20; fC21=c21; fC22=c22; | |
467 | fC30=c30; fC31=c31; fC32=c32; fC33=c33; | |
468 | fC40=c40; fC41=c41; fC42=c42; fC43=c43; fC44=c44; | |
469 | return 0; | |
470 | } | |
471 | ||
67c3dcbe | 472 | if (chi2<0) return 1; |
473 | ||
006b5f7f | 474 | Int_t n=GetNumberOfClusters(); |
475 | fIndex[n]=index; | |
476 | SetNumberOfClusters(n+1); | |
477 | SetChi2(GetChi2()+chi2); | |
478 | ||
479 | return 1; | |
480 | } | |
481 | ||
006b5f7f | 482 | Int_t AliITStrackV2::Invariant() const { |
483 | //------------------------------------------------------------------ | |
484 | // This function is for debugging purpose only | |
485 | //------------------------------------------------------------------ | |
7f6ddf58 | 486 | Int_t n=GetNumberOfClusters(); |
487 | ||
a9a2d814 | 488 | if (TMath::Abs(fP2)>=0.9999){ |
8676d691 | 489 | if (n>kWARN) Warning("Invariant","fP2=%f\n",fP2); |
a9a2d814 | 490 | return 0; |
491 | } | |
492 | if (fC00<=0 || fC00>9.) { | |
8676d691 | 493 | if (n>kWARN) Warning("Invariant","fC00=%f\n",fC00); |
a9a2d814 | 494 | return 0; |
495 | } | |
496 | if (fC11<=0 || fC11>9.) { | |
8676d691 | 497 | if (n>kWARN) Warning("Invariant","fC11=%f\n",fC11); |
a9a2d814 | 498 | return 0; |
499 | } | |
500 | if (fC22<=0 || fC22>1.) { | |
8676d691 | 501 | if (n>kWARN) Warning("Invariant","fC22=%f\n",fC22); |
a9a2d814 | 502 | return 0; |
503 | } | |
504 | if (fC33<=0 || fC33>1.) { | |
8676d691 | 505 | if (n>kWARN) Warning("Invariant","fC33=%f\n",fC33); |
a9a2d814 | 506 | return 0; |
507 | } | |
508 | if (fC44<=0 || fC44>6e-5) { | |
8676d691 | 509 | if (n>kWARN) Warning("Invariant","fC44=%f\n",fC44); |
a9a2d814 | 510 | return 0; |
14825d5a | 511 | } |
14825d5a | 512 | return 1; |
006b5f7f | 513 | } |
514 | ||
515 | //____________________________________________________________________________ | |
a9a2d814 | 516 | Int_t AliITStrackV2::Propagate(Double_t alp,Double_t xk) { |
006b5f7f | 517 | //------------------------------------------------------------------ |
518 | //This function propagates a track | |
519 | //------------------------------------------------------------------ | |
33329428 | 520 | Double_t alpha=fAlpha, x=fX; |
006b5f7f | 521 | Double_t p0=fP0,p1=fP1,p2=fP2,p3=fP3,p4=fP4; |
522 | Double_t c00=fC00; | |
523 | Double_t c10=fC10, c11=fC11; | |
524 | Double_t c20=fC20, c21=fC21, c22=fC22; | |
525 | Double_t c30=fC30, c31=fC31, c32=fC32, c33=fC33; | |
526 | Double_t c40=fC40, c41=fC41, c42=fC42, c43=fC43, c44=fC44; | |
527 | ||
33329428 | 528 | if (alp < -TMath::Pi()) alp += 2*TMath::Pi(); |
529 | else if (alp >= TMath::Pi()) alp -= 2*TMath::Pi(); | |
530 | Double_t ca=TMath::Cos(alp-fAlpha), sa=TMath::Sin(alp-fAlpha); | |
531 | Double_t sf=fP2, cf=TMath::Sqrt(1.- fP2*fP2); | |
006b5f7f | 532 | |
33329428 | 533 | TMatrixD *T=0; |
534 | // **** rotation ********************** | |
535 | { | |
006b5f7f | 536 | fAlpha = alp; |
33329428 | 537 | fX = x*ca + p0*sa; |
538 | fP0= -x*sa + p0*ca; | |
539 | fP2= sf*ca - cf*sa; | |
540 | ||
541 | TMatrixD C(5,5); | |
542 | C(0,0)=c00; | |
543 | C(1,0)=c10; C(1,1)=c11; | |
544 | C(2,0)=c20; C(2,1)=c21; C(2,2)=c22; | |
545 | C(3,0)=c30; C(3,1)=c31; C(3,2)=c32; C(3,3)=c33; | |
546 | C(4,0)=c40; C(4,1)=c41; C(4,2)=c42; C(4,3)=c43; C(4,4)=c44; | |
547 | C(0,1)=C(1,0); | |
548 | C(0,2)=C(2,0); C(1,2)=C(2,1); | |
549 | C(0,3)=C(3,0); C(1,3)=C(3,1); C(2,3)=C(3,2); | |
550 | C(0,4)=C(4,0); C(1,4)=C(4,1); C(2,4)=C(4,2); C(3,4)=C(4,3); | |
006b5f7f | 551 | |
33329428 | 552 | TMatrixD F(6,5); |
553 | F(0,0)=sa; | |
554 | F(1,0)=ca; | |
555 | F(2,1)=F(4,3)=F(5,4)=1; | |
556 | F(3,2)=ca + sf/cf*sa; | |
006b5f7f | 557 | |
33329428 | 558 | TMatrixD tmp(C,TMatrixD::kMult,TMatrixD(TMatrixD::kTransposed, F)); |
559 | T=new TMatrixD(F,TMatrixD::kMult,tmp); | |
560 | } | |
006b5f7f | 561 | |
33329428 | 562 | // **** translation ****************** |
563 | { | |
564 | Double_t dx=xk-fX; | |
006b5f7f | 565 | Double_t f1=fP2, f2=f1 + fP4*dx; |
a9a2d814 | 566 | if (TMath::Abs(f2) >= 0.9999) { |
006b5f7f | 567 | Int_t n=GetNumberOfClusters(); |
7f6ddf58 | 568 | if (n>kWARN) |
8676d691 | 569 | Warning("Propagate","Propagation failed (%d) !\n",n); |
006b5f7f | 570 | return 0; |
571 | } | |
33329428 | 572 | Double_t r1=TMath::Sqrt(1.- f1*f1), r2=TMath::Sqrt(1.- f2*f2); |
006b5f7f | 573 | |
33329428 | 574 | fX=xk; |
006b5f7f | 575 | fP0 += dx*(f1+f2)/(r1+r2); |
576 | fP1 += dx*(f1+f2)/(f1*r2 + f2*r1)*fP3; | |
577 | fP2 += dx*fP4; | |
578 | ||
33329428 | 579 | TMatrixD F(5,6); |
580 | F(0,1)=F(1,2)=F(2,3)=F(3,4)=F(4,5)=1; | |
581 | F(0,3)=dx/(r1+r2)*(2+(f1+f2)*(f2/r2+f1/r1)/(r1+r2)); | |
582 | F(0,5)=dx*dx/(r1+r2)*(1+(f1+f2)*f2/(r1+r2)); | |
583 | F(1,3)=dx*fP3/(f1*r2 + f2*r1)*(2-(f1+f2)*(r2-f1*f2/r2+r1-f2*f1/r1)/(f1*r2 + f2*r1)); | |
584 | F(1,4)=dx*(f1+f2)/(f1*r2 + f2*r1); | |
585 | F(1,5)=dx*dx*fP3/(f1*r2 + f2*r1)*(1-(f1+f2)*(-f1*f2/r2+r1)/(f1*r2 + f2*r1)); | |
586 | F(2,5)=dx; | |
587 | F(0,0)=-1/(r1+r2)*((f1+f2)+dx*fP4*(1+(f1+f2)/(r1+r2)*f2/r2)); | |
588 | F(1,0)=-fP3/(f1*r2 + f2*r1)*((f1+f2)+dx*fP4*(1+(f1+f2)/(f1*r2 + f2*r1)*(f1*f2/r2-r1))); | |
589 | F(2,0)=-fP4; | |
590 | ||
591 | TMatrixD tmp(*T,TMatrixD::kMult,TMatrixD(TMatrixD::kTransposed, F)); | |
592 | delete T; | |
593 | TMatrixD C(F,TMatrixD::kMult,tmp); | |
006b5f7f | 594 | |
595 | fC00=C(0,0); | |
596 | fC10=C(1,0); fC11=C(1,1); | |
597 | fC20=C(2,0); fC21=C(2,1); fC22=C(2,2); | |
598 | fC30=C(3,0); fC31=C(3,1); fC32=C(3,2); fC33=C(3,3); | |
599 | fC40=C(4,0); fC41=C(4,1); fC42=C(4,2); fC43=C(4,3); fC44=C(4,4); | |
600 | ||
006b5f7f | 601 | if (!Invariant()) { |
33329428 | 602 | fAlpha=alpha; |
603 | fX=x; | |
006b5f7f | 604 | fP0=p0; fP1=p1; fP2=p2; fP3=p3; fP4=p4; |
605 | fC00=c00; | |
606 | fC10=c10; fC11=c11; | |
607 | fC20=c20; fC21=c21; fC22=c22; | |
608 | fC30=c30; fC31=c31; fC32=c32; fC33=c33; | |
609 | fC40=c40; fC41=c41; fC42=c42; fC43=c43; fC44=c44; | |
610 | return 0; | |
611 | } | |
33329428 | 612 | } |
006b5f7f | 613 | |
614 | return 1; | |
615 | } | |
616 | ||
a6a6f799 | 617 | Double_t AliITStrackV2::GetD(Double_t x, Double_t y) const { |
006b5f7f | 618 | //------------------------------------------------------------------ |
a6a6f799 | 619 | // This function calculates the transverse impact parameter |
620 | // with respect to a point with global coordinates (x,y) | |
006b5f7f | 621 | //------------------------------------------------------------------ |
a6a6f799 | 622 | Double_t xt=fX, yt=fP0; |
623 | ||
624 | Double_t sn=TMath::Sin(fAlpha), cs=TMath::Cos(fAlpha); | |
625 | Double_t a = x*cs + y*sn; | |
626 | y = -x*sn + y*cs; x=a; | |
627 | xt-=x; yt-=y; | |
628 | ||
629 | sn=fP4*xt - fP2; cs=fP4*yt + TMath::Sqrt(1.- fP2*fP2); | |
630 | a=2*(xt*fP2 - yt*TMath::Sqrt(1.- fP2*fP2))-fP4*(xt*xt + yt*yt); | |
006b5f7f | 631 | if (fP4<0) a=-a; |
632 | return a/(1 + TMath::Sqrt(sn*sn + cs*cs)); | |
a9a2d814 | 633 | } |
006b5f7f | 634 | |
babd135a | 635 | Double_t AliITStrackV2::GetZat(Double_t x) const { |
636 | //------------------------------------------------------------------ | |
637 | // This function calculates the z at given x point - in current coordinate system | |
638 | //------------------------------------------------------------------ | |
639 | Double_t x1=fX, x2=x, dx=x2-x1; | |
640 | // | |
641 | Double_t f1=fP2, f2=f1 + fP4*dx; | |
642 | if (TMath::Abs(f2) >= 0.9999) { | |
643 | return 10000000; | |
644 | } | |
645 | ||
646 | Double_t r1=sqrt(1.- f1*f1), r2=sqrt(1.- f2*f2); | |
647 | Double_t z = fP1 + dx*(f1+f2)/(f1*r2 + f2*r1)*fP3; | |
648 | return z; | |
649 | } | |
650 | ||
651 | ||
652 | ||
653 | ||
8676d691 | 654 | Int_t AliITStrackV2::Improve(Double_t x0,Double_t xyz[3],Double_t ers[3]) { |
a9a2d814 | 655 | //------------------------------------------------------------------ |
656 | //This function improves angular track parameters | |
657 | //------------------------------------------------------------------ | |
8676d691 | 658 | Double_t cs=TMath::Cos(fAlpha), sn=TMath::Sin(fAlpha); |
659 | //Double_t xv = xyz[0]*cs + xyz[1]*sn; // vertex | |
660 | Double_t yv =-xyz[0]*sn + xyz[1]*cs; // in the | |
661 | Double_t zv = xyz[2]; // local frame | |
a9a2d814 | 662 | Double_t dy=fP0-yv, dz=fP1-zv; |
663 | Double_t r2=fX*fX+dy*dy; | |
664 | Double_t p2=(1.+ GetTgl()*GetTgl())/(Get1Pt()*Get1Pt()); | |
665 | Double_t beta2=p2/(p2 + GetMass()*GetMass()); | |
666 | x0*=TMath::Sqrt((1.+ GetTgl()*GetTgl())/(1.- GetSnp()*GetSnp())); | |
8676d691 | 667 | Double_t theta2=14.1*14.1/(beta2*p2*1e6)*x0; |
668 | //Double_t theta2=1.0259e-6*14*14/28/(beta2*p2)*x0*9.36*2.33; | |
a9a2d814 | 669 | { |
670 | Double_t parp=0.5*(fP4*fX + dy*TMath::Sqrt(4/r2-fP4*fP4)); | |
671 | Double_t sigma2p = theta2*(1.- GetSnp()*GetSnp())*(1. + GetTgl()*GetTgl()); | |
672 | sigma2p += fC00/r2*(1.- dy*dy/r2)*(1.- dy*dy/r2); | |
8676d691 | 673 | sigma2p += ers[1]*ers[1]/r2; |
a9a2d814 | 674 | sigma2p += 0.25*fC44*fX*fX; |
675 | Double_t eps2p=sigma2p/(fC22+sigma2p); | |
676 | fP0 += fC20/(fC22+sigma2p)*(parp-fP2); | |
677 | fP2 = eps2p*fP2 + (1-eps2p)*parp; | |
678 | fC22 *= eps2p; | |
679 | fC20 *= eps2p; | |
680 | } | |
681 | { | |
682 | Double_t parl=0.5*fP4*dz/TMath::ASin(0.5*fP4*TMath::Sqrt(r2)); | |
683 | Double_t sigma2l=theta2; | |
684 | sigma2l += fC11/r2+fC00*dy*dy*dz*dz/(r2*r2*r2); | |
8676d691 | 685 | sigma2l += ers[2]*ers[2]/r2; |
a9a2d814 | 686 | Double_t eps2l=sigma2l/(fC33+sigma2l); |
687 | fP1 += fC31/(fC33+sigma2l)*(parl-fP3); | |
688 | fP4 += fC43/(fC33+sigma2l)*(parl-fP3); | |
689 | fP3 = eps2l*fP3 + (1-eps2l)*parl; | |
690 | fC33 *= eps2l; fC43 *= eps2l; | |
691 | fC31 *= eps2l; | |
692 | } | |
693 | if (!Invariant()) return 0; | |
694 | return 1; | |
695 | } | |
006b5f7f | 696 | |
a9a2d814 | 697 | /* |
006b5f7f | 698 | Int_t AliITStrackV2::Improve(Double_t x0,Double_t yv,Double_t zv) { |
699 | //------------------------------------------------------------------ | |
700 | //This function improves angular track parameters | |
701 | //------------------------------------------------------------------ | |
702 | Double_t dy=fP0-yv, dz=fP1-zv; | |
703 | Double_t r2=fX*fX+dy*dy; | |
704 | Double_t p2=(1.+ GetTgl()*GetTgl())/(Get1Pt()*Get1Pt()); | |
7f6ddf58 | 705 | Double_t beta2=p2/(p2 + GetMass()*GetMass()); |
006b5f7f | 706 | x0*=TMath::Sqrt((1.+ GetTgl()*GetTgl())/(1.- GetSnp()*GetSnp())); |
a9a2d814 | 707 | //Double_t theta2=14.1*14.1/(beta2*p2*1e6)*x0; |
708 | Double_t theta2=1.0259e-6*14*14/28/(beta2*p2)*x0*9.36*2.33; | |
006b5f7f | 709 | |
710 | Double_t par=0.5*(fP4*fX + dy*TMath::Sqrt(4/r2-fP4*fP4)); | |
711 | Double_t sigma2 = theta2*(1.- GetSnp()*GetSnp())*(1. + GetTgl()*GetTgl()); | |
712 | sigma2 += fC00/r2*(1.- dy*dy/r2)*(1.- dy*dy/r2); | |
713 | sigma2 += kSigmaYV*kSigmaYV/r2; | |
714 | sigma2 += 0.25*fC44*fX*fX; | |
715 | Double_t eps2=sigma2/(fC22+sigma2), eps=TMath::Sqrt(eps2); | |
716 | if (10*r2*fC44<fC22) { | |
717 | fP2 = eps2*fP2 + (1-eps2)*par; | |
718 | fC22*=eps2; fC21*=eps; fC20*=eps; fC32*=eps; fC42*=eps; | |
719 | } | |
720 | ||
721 | par=0.5*fP4*dz/TMath::ASin(0.5*fP4*TMath::Sqrt(r2)); | |
722 | sigma2=theta2; | |
723 | sigma2 += fC11/r2+fC00*dy*dy*dz*dz/(r2*r2*r2); | |
724 | sigma2 += kSigmaZV*kSigmaZV/r2; | |
725 | eps2=sigma2/(fC33+sigma2); eps=TMath::Sqrt(eps2); | |
726 | Double_t tgl=fP3; | |
727 | fP3 = eps2*fP3 + (1-eps2)*par; | |
728 | fC33*=eps2; fC32*=eps; fC31*=eps; fC30*=eps; fC43*=eps; | |
729 | ||
730 | eps=TMath::Sqrt((1+fP3*fP3)/(1+tgl*tgl)); | |
731 | fP4*=eps; | |
732 | fC44*=eps*eps; fC43*=eps;fC42*=eps; fC41*=eps; fC40*=eps; | |
733 | ||
734 | if (!Invariant()) return 0; | |
735 | return 1; | |
736 | } | |
006b5f7f | 737 | */ |
14825d5a | 738 | void AliITStrackV2::ResetCovariance() { |
739 | //------------------------------------------------------------------ | |
740 | //This function makes a track forget its history :) | |
741 | //------------------------------------------------------------------ | |
742 | ||
743 | fC00*=10.; | |
744 | fC10=0.; fC11*=10.; | |
745 | fC20=0.; fC21=0.; fC22*=10.; | |
746 | fC30=0.; fC31=0.; fC32=0.; fC33*=10.; | |
747 | fC40=0.; fC41=0.; fC42=0.; fC43=0.; fC44*=10.; | |
748 | ||
749 | } | |
23efe5f1 | 750 | |
751 | void AliITStrackV2::CookdEdx(Double_t low, Double_t up) { | |
752 | //----------------------------------------------------------------- | |
a9a2d814 | 753 | // This function calculates dE/dX within the "low" and "up" cuts. |
754 | // Origin: Boris Batyunya, JINR, Boris.Batiounia@cern.ch | |
23efe5f1 | 755 | //----------------------------------------------------------------- |
23efe5f1 | 756 | // The clusters order is: SSD-2, SSD-1, SDD-2, SDD-1, SPD-2, SPD-1 |
c0dd5278 | 757 | |
758 | Int_t i; | |
759 | Int_t nc=0; | |
760 | for (i=0; i<GetNumberOfClusters(); i++) { | |
761 | Int_t idx=GetClusterIndex(i); | |
762 | idx=(idx&0xf0000000)>>28; | |
763 | if (idx>1) nc++; // Take only SSD and SDD | |
764 | } | |
23efe5f1 | 765 | |
a9a2d814 | 766 | Int_t swap;//stupid sorting |
23efe5f1 | 767 | do { |
768 | swap=0; | |
769 | for (i=0; i<nc-1; i++) { | |
770 | if (fdEdxSample[i]<=fdEdxSample[i+1]) continue; | |
771 | Float_t tmp=fdEdxSample[i]; | |
772 | fdEdxSample[i]=fdEdxSample[i+1]; fdEdxSample[i+1]=tmp; | |
773 | swap++; | |
774 | } | |
775 | } while (swap); | |
776 | ||
a9a2d814 | 777 | Int_t nl=Int_t(low*nc), nu=Int_t(up*nc); //b.b. to take two lowest dEdX |
778 | // values from four ones choose | |
779 | // nu=2 | |
23efe5f1 | 780 | Float_t dedx=0; |
a9a2d814 | 781 | for (i=nl; i<nu; i++) dedx += fdEdxSample[i]; |
c0dd5278 | 782 | if (nu-nl>0) dedx /= (nu-nl); |
23efe5f1 | 783 | |
23efe5f1 | 784 | SetdEdx(dedx); |
785 | } |