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46d29e70 | 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 | $Log$ | |
0e9c2ad5 | 18 | Revision 1.2 2000/10/06 16:49:46 cblume |
19 | Made Getters const | |
20 | ||
46d29e70 | 21 | Revision 1.1.2.1 2000/09/22 14:47:52 cblume |
22 | Add the tracking code | |
23 | ||
24 | */ | |
25 | ||
26 | #include <iostream.h> | |
27 | ||
28 | #include <TObject.h> | |
29 | ||
30 | #include "AliTRD.h" | |
46d29e70 | 31 | #include "AliTRDgeometry.h" |
32 | #include "AliTRDcluster.h" | |
33 | #include "AliTRDtrack.h" | |
34 | ||
35 | ClassImp(AliTRDtrack) | |
36 | ||
37 | ||
38 | //_____________________________________________________________________________ | |
39 | ||
40 | AliTRDtrack::AliTRDtrack(UInt_t index, const Double_t xx[5], | |
41 | const Double_t cc[15], Double_t xref, Double_t alpha) { | |
42 | //----------------------------------------------------------------- | |
43 | // This is the main track constructor. | |
44 | //----------------------------------------------------------------- | |
45 | fLab=-1; | |
46 | fChi2=0.; | |
47 | fdEdx=0.; | |
48 | ||
49 | fAlpha=alpha; | |
50 | fX=xref; | |
51 | ||
52 | fY=xx[0]; fZ=xx[1]; fC=xx[2]; fE=xx[3]; fT=xx[4]; | |
53 | ||
54 | fCyy=cc[0]; | |
55 | fCzy=cc[1]; fCzz=cc[2]; | |
56 | fCcy=cc[3]; fCcz=cc[4]; fCcc=cc[5]; | |
57 | fCey=cc[6]; fCez=cc[7]; fCec=cc[8]; fCee=cc[9]; | |
58 | fCty=cc[10]; fCtz=cc[11]; fCtc=cc[12]; fCte=cc[13]; fCtt=cc[14]; | |
59 | ||
60 | fN=0; | |
61 | fIndex[fN++]=index; | |
62 | } | |
63 | ||
64 | //_____________________________________________________________________________ | |
65 | AliTRDtrack::AliTRDtrack(const AliTRDtrack& t) { | |
66 | // | |
67 | // Copy constructor. | |
68 | // | |
69 | ||
70 | fLab=t.fLab; | |
71 | ||
72 | fChi2=t.fChi2; | |
73 | fdEdx=t.fdEdx; | |
74 | ||
75 | fAlpha=t.fAlpha; | |
76 | fX=t.fX; | |
77 | ||
78 | fY=t.fY; fZ=t.fZ; fC=t.fC; fE=t.fE; fT=t.fT; | |
79 | ||
80 | fCyy=t.fCyy; | |
81 | fCzy=t.fCzy; fCzz=t.fCzz; | |
82 | fCcy=t.fCcy; fCcz=t.fCcz; fCcc=t.fCcc; | |
83 | fCey=t.fCey; fCez=t.fCez; fCec=t.fCec; fCee=t.fCee; | |
84 | fCty=t.fCty; fCtz=t.fCtz; fCtc=t.fCtc; fCte=t.fCte; fCtt=t.fCtt; | |
85 | ||
86 | fN=t.fN; | |
87 | for (Int_t i=0; i<fN; i++) fIndex[i]=t.fIndex[i]; | |
88 | } | |
89 | ||
90 | //_____________________________________________________________________________ | |
91 | void AliTRDtrack::GetCovariance(Double_t cc[15]) const { | |
92 | cc[0]=fCyy; | |
93 | cc[1]=fCzy; cc[2]=fCzz; | |
94 | cc[3]=fCcy; cc[4]=fCcz; cc[5]=fCcc; | |
95 | cc[6]=fCey; cc[7]=fCez; cc[8]=fCec; cc[9]=fCee; | |
96 | cc[10]=fCty; cc[11]=fCtz; cc[12]=fCtc; cc[13]=fCte; cc[14]=fCtt; | |
97 | } | |
98 | ||
99 | //_____________________________________________________________________________ | |
100 | Int_t AliTRDtrack::Compare(TObject *o) { | |
101 | ||
102 | // Compares tracks according to their Y2 | |
103 | ||
104 | AliTRDtrack *t=(AliTRDtrack*)o; | |
105 | // Double_t co=t->GetSigmaY2(); | |
106 | // Double_t c =GetSigmaY2(); | |
107 | ||
108 | Double_t co=TMath::Abs(t->GetC()); | |
109 | Double_t c =TMath::Abs(GetC()); | |
110 | ||
111 | if (c>co) return 1; | |
112 | else if (c<co) return -1; | |
113 | return 0; | |
114 | } | |
115 | ||
116 | //_____________________________________________________________________________ | |
117 | Int_t AliTRDtrack::PropagateTo(Double_t xk,Double_t x0,Double_t rho,Double_t pm) | |
118 | { | |
119 | // Propagates a track of particle with mass=pm to a reference plane | |
120 | // defined by x=xk through media of density=rho and radiationLength=x0 | |
121 | ||
122 | if (TMath::Abs(fC*xk - fE) >= 0.99999) { | |
123 | if (fN>4) cerr<<fN<<" AliTRDtrack warning: Propagation failed !\n"; | |
124 | return 0; | |
125 | } | |
126 | ||
127 | Double_t x1=fX, x2=x1+(xk-x1), dx=x2-x1, y1=fY, z1=fZ; | |
128 | Double_t c1=fC*x1 - fE, r1=sqrt(1.- c1*c1); | |
129 | Double_t c2=fC*x2 - fE, r2=sqrt(1.- c2*c2); | |
130 | ||
131 | fY += dx*(c1+c2)/(r1+r2); | |
132 | fZ += dx*(c1+c2)/(c1*r2 + c2*r1)*fT; | |
133 | ||
134 | //f = F - 1 | |
135 | Double_t rr=r1+r2, cc=c1+c2, xx=x1+x2; | |
136 | Double_t f02= dx*(rr*xx + cc*(c1*x1/r1+c2*x2/r2))/(rr*rr); | |
137 | Double_t f03=-dx*(2*rr + cc*(c1/r1 + c2/r2))/(rr*rr); | |
138 | Double_t cr=c1*r2+c2*r1; | |
139 | Double_t f12= dx*fT*(cr*xx-cc*(r1*x2-c2*c1*x1/r1+r2*x1-c1*c2*x2/r2))/(cr*cr); | |
140 | Double_t f13=-dx*fT*(2*cr + cc*(c2*c1/r1-r1 + c1*c2/r2-r2))/(cr*cr); | |
141 | Double_t f14= dx*cc/cr; | |
142 | ||
143 | //b = C*ft | |
144 | Double_t b00=f02*fCcy + f03*fCey, b01=f12*fCcy + f13*fCey + f14*fCty; | |
145 | Double_t b10=f02*fCcz + f03*fCez, b11=f12*fCcz + f13*fCez + f14*fCtz; | |
146 | Double_t b20=f02*fCcc + f03*fCec, b21=f12*fCcc + f13*fCec + f14*fCtc; | |
147 | Double_t b30=f02*fCec + f03*fCee, b31=f12*fCec + f13*fCee + f14*fCte; | |
148 | Double_t b40=f02*fCtc + f03*fCte, b41=f12*fCtc + f13*fCte + f14*fCtt; | |
149 | ||
150 | //a = f*b = f*C*ft | |
151 | Double_t a00=f02*b20+f03*b30,a01=f02*b21+f03*b31,a11=f12*b21+f13*b31+f14*b41; | |
152 | ||
153 | //F*C*Ft = C + (a + b + bt) | |
154 | fCyy += a00 + 2*b00; | |
155 | fCzy += a01 + b01 + b10; | |
156 | fCcy += b20; | |
157 | fCey += b30; | |
158 | fCty += b40; | |
159 | fCzz += a11 + 2*b11; | |
160 | fCcz += b21; | |
161 | fCez += b31; | |
162 | fCtz += b41; | |
163 | ||
164 | fX=x2; | |
165 | ||
166 | ||
167 | //Multiple scattering ****************** | |
168 | ||
169 | Double_t d=sqrt((x1-fX)*(x1-fX)+(y1-fY)*(y1-fY)+(z1-fZ)*(z1-fZ)); | |
170 | Double_t p2=GetPt()*GetPt()*(1.+fT*fT); | |
171 | Double_t beta2=p2/(p2 + pm*pm); | |
172 | ||
173 | Double_t ey=fC*fX - fE, ez=fT; | |
174 | Double_t xz=fC*ez, zz1=ez*ez+1, xy=fE+ey; | |
175 | ||
176 | Double_t theta2=14.1*14.1/(beta2*p2*1e6)*d/x0*rho; | |
177 | fCcc += xz*xz*theta2; | |
178 | fCec += xz*ez*xy*theta2; | |
179 | fCtc += xz*zz1*theta2; | |
180 | fCee += (2*ey*ez*ez*fE+1-ey*ey+ez*ez+fE*fE*ez*ez)*theta2; | |
181 | fCte += ez*zz1*xy*theta2; | |
182 | fCtt += zz1*zz1*theta2; | |
183 | ||
184 | ||
185 | //Energy losses************************ | |
186 | ||
187 | Double_t dE=0.153e-3/beta2*(log(5940*beta2/(1-beta2)) - beta2)*d*rho; | |
188 | if (x1 < x2) dE=-dE; | |
189 | fC*=(1.- sqrt(p2+pm*pm)/p2*dE); | |
190 | //fE*=(1.- sqrt(p2+pm*pm)/p2*dE); | |
191 | ||
192 | return 1; | |
193 | ||
194 | } | |
195 | ||
196 | ||
197 | //_____________________________________________________________________________ | |
198 | void AliTRDtrack::PropagateToVertex(Double_t x0,Double_t rho,Double_t pm) | |
199 | { | |
200 | // This function propagates tracks to the "vertex". | |
201 | ||
202 | Double_t c=fC*fX - fE; | |
203 | Double_t tgf=-fE/(fC*fY + sqrt(1-c*c)); | |
204 | Double_t snf=tgf/sqrt(1.+ tgf*tgf); | |
205 | Double_t xv=(fE+snf)/fC; | |
206 | PropagateTo(xv,x0,rho,pm); | |
207 | } | |
208 | ||
209 | ||
210 | //_____________________________________________________________________________ | |
211 | void AliTRDtrack::Update(const AliTRDcluster *c, Double_t chisq, UInt_t index) | |
212 | { | |
213 | // Assignes found cluster to the track and updates track information | |
214 | ||
215 | Double_t r00=c->GetSigmaY2(), r01=0., r11=c->GetSigmaZ2()*12; | |
216 | r00+=fCyy; r01+=fCzy; r11+=fCzz; | |
217 | Double_t det=r00*r11 - r01*r01; | |
218 | Double_t tmp=r00; r00=r11/det; r11=tmp/det; r01=-r01/det; | |
219 | ||
220 | Double_t k00=fCyy*r00+fCzy*r01, k01=fCyy*r01+fCzy*r11; | |
221 | Double_t k10=fCzy*r00+fCzz*r01, k11=fCzy*r01+fCzz*r11; | |
222 | Double_t k20=fCcy*r00+fCcz*r01, k21=fCcy*r01+fCcz*r11; | |
223 | Double_t k30=fCey*r00+fCez*r01, k31=fCey*r01+fCez*r11; | |
224 | Double_t k40=fCty*r00+fCtz*r01, k41=fCty*r01+fCtz*r11; | |
225 | ||
226 | Double_t dy=c->GetY() - fY, dz=c->GetZ() - fZ; | |
227 | Double_t cur=fC + k20*dy + k21*dz, eta=fE + k30*dy + k31*dz; | |
228 | if (TMath::Abs(cur*fX-eta) >= 0.99999) { | |
229 | if (fN>4) cerr<<fN<<" AliTRDtrack warning: Filtering failed !\n"; | |
230 | return; | |
231 | } | |
232 | ||
233 | fY += k00*dy + k01*dz; | |
234 | fZ += k10*dy + k11*dz; | |
235 | fC = cur; | |
236 | fE = eta; | |
237 | fT += k40*dy + k41*dz; | |
238 | ||
239 | Double_t c01=fCzy, c02=fCcy, c03=fCey, c04=fCty; | |
240 | Double_t c12=fCcz, c13=fCez, c14=fCtz; | |
241 | ||
242 | fCyy-=k00*fCyy+k01*fCzy; fCzy-=k00*c01+k01*fCzz; | |
243 | fCcy-=k00*c02+k01*c12; fCey-=k00*c03+k01*c13; | |
244 | fCty-=k00*c04+k01*c14; | |
245 | ||
246 | fCzz-=k10*c01+k11*fCzz; | |
247 | fCcz-=k10*c02+k11*c12; fCez-=k10*c03+k11*c13; | |
248 | fCtz-=k10*c04+k11*c14; | |
249 | ||
250 | fCcc-=k20*c02+k21*c12; fCec-=k20*c03+k21*c13; | |
251 | fCtc-=k20*c04+k21*c14; | |
252 | ||
253 | fCee-=k30*c03+k31*c13; | |
254 | fCte-=k30*c04+k31*c14; | |
255 | ||
256 | fCtt-=k40*c04+k41*c14; | |
257 | ||
258 | fIndex[fN++]=index; | |
259 | fChi2 += chisq; | |
260 | ||
261 | // cerr<<"in update: fIndex["<<fN<<"] = "<<index<<endl; | |
262 | } | |
263 | ||
264 | //_____________________________________________________________________________ | |
265 | Int_t AliTRDtrack::Rotate(Double_t alpha) | |
266 | { | |
267 | // Rotates track parameters in R*phi plane | |
268 | ||
269 | fAlpha += alpha; | |
270 | ||
271 | Double_t x1=fX, y1=fY; | |
272 | Double_t ca=cos(alpha), sa=sin(alpha); | |
273 | Double_t r1=fC*fX - fE; | |
274 | ||
275 | fX = x1*ca + y1*sa; | |
276 | fY=-x1*sa + y1*ca; | |
277 | fE=fE*ca + (fC*y1 + sqrt(1.- r1*r1))*sa; | |
278 | ||
279 | Double_t r2=fC*fX - fE; | |
280 | if (TMath::Abs(r2) >= 0.99999) { | |
281 | if (fN>4) cerr<<fN<<" AliTRDtrack warning: Rotation failed !\n"; | |
282 | return 0; | |
283 | } | |
284 | ||
285 | Double_t y0=fY + sqrt(1.- r2*r2)/fC; | |
286 | if ((fY-y0)*fC >= 0.) { | |
287 | if (fN>4) cerr<<fN<<" AliTRDtrack warning: Rotation failed !!!\n"; | |
288 | return 0; | |
289 | } | |
290 | ||
291 | //f = F - 1 | |
292 | Double_t f00=ca-1, f32=(y1 - r1*x1/sqrt(1.- r1*r1))*sa, | |
293 | f30=fC*sa, f33=(ca + sa*r1/sqrt(1.- r1*r1))-1; | |
294 | ||
295 | //b = C*ft | |
296 | Double_t b00=fCyy*f00, b03=fCyy*f30+fCcy*f32+fCey*f33; | |
297 | Double_t b10=fCzy*f00, b13=fCzy*f30+fCcz*f32+fCez*f33; | |
298 | Double_t b20=fCcy*f00, b23=fCcy*f30+fCcc*f32+fCec*f33; | |
299 | Double_t b30=fCey*f00, b33=fCey*f30+fCec*f32+fCee*f33; | |
300 | Double_t b40=fCty*f00, b43=fCty*f30+fCtc*f32+fCte*f33; | |
301 | ||
302 | //a = f*b = f*C*ft | |
303 | Double_t a00=f00*b00, a03=f00*b03, a33=f30*b03+f32*b23+f33*b33; | |
304 | ||
305 | // *** Double_t dy2=fCyy; | |
306 | ||
307 | //F*C*Ft = C + (a + b + bt) | |
308 | fCyy += a00 + 2*b00; | |
309 | fCzy += b10; | |
310 | fCcy += b20; | |
311 | fCey += a03+b30+b03; | |
312 | fCty += b40; | |
313 | fCez += b13; | |
314 | fCec += b23; | |
315 | fCee += a33 + 2*b33; | |
316 | fCte += b43; | |
317 | ||
318 | // *** fCyy+=dy2*sa*sa*r1*r1/(1.- r1*r1); | |
319 | // *** fCzz+=d2y*sa*sa*fT*fT/(1.- r1*r1); | |
320 | ||
321 | return 1; | |
322 | } | |
323 | ||
324 | ||
325 | ||
326 | ||
327 | //_____________________________________________________________________________ | |
328 | Double_t AliTRDtrack::GetPredictedChi2(const AliTRDcluster *c) const | |
329 | { | |
330 | Double_t r00=c->GetSigmaY2(), r01=0., r11=c->GetSigmaZ2()*12; | |
331 | r00+=fCyy; r01+=fCzy; r11+=fCzz; | |
332 | ||
333 | Double_t det=r00*r11 - r01*r01; | |
334 | if (TMath::Abs(det) < 1.e-10) { | |
335 | if (fN>4) cerr<<fN<<" AliTRDtrack warning: Singular matrix !\n"; | |
336 | return 1e10; | |
337 | } | |
338 | Double_t tmp=r00; r00=r11; r11=tmp; r01=-r01; | |
339 | ||
340 | Double_t dy=c->GetY() - fY, dz=c->GetZ() - fZ; | |
341 | ||
342 | return (dy*r00*dy + 2*r01*dy*dz + dz*r11*dz)/det; | |
343 | } | |
344 | ||
345 | ||
346 | //_________________________________________________________________________ | |
347 | void AliTRDtrack::GetPxPyPz(Double_t& px, Double_t& py, Double_t& pz) const | |
348 | { | |
349 | // Returns reconstructed track momentum in the global system. | |
350 | ||
351 | Double_t pt=TMath::Abs(GetPt()); // GeV/c | |
352 | Double_t r=fC*fX-fE; | |
353 | Double_t y0=fY + sqrt(1.- r*r)/fC; | |
354 | px=-pt*(fY-y0)*fC; //cos(phi); | |
355 | py=-pt*(fE-fX*fC); //sin(phi); | |
356 | pz=pt*fT; | |
357 | Double_t tmp=px*TMath::Cos(fAlpha) - py*TMath::Sin(fAlpha); | |
358 | py=px*TMath::Sin(fAlpha) + py*TMath::Cos(fAlpha); | |
359 | px=tmp; | |
360 | ||
361 | } | |
362 | ||
363 | //____________________________________________________________________________ | |
364 | void AliTRDtrack::Streamer(TBuffer &R__b) | |
365 | { | |
366 | if (R__b.IsReading()) { | |
367 | Version_t R__v = R__b.ReadVersion(); if (R__v) { } | |
368 | TObject::Streamer(R__b); | |
369 | R__b >> fLab; | |
370 | R__b >> fChi2; | |
371 | R__b >> fdEdx; | |
372 | R__b >> fAlpha; | |
373 | R__b >> fX; | |
374 | R__b >> fY; | |
375 | R__b >> fZ; | |
376 | R__b >> fC; | |
377 | R__b >> fE; | |
378 | R__b >> fT; | |
379 | R__b >> fCyy; | |
380 | R__b >> fCzy; | |
381 | R__b >> fCzz; | |
382 | R__b >> fCcy; | |
383 | R__b >> fCcz; | |
384 | R__b >> fCcc; | |
385 | R__b >> fCey; | |
386 | R__b >> fCez; | |
387 | R__b >> fCec; | |
388 | R__b >> fCee; | |
389 | R__b >> fCty; | |
390 | R__b >> fCtz; | |
391 | R__b >> fCtc; | |
392 | R__b >> fCte; | |
393 | R__b >> fCtt; | |
394 | R__b >> fN; | |
395 | for (Int_t i=0; i<fN; i++) R__b >> fIndex[i]; | |
396 | } else { | |
397 | R__b.WriteVersion(AliTRDtrack::IsA()); | |
398 | TObject::Streamer(R__b); | |
399 | R__b << fLab; | |
400 | R__b << fChi2; | |
401 | R__b << fdEdx; | |
402 | R__b << fAlpha; | |
403 | R__b << fX; | |
404 | R__b << fY; | |
405 | R__b << fZ; | |
406 | R__b << fC; | |
407 | R__b << fE; | |
408 | R__b << fT; | |
409 | R__b << fCyy; | |
410 | R__b << fCzy; | |
411 | R__b << fCzz; | |
412 | R__b << fCcy; | |
413 | R__b << fCcz; | |
414 | R__b << fCcc; | |
415 | R__b << fCey; | |
416 | R__b << fCez; | |
417 | R__b << fCec; | |
418 | R__b << fCee; | |
419 | R__b << fCty; | |
420 | R__b << fCtz; | |
421 | R__b << fCtc; | |
422 | R__b << fCte; | |
423 | R__b << fCtt; | |
424 | R__b << fN; | |
425 | for (Int_t i=0; i<fN; i++) R__b << fIndex[i]; | |
426 | } | |
427 | } | |
428 | ||
429 | //_____________________________________________________________________________ | |
430 | void AliTRDseed::CookdEdx(Double_t low, Double_t up) { | |
431 | ||
432 | // Calculates dE/dX within the "low" and "up" cuts. | |
433 | ||
434 | Int_t i; | |
435 | Int_t nc=this->GetNclusters(); | |
436 | ||
437 | Int_t swap;//stupid sorting | |
438 | do { | |
439 | swap=0; | |
440 | for (i=0; i<nc-1; i++) { | |
441 | if (fdEdx[i]<=fdEdx[i+1]) continue; | |
442 | Float_t tmp=fdEdx[i]; fdEdx[i]=fdEdx[i+1]; fdEdx[i+1]=tmp; | |
443 | swap++; | |
444 | } | |
445 | } while (swap); | |
446 | ||
447 | Int_t nl=Int_t(low*nc), nu=Int_t(up*nc); | |
448 | Float_t dedx=0; | |
449 | for (i=nl; i<=nu; i++) dedx += fdEdx[i]; | |
450 | dedx /= (nu-nl+1); | |
451 | SetdEdx(dedx); | |
452 | } | |
453 |