]>
Commit | Line | Data |
---|---|---|
6d4f1901 | 1 | //$Id$ |
2 | ||
2d04dcbf | 3 | // Author: Anders Vestbo <mailto:vestbo$fi.uib.no>, Uli Frankenfeld <mailto:franken@fi.uib.no> |
4 | //*-- Copyright © ASV | |
108615fc | 5 | |
108615fc | 6 | |
7 | #include "AliL3RootTypes.h" | |
8 | ||
9 | #include "AliL3Logging.h" | |
10 | #include "AliL3Track.h" | |
0391971c | 11 | #include "AliL3Transform.h" |
6d4f1901 | 12 | #include "AliL3Vertex.h" |
108615fc | 13 | #include <math.h> |
14 | ||
2d04dcbf | 15 | //_____________________________________________________________ |
16 | // AliL3Track | |
17 | // | |
18 | // Track base class | |
02cb36b2 | 19 | //Begin_Html |
20 | /* | |
21 | <img src="track_coordinates.gif"> | |
22 | */ | |
23 | //End_Html | |
0391971c | 24 | |
108615fc | 25 | ClassImp(AliL3Track) |
26 | ||
27 | Float_t AliL3Track::BFACT = 0.0029980; | |
108615fc | 28 | Double_t AliL3Track::pi=3.14159265358979323846; |
29 | ||
30 | AliL3Track::AliL3Track() | |
31 | { | |
32 | //Constructor | |
33 | ||
34 | fNHits = 0; | |
35 | fMCid = -1; | |
36 | fKappa=0; | |
37 | fRadius=0; | |
38 | fCenterX=0; | |
39 | fCenterY=0; | |
40 | ComesFromMainVertex(false); | |
41 | fQ = 0; | |
42 | fPhi0=0; | |
43 | fPsi=0; | |
44 | fR0=0; | |
45 | fTanl=0; | |
46 | fZ0=0; | |
47 | fPt=0; | |
48 | fLength=0; | |
49 | fIsLocal=true; | |
50 | fRowRange[0]=0; | |
51 | fRowRange[1]=0; | |
ae97a0b9 | 52 | memset(fHitNumbers,0,176*sizeof(UInt_t)); |
108615fc | 53 | } |
54 | ||
55 | void AliL3Track::Set(AliL3Track *tpt){ | |
56 | ||
3a735e00 | 57 | SetRowRange(tpt->GetFirstRow(),tpt->GetLastRow()); |
58 | SetPhi0(tpt->GetPhi0()); | |
59 | SetKappa(tpt->GetKappa()); | |
60 | SetNHits(tpt->GetNHits()); | |
61 | SetFirstPoint(tpt->GetFirstPointX(),tpt->GetFirstPointY(),tpt->GetFirstPointZ()); | |
62 | SetLastPoint(tpt->GetLastPointX(),tpt->GetLastPointY(),tpt->GetLastPointZ()); | |
63 | SetPt(tpt->GetPt()); | |
64 | SetPsi(tpt->GetPsi()); | |
65 | SetTgl(tpt->GetTgl()); | |
66 | SetCharge(tpt->GetCharge()); | |
67 | SetHits(tpt->GetNHits(),(UInt_t *)tpt->GetHitNumbers()); | |
108615fc | 68 | } |
69 | ||
203925a9 | 70 | Int_t AliL3Track::Compare(const AliL3Track *track) const |
71 | { | |
72 | if(track->GetNHits() < GetNHits()) return 1; | |
73 | if(track->GetNHits() > GetNHits()) return -1; | |
74 | return 0; | |
75 | } | |
108615fc | 76 | |
77 | AliL3Track::~AliL3Track() | |
78 | { | |
203925a9 | 79 | //Nothing to do |
108615fc | 80 | } |
81 | ||
82 | Double_t AliL3Track::GetP() const | |
83 | { | |
203925a9 | 84 | // Returns total momentum. |
108615fc | 85 | return fabs(GetPt())*sqrt(1. + GetTgl()*GetTgl()); |
108615fc | 86 | } |
87 | ||
88 | Double_t AliL3Track::GetPseudoRapidity() const | |
89 | { | |
90 | return 0.5 * log((GetP() + GetPz()) / (GetP() - GetPz())); | |
91 | } | |
eeddc64d | 92 | |
203925a9 | 93 | /* |
108615fc | 94 | Double_t AliL3Track::GetEta() const |
95 | { | |
96 | return GetPseudoRapidity(); | |
97 | } | |
203925a9 | 98 | */ |
eeddc64d | 99 | |
108615fc | 100 | Double_t AliL3Track::GetRapidity() const |
101 | { | |
102 | Double_t m_pi = 0.13957; | |
103 | return 0.5 * log((m_pi + GetPz()) / (m_pi - GetPz())); | |
104 | } | |
105 | ||
203925a9 | 106 | void AliL3Track::Rotate(Int_t slice,Bool_t tolocal) |
0391971c | 107 | { |
0391971c | 108 | //Rotate track to global parameters |
203925a9 | 109 | //If flag tolocal is set, the track is rotated |
110 | //to local coordinates. | |
0391971c | 111 | |
0391971c | 112 | |
113 | Float_t psi[1] = {GetPsi()}; | |
203925a9 | 114 | if(!tolocal) |
494fad94 | 115 | AliL3Transform::Local2GlobalAngle(psi,slice); |
203925a9 | 116 | else |
494fad94 | 117 | AliL3Transform::Global2LocalAngle(psi,slice); |
0391971c | 118 | SetPsi(psi[0]); |
119 | Float_t first[3]; | |
120 | first[0] = GetFirstPointX(); | |
121 | first[1] = GetFirstPointY(); | |
122 | first[2] = GetFirstPointZ(); | |
203925a9 | 123 | if(!tolocal) |
494fad94 | 124 | AliL3Transform::Local2Global(first,slice); |
203925a9 | 125 | else |
494fad94 | 126 | AliL3Transform::Global2Local(first,slice,kTRUE); |
203925a9 | 127 | |
0391971c | 128 | SetFirstPoint(first[0],first[1],first[2]); |
129 | Float_t last[3]; | |
130 | last[0] = GetLastPointX(); | |
131 | last[1] = GetLastPointY(); | |
132 | last[2] = GetLastPointZ(); | |
203925a9 | 133 | if(!tolocal) |
494fad94 | 134 | AliL3Transform::Local2Global(last,slice); |
203925a9 | 135 | else |
494fad94 | 136 | AliL3Transform::Global2Local(last,slice,kTRUE); |
0391971c | 137 | SetLastPoint(last[0],last[1],last[2]); |
203925a9 | 138 | |
6d4f1901 | 139 | Float_t center[3] = {GetCenterX(),GetCenterY(),0}; |
140 | if(!tolocal) | |
494fad94 | 141 | AliL3Transform::Local2Global(center,slice); |
6d4f1901 | 142 | else |
494fad94 | 143 | AliL3Transform::Global2Local(center,slice,kTRUE); |
6d4f1901 | 144 | SetCenterX(center[0]); |
145 | SetCenterY(center[1]); | |
146 | ||
203925a9 | 147 | if(!tolocal) |
148 | fIsLocal=kFALSE; | |
149 | else | |
150 | fIsLocal=kTRUE; | |
0391971c | 151 | } |
152 | ||
108615fc | 153 | void AliL3Track::CalculateHelix(){ |
eeddc64d | 154 | //Calculate Radius, CenterX and CenterY from Psi, X0, Y0 |
108615fc | 155 | // |
156 | ||
ef79795d | 157 | fRadius = fPt / (BFACT*AliL3Transform::GetBField()); |
3ceb3fe1 | 158 | if(fRadius) fKappa = -fQ*1./fRadius; |
108615fc | 159 | else fRadius = 999999; //just zero |
160 | Double_t trackPhi0 = fPsi + fQ *0.5 * pi; | |
161 | ||
162 | fCenterX = fFirstPoint[0] - fRadius * cos(trackPhi0); | |
163 | fCenterY = fFirstPoint[1] - fRadius * sin(trackPhi0); | |
164 | } | |
165 | ||
2d04dcbf | 166 | Double_t AliL3Track::GetCrossingAngle(Int_t padrow) |
0391971c | 167 | { |
168 | //Calculate the crossing angle between track and given padrow. | |
2d04dcbf | 169 | |
0391971c | 170 | if(!IsLocal()) |
171 | { | |
172 | printf("Track is not given in local coordinates\n"); | |
173 | return 0; | |
174 | } | |
2d04dcbf | 175 | |
0391971c | 176 | Float_t xyz[3]; |
177 | if(!GetCrossingPoint(padrow,xyz)) | |
178 | printf("AliL3HoughTrack::GetCrossingPoint : Track does not cross line!!\n"); | |
179 | ||
180 | //Take the dot product of the tangent vector of the track, and | |
181 | //vector perpendicular to the padrow. | |
dab230b2 | 182 | //In order to do this, we need the tangent vector to the track at the |
183 | //point. This is done by rotating the radius vector by 90 degrees; | |
184 | //rotation matrix: ( 0 1 ) | |
185 | // ( -1 0 ) | |
0391971c | 186 | |
187 | Double_t tangent[2]; | |
0391971c | 188 | tangent[0] = -1.*(xyz[1] - GetCenterY())/GetRadius(); |
dab230b2 | 189 | tangent[1] = (xyz[0] - GetCenterX())/GetRadius(); |
190 | ||
0391971c | 191 | Double_t perp_padrow[2] = {1,0}; //locally in slice |
192 | ||
193 | Double_t cos_beta = fabs(tangent[0]*perp_padrow[0] + tangent[1]*perp_padrow[1]); | |
194 | return acos(cos_beta); | |
0391971c | 195 | } |
196 | ||
2d04dcbf | 197 | Bool_t AliL3Track::GetCrossingPoint(Int_t padrow,Float_t *xyz) |
0391971c | 198 | { |
199 | //Assumes the track is given in local coordinates | |
200 | ||
0391971c | 201 | if(!IsLocal()) |
202 | { | |
203 | printf("GetCrossingPoint: Track is given on global coordinates\n"); | |
204 | return false; | |
205 | } | |
206 | ||
494fad94 | 207 | Double_t xHit = AliL3Transform::Row2X(padrow); |
0391971c | 208 | |
209 | xyz[0] = xHit; | |
210 | Double_t aa = (xHit - GetCenterX())*(xHit - GetCenterX()); | |
211 | Double_t r2 = GetRadius()*GetRadius(); | |
212 | if(aa > r2) | |
213 | return false; | |
214 | ||
215 | Double_t aa2 = sqrt(r2 - aa); | |
216 | Double_t y1 = GetCenterY() + aa2; | |
217 | Double_t y2 = GetCenterY() - aa2; | |
218 | xyz[1] = y1; | |
219 | if(fabs(y2) < fabs(y1)) xyz[1] = y2; | |
220 | ||
221 | Double_t yHit = xyz[1]; | |
222 | Double_t angle1 = atan2((yHit - GetCenterY()),(xHit - GetCenterX())); | |
9ca67380 | 223 | if(angle1 < 0) angle1 += 2.*AliL3Transform::Pi(); |
0391971c | 224 | Double_t angle2 = atan2((GetFirstPointY() - GetCenterY()),(GetFirstPointX() - GetCenterX())); |
9ca67380 | 225 | if(angle2 < 0) angle2 += 2.*AliL3Transform::Pi(); |
0391971c | 226 | Double_t diff_angle = angle1 - angle2; |
9ca67380 | 227 | diff_angle = fmod(diff_angle,2*AliL3Transform::Pi()); |
228 | if((GetCharge()*diff_angle) > 0) diff_angle = diff_angle - GetCharge()*2.*AliL3Transform::Pi(); | |
0391971c | 229 | Double_t s_tot = fabs(diff_angle)*GetRadius(); |
230 | Double_t zHit = GetFirstPointZ() + s_tot*GetTgl(); | |
231 | xyz[2] = zHit; | |
232 | ||
0391971c | 233 | return true; |
234 | } | |
235 | ||
236 | ||
6d4f1901 | 237 | Bool_t AliL3Track::CalculateReferencePoint(Double_t angle,Double_t radius){ |
9ca67380 | 238 | // Global coordinate: crossing point with y = ax+ b; a=tan(angle-AliL3Transform::Pi()/2); |
108615fc | 239 | // |
eeddc64d | 240 | const Double_t rr=radius;//132; //position of reference plane |
241 | const Double_t xr = cos(angle) * rr; | |
242 | const Double_t yr = sin(angle) * rr; | |
6d4f1901 | 243 | |
108615fc | 244 | Double_t a = tan(angle-pi/2); |
245 | Double_t b = yr - a * xr; | |
246 | ||
247 | Double_t pp=(fCenterX+a*fCenterY-a*b)/(1+pow(a,2)); | |
248 | Double_t qq=(pow(fCenterX,2)+pow(fCenterY,2)-2*fCenterY*b+pow(b,2)-pow(fRadius,2))/(1+pow(a,2)); | |
249 | ||
250 | Double_t racine = pp*pp-qq; | |
251 | if(racine<0) return IsPoint(kFALSE); //no Point | |
252 | ||
253 | Double_t rootRacine = sqrt(racine); | |
254 | Double_t x0 = pp+rootRacine; | |
255 | Double_t x1 = pp-rootRacine; | |
256 | Double_t y0 = a*x0 + b; | |
257 | Double_t y1 = a*x1 + b; | |
258 | ||
259 | Double_t diff0 = sqrt(pow(x0-xr,2)+pow(y0-yr,2)); | |
260 | Double_t diff1 = sqrt(pow(x1-xr,2)+pow(y1-yr,2)); | |
261 | ||
262 | if(diff0<diff1){ | |
263 | fPoint[0]=x0; | |
264 | fPoint[1]=y0; | |
265 | } | |
266 | else{ | |
267 | fPoint[0]=x1; | |
268 | fPoint[1]=y1; | |
269 | } | |
270 | ||
271 | Double_t pointPhi0 = atan2(fPoint[1]-fCenterY,fPoint[0]-fCenterX); | |
272 | Double_t trackPhi0 = atan2(fFirstPoint[1]-fCenterY,fFirstPoint[0]-fCenterX); | |
273 | if(fabs(trackPhi0-pointPhi0)>pi){ | |
274 | if(trackPhi0<pointPhi0) trackPhi0 += 2*pi; | |
275 | else pointPhi0 += 2*pi; | |
276 | } | |
277 | Double_t stot = -fQ * (pointPhi0-trackPhi0) * fRadius ; | |
278 | fPoint[2] = fFirstPoint[2] + stot * fTanl; | |
279 | ||
280 | fPointPsi = pointPhi0 - fQ * 0.5 * pi; | |
281 | if(fPointPsi<0.) fPointPsi+= 2*pi; | |
282 | fPointPsi = fmod(fPointPsi, 2*pi); | |
283 | ||
284 | return IsPoint(kTRUE); | |
285 | } | |
286 | ||
287 | Bool_t AliL3Track::CalculateEdgePoint(Double_t angle){ | |
288 | // Global coordinate: crossing point with y = ax; a=tan(angle); | |
289 | // | |
290 | Double_t rmin=80; //min Radius of TPC | |
291 | Double_t rmax=260; //max Radius of TPC | |
292 | ||
293 | Double_t a = tan(angle); | |
294 | Double_t pp=(fCenterX+a*fCenterY)/(1+pow(a,2)); | |
295 | Double_t qq=(pow(fCenterX,2)+pow(fCenterY,2)-pow(fRadius,2))/(1+pow(a,2)); | |
296 | Double_t racine = pp*pp-qq; | |
297 | if(racine<0) return IsPoint(kFALSE); //no Point | |
298 | Double_t rootRacine = sqrt(racine); | |
299 | Double_t x0 = pp+rootRacine; | |
300 | Double_t x1 = pp-rootRacine; | |
301 | Double_t y0 = a*x0; | |
302 | Double_t y1 = a*x1; | |
303 | ||
304 | Double_t r0 = sqrt(pow(x0,2)+pow(y0,2)); | |
305 | Double_t r1 = sqrt(pow(x1,2)+pow(y1,2)); | |
306 | //find the right crossing point: | |
307 | //inside the TPC modules | |
308 | Bool_t ok0 = kFALSE; | |
309 | Bool_t ok1 = kFALSE; | |
472d9e24 | 310 | |
108615fc | 311 | if(r0>rmin&&r0<rmax){ |
312 | Double_t da=atan2(y0,x0); | |
472d9e24 | 313 | if(da<0) da+=2*pi; |
108615fc | 314 | if(fabs(da-angle)<0.5) |
315 | ok0 = kTRUE; | |
316 | } | |
317 | if(r1>rmin&&r1<rmax){ | |
472d9e24 | 318 | Double_t da=atan2(y1,x1); |
319 | if(da<0) da+=2*pi; | |
108615fc | 320 | if(fabs(da-angle)<0.5) |
321 | ok1 = kTRUE; | |
322 | } | |
323 | if(!(ok0||ok1)) return IsPoint(kFALSE); //no Point | |
324 | ||
325 | if(ok0&&ok1){ | |
326 | Double_t diff0 = sqrt(pow(fFirstPoint[0]-x0,2)+pow(fFirstPoint[1]-y0,2)); | |
327 | Double_t diff1 = sqrt(pow(fFirstPoint[0]-x1,2)+pow(fFirstPoint[1]-y1,2)); | |
328 | if(diff0<diff1) ok1 = kFALSE; //use ok0 | |
329 | else ok0 = kFALSE; //use ok1 | |
330 | } | |
331 | if(ok0){fPoint[0]=x0; fPoint[1]=y0;} | |
332 | else {fPoint[0]=x1; fPoint[1]=y1;} | |
333 | ||
334 | Double_t pointPhi0 = atan2(fPoint[1]-fCenterY,fPoint[0]-fCenterX); | |
335 | Double_t trackPhi0 = atan2(fFirstPoint[1]-fCenterY,fFirstPoint[0]-fCenterX); | |
336 | if(fabs(trackPhi0-pointPhi0)>pi){ | |
337 | if(trackPhi0<pointPhi0) trackPhi0 += 2*pi; | |
338 | else pointPhi0 += 2*pi; | |
339 | } | |
340 | Double_t stot = -fQ * (pointPhi0-trackPhi0) * fRadius ; | |
341 | fPoint[2] = fFirstPoint[2] + stot * fTanl; | |
342 | ||
343 | fPointPsi = pointPhi0 - fQ * 0.5 * pi; | |
344 | if(fPointPsi<0.) fPointPsi+= 2*pi; | |
345 | fPointPsi = fmod(fPointPsi, 2*pi); | |
346 | ||
347 | return IsPoint(kTRUE); | |
348 | } | |
349 | ||
350 | Bool_t AliL3Track::CalculatePoint(Double_t xplane){ | |
351 | // Local coordinate: crossing point with x plane | |
352 | // | |
353 | Double_t racine = pow(fRadius,2)-pow(xplane-fCenterX,2); | |
354 | if(racine<0) return IsPoint(kFALSE); | |
355 | Double_t rootRacine = sqrt(racine); | |
356 | ||
357 | Double_t y0 = fCenterY + rootRacine; | |
358 | Double_t y1 = fCenterY - rootRacine; | |
359 | //Double_t diff0 = sqrt(pow(fFirstPoint[0]-xplane)+pow(fFirstPoint[1]-y0)); | |
360 | //Double_t diff1 = sqrt(pow(fFirstPoint[0]-xplane)+pow(fFirstPoint[1]-y1)); | |
361 | Double_t diff0 = fabs(y0-fFirstPoint[1]); | |
362 | Double_t diff1 = fabs(y1-fFirstPoint[1]); | |
363 | ||
364 | fPoint[0]=xplane; | |
365 | if(diff0<diff1) fPoint[1]=y0; | |
366 | else fPoint[1]=y1; | |
367 | ||
368 | Double_t pointPhi0 = atan2(fPoint[1]-fCenterY,fPoint[0]-fCenterX); | |
369 | Double_t trackPhi0 = atan2(fFirstPoint[1]-fCenterY,fFirstPoint[0]-fCenterX); | |
370 | if(fabs(trackPhi0-pointPhi0)>pi){ | |
371 | if(trackPhi0<pointPhi0) trackPhi0 += 2*pi; | |
372 | else pointPhi0 += 2*pi; | |
373 | } | |
374 | Double_t stot = -fQ * (pointPhi0-trackPhi0) * fRadius ; | |
375 | fPoint[2] = fFirstPoint[2] + stot * fTanl; | |
376 | ||
377 | fPointPsi = pointPhi0 - fQ * 0.5 * pi; | |
378 | if(fPointPsi<0.) fPointPsi+= 2*pi; | |
379 | fPointPsi = fmod(fPointPsi, 2*pi); | |
380 | ||
381 | return IsPoint(kTRUE); | |
382 | } | |
383 | ||
6d4f1901 | 384 | void AliL3Track::GetClosestPoint(AliL3Vertex *vertex,Double_t &closest_x,Double_t &closest_y,Double_t &closest_z) |
385 | { | |
386 | //Calculate the point of closest approach to the vertex | |
387 | ||
388 | ||
389 | Double_t xc = GetCenterX() - vertex->GetX();//Shift the center of curvature with respect to the vertex | |
390 | Double_t yc = GetCenterY() - vertex->GetY(); | |
391 | ||
392 | Double_t dist_x1 = xc*(1 + GetRadius()/sqrt(xc*xc + yc*yc)); | |
393 | Double_t dist_y1 = yc*(1 + GetRadius()/sqrt(xc*xc + yc*yc)); | |
394 | Double_t distance1 = sqrt(dist_x1*dist_x1 + dist_y1*dist_y1); | |
395 | ||
396 | Double_t dist_x2 = xc*(1 - GetRadius()/sqrt(xc*xc + yc*yc)); | |
397 | Double_t dist_y2 = yc*(1 - GetRadius()/sqrt(xc*xc + yc*yc)); | |
398 | Double_t distance2 = sqrt(dist_x2*dist_x2 + dist_y2*dist_y2); | |
399 | ||
400 | //Choose the closest: | |
401 | if(distance1 < distance2) | |
402 | { | |
403 | closest_x = dist_x1 + vertex->GetX(); | |
404 | closest_y = dist_y1 + vertex->GetY(); | |
405 | } | |
406 | else | |
407 | { | |
408 | closest_x = dist_x2 + vertex->GetX(); | |
409 | closest_y = dist_y2 + vertex->GetY(); | |
410 | } | |
411 | ||
412 | //Get the z coordinate: | |
413 | Double_t angle1 = atan2((closest_y-GetCenterY()),(closest_x-GetCenterX())); | |
9ca67380 | 414 | if(angle1 < 0) angle1 = angle1 + 2*AliL3Transform::Pi(); |
6d4f1901 | 415 | |
416 | Double_t angle2 = atan2((GetFirstPointY()-GetCenterY()),(GetFirstPointX()-GetCenterX())); | |
9ca67380 | 417 | if(angle2 < 0) angle2 = angle2 + 2*AliL3Transform::Pi(); |
6d4f1901 | 418 | |
419 | Double_t diff_angle = angle1 - angle2; | |
9ca67380 | 420 | diff_angle = fmod(diff_angle,2*AliL3Transform::Pi()); |
6d4f1901 | 421 | |
9ca67380 | 422 | if((GetCharge()*diff_angle) < 0) diff_angle = diff_angle + GetCharge()*2*AliL3Transform::Pi(); |
6d4f1901 | 423 | Double_t s_tot = fabs(diff_angle)*GetRadius(); |
424 | ||
425 | closest_z = GetFirstPointZ() - s_tot*GetTgl(); | |
426 | } |