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108615fc | 1 | //Author: Anders Strand Vestbo |
2 | //Author: Uli Frankenfeld | |
3 | //Last Modified: 06.03.2001 | |
4 | ||
5 | //____________________________________ | |
6 | // AliL3Track | |
7 | // | |
8 | // Base track class for L3 | |
9 | ||
10 | //Changes: | |
11 | ||
12 | //14.03.01: Moved fHitNumbers from protected to private.-ASV | |
13 | // Set memory to zero in ctor. | |
14 | // Moved fNHits 2 private. Protected data members not a good idea after all. | |
15 | //19.03.01: Made the method void Set(AliL3Track) virtual. | |
16 | ||
17 | #include "AliL3RootTypes.h" | |
18 | ||
0391971c | 19 | #include "AliL3Defs.h" |
108615fc | 20 | #include "AliL3Logging.h" |
21 | #include "AliL3Track.h" | |
0391971c | 22 | #include "AliL3Transform.h" |
108615fc | 23 | #include <math.h> |
24 | ||
0391971c | 25 | |
108615fc | 26 | ClassImp(AliL3Track) |
27 | ||
28 | Float_t AliL3Track::BFACT = 0.0029980; | |
29 | Float_t AliL3Track::bField = 0.2; | |
30 | Double_t AliL3Track::pi=3.14159265358979323846; | |
31 | ||
32 | AliL3Track::AliL3Track() | |
33 | { | |
34 | //Constructor | |
35 | ||
36 | fNHits = 0; | |
37 | fMCid = -1; | |
38 | fKappa=0; | |
39 | fRadius=0; | |
40 | fCenterX=0; | |
41 | fCenterY=0; | |
42 | ComesFromMainVertex(false); | |
43 | fQ = 0; | |
44 | fPhi0=0; | |
45 | fPsi=0; | |
46 | fR0=0; | |
47 | fTanl=0; | |
48 | fZ0=0; | |
49 | fPt=0; | |
50 | fLength=0; | |
51 | fIsLocal=true; | |
52 | fRowRange[0]=0; | |
53 | fRowRange[1]=0; | |
54 | memset(fHitNumbers,0,174*sizeof(UInt_t)); | |
55 | } | |
56 | ||
57 | void AliL3Track::Set(AliL3Track *tpt){ | |
58 | ||
3a735e00 | 59 | SetRowRange(tpt->GetFirstRow(),tpt->GetLastRow()); |
60 | SetPhi0(tpt->GetPhi0()); | |
61 | SetKappa(tpt->GetKappa()); | |
62 | SetNHits(tpt->GetNHits()); | |
63 | SetFirstPoint(tpt->GetFirstPointX(),tpt->GetFirstPointY(),tpt->GetFirstPointZ()); | |
64 | SetLastPoint(tpt->GetLastPointX(),tpt->GetLastPointY(),tpt->GetLastPointZ()); | |
65 | SetPt(tpt->GetPt()); | |
66 | SetPsi(tpt->GetPsi()); | |
67 | SetTgl(tpt->GetTgl()); | |
68 | SetCharge(tpt->GetCharge()); | |
69 | SetHits(tpt->GetNHits(),(UInt_t *)tpt->GetHitNumbers()); | |
108615fc | 70 | |
108615fc | 71 | } |
72 | ||
73 | ||
74 | AliL3Track::~AliL3Track() | |
75 | { | |
76 | ||
77 | } | |
78 | ||
79 | Double_t AliL3Track::GetP() const | |
80 | { | |
81 | // Returns total momentum. | |
82 | ||
83 | return fabs(GetPt())*sqrt(1. + GetTgl()*GetTgl()); | |
84 | ||
85 | } | |
86 | ||
87 | Double_t AliL3Track::GetPseudoRapidity() const | |
88 | { | |
89 | return 0.5 * log((GetP() + GetPz()) / (GetP() - GetPz())); | |
90 | } | |
91 | ||
92 | Double_t AliL3Track::GetEta() const | |
93 | { | |
94 | return GetPseudoRapidity(); | |
95 | } | |
96 | ||
97 | Double_t AliL3Track::GetRapidity() const | |
98 | { | |
99 | Double_t m_pi = 0.13957; | |
100 | return 0.5 * log((m_pi + GetPz()) / (m_pi - GetPz())); | |
101 | } | |
102 | ||
0391971c | 103 | void AliL3Track::Rotate(Int_t slice) |
104 | { | |
105 | ||
106 | //Rotate track to global parameters | |
107 | ||
108 | AliL3Transform *transform = new AliL3Transform(); | |
109 | ||
110 | Float_t psi[1] = {GetPsi()}; | |
111 | transform->Local2GlobalAngle(psi,slice); | |
112 | SetPsi(psi[0]); | |
113 | Float_t first[3]; | |
114 | first[0] = GetFirstPointX(); | |
115 | first[1] = GetFirstPointY(); | |
116 | first[2] = GetFirstPointZ(); | |
117 | transform->Local2Global(first,slice); | |
118 | SetFirstPoint(first[0],first[1],first[2]); | |
119 | Float_t last[3]; | |
120 | last[0] = GetLastPointX(); | |
121 | last[1] = GetLastPointY(); | |
122 | last[2] = GetLastPointZ(); | |
123 | transform->Local2Global(last,slice); | |
124 | SetLastPoint(last[0],last[1],last[2]); | |
125 | ||
126 | fIsLocal=false; | |
127 | delete transform; | |
128 | } | |
129 | ||
108615fc | 130 | void AliL3Track::CalculateHelix(){ |
131 | //Calculate Radius, CenterX and Centery from Psi, X0, Y0 | |
132 | // | |
133 | ||
134 | fRadius = fPt / (BFACT*bField); | |
135 | if(fRadius) fKappa = 1./fRadius; | |
136 | else fRadius = 999999; //just zero | |
137 | Double_t trackPhi0 = fPsi + fQ *0.5 * pi; | |
138 | ||
139 | fCenterX = fFirstPoint[0] - fRadius * cos(trackPhi0); | |
140 | fCenterY = fFirstPoint[1] - fRadius * sin(trackPhi0); | |
141 | } | |
142 | ||
0391971c | 143 | Double_t AliL3Track::GetCrossingAngle(Int_t padrow) |
144 | { | |
145 | //Calculate the crossing angle between track and given padrow. | |
146 | ||
147 | if(!IsLocal()) | |
148 | { | |
149 | printf("Track is not given in local coordinates\n"); | |
150 | return 0; | |
151 | } | |
152 | ||
153 | Float_t xyz[3]; | |
154 | if(!GetCrossingPoint(padrow,xyz)) | |
155 | printf("AliL3HoughTrack::GetCrossingPoint : Track does not cross line!!\n"); | |
156 | ||
157 | //Take the dot product of the tangent vector of the track, and | |
158 | //vector perpendicular to the padrow. | |
159 | ||
160 | Double_t tangent[2]; | |
161 | tangent[1] = (xyz[0] - GetCenterX())/GetRadius(); | |
162 | tangent[0] = -1.*(xyz[1] - GetCenterY())/GetRadius(); | |
163 | ||
164 | Double_t perp_padrow[2] = {1,0}; //locally in slice | |
165 | ||
166 | Double_t cos_beta = fabs(tangent[0]*perp_padrow[0] + tangent[1]*perp_padrow[1]); | |
167 | return acos(cos_beta); | |
168 | ||
169 | } | |
170 | ||
171 | Bool_t AliL3Track::GetCrossingPoint(Int_t padrow,Float_t *xyz) | |
172 | { | |
173 | //Assumes the track is given in local coordinates | |
174 | ||
175 | AliL3Transform *transform = new AliL3Transform(); | |
176 | if(!IsLocal()) | |
177 | { | |
178 | printf("GetCrossingPoint: Track is given on global coordinates\n"); | |
179 | return false; | |
180 | } | |
181 | ||
182 | Double_t xHit = transform->Row2X(padrow); | |
183 | ||
184 | xyz[0] = xHit; | |
185 | Double_t aa = (xHit - GetCenterX())*(xHit - GetCenterX()); | |
186 | Double_t r2 = GetRadius()*GetRadius(); | |
187 | if(aa > r2) | |
188 | return false; | |
189 | ||
190 | Double_t aa2 = sqrt(r2 - aa); | |
191 | Double_t y1 = GetCenterY() + aa2; | |
192 | Double_t y2 = GetCenterY() - aa2; | |
193 | xyz[1] = y1; | |
194 | if(fabs(y2) < fabs(y1)) xyz[1] = y2; | |
195 | ||
196 | Double_t yHit = xyz[1]; | |
197 | Double_t angle1 = atan2((yHit - GetCenterY()),(xHit - GetCenterX())); | |
198 | if(angle1 < 0) angle1 += 2.*Pi; | |
199 | Double_t angle2 = atan2((GetFirstPointY() - GetCenterY()),(GetFirstPointX() - GetCenterX())); | |
200 | if(angle2 < 0) angle2 += 2.*Pi; | |
201 | Double_t diff_angle = angle1 - angle2; | |
202 | diff_angle = fmod(diff_angle,2*Pi); | |
203 | if((GetCharge()*diff_angle) > 0) diff_angle = diff_angle - GetCharge()*2.*Pi; | |
204 | Double_t s_tot = fabs(diff_angle)*GetRadius(); | |
205 | Double_t zHit = GetFirstPointZ() + s_tot*GetTgl(); | |
206 | xyz[2] = zHit; | |
207 | ||
208 | delete transform; | |
209 | return true; | |
210 | } | |
211 | ||
212 | ||
108615fc | 213 | Bool_t AliL3Track::CalculateReferencePoint(Double_t angle){ |
214 | // Global coordinate: crossing point with y = ax+ b; a=tan(angle-Pi/2); | |
215 | // | |
216 | const Double_t rr=132; //position of referece plane | |
217 | const Double_t xr = cos(angle) *rr; | |
218 | const Double_t yr = sin(angle) *rr; | |
219 | ||
220 | Double_t a = tan(angle-pi/2); | |
221 | Double_t b = yr - a * xr; | |
222 | ||
223 | Double_t pp=(fCenterX+a*fCenterY-a*b)/(1+pow(a,2)); | |
224 | Double_t qq=(pow(fCenterX,2)+pow(fCenterY,2)-2*fCenterY*b+pow(b,2)-pow(fRadius,2))/(1+pow(a,2)); | |
225 | ||
226 | Double_t racine = pp*pp-qq; | |
227 | if(racine<0) return IsPoint(kFALSE); //no Point | |
228 | ||
229 | Double_t rootRacine = sqrt(racine); | |
230 | Double_t x0 = pp+rootRacine; | |
231 | Double_t x1 = pp-rootRacine; | |
232 | Double_t y0 = a*x0 + b; | |
233 | Double_t y1 = a*x1 + b; | |
234 | ||
235 | Double_t diff0 = sqrt(pow(x0-xr,2)+pow(y0-yr,2)); | |
236 | Double_t diff1 = sqrt(pow(x1-xr,2)+pow(y1-yr,2)); | |
237 | ||
238 | if(diff0<diff1){ | |
239 | fPoint[0]=x0; | |
240 | fPoint[1]=y0; | |
241 | } | |
242 | else{ | |
243 | fPoint[0]=x1; | |
244 | fPoint[1]=y1; | |
245 | } | |
246 | ||
247 | Double_t pointPhi0 = atan2(fPoint[1]-fCenterY,fPoint[0]-fCenterX); | |
248 | Double_t trackPhi0 = atan2(fFirstPoint[1]-fCenterY,fFirstPoint[0]-fCenterX); | |
249 | if(fabs(trackPhi0-pointPhi0)>pi){ | |
250 | if(trackPhi0<pointPhi0) trackPhi0 += 2*pi; | |
251 | else pointPhi0 += 2*pi; | |
252 | } | |
253 | Double_t stot = -fQ * (pointPhi0-trackPhi0) * fRadius ; | |
254 | fPoint[2] = fFirstPoint[2] + stot * fTanl; | |
255 | ||
256 | fPointPsi = pointPhi0 - fQ * 0.5 * pi; | |
257 | if(fPointPsi<0.) fPointPsi+= 2*pi; | |
258 | fPointPsi = fmod(fPointPsi, 2*pi); | |
259 | ||
260 | return IsPoint(kTRUE); | |
261 | } | |
262 | ||
263 | Bool_t AliL3Track::CalculateEdgePoint(Double_t angle){ | |
264 | // Global coordinate: crossing point with y = ax; a=tan(angle); | |
265 | // | |
266 | Double_t rmin=80; //min Radius of TPC | |
267 | Double_t rmax=260; //max Radius of TPC | |
268 | ||
269 | Double_t a = tan(angle); | |
270 | Double_t pp=(fCenterX+a*fCenterY)/(1+pow(a,2)); | |
271 | Double_t qq=(pow(fCenterX,2)+pow(fCenterY,2)-pow(fRadius,2))/(1+pow(a,2)); | |
272 | Double_t racine = pp*pp-qq; | |
273 | if(racine<0) return IsPoint(kFALSE); //no Point | |
274 | Double_t rootRacine = sqrt(racine); | |
275 | Double_t x0 = pp+rootRacine; | |
276 | Double_t x1 = pp-rootRacine; | |
277 | Double_t y0 = a*x0; | |
278 | Double_t y1 = a*x1; | |
279 | ||
280 | Double_t r0 = sqrt(pow(x0,2)+pow(y0,2)); | |
281 | Double_t r1 = sqrt(pow(x1,2)+pow(y1,2)); | |
282 | //find the right crossing point: | |
283 | //inside the TPC modules | |
284 | Bool_t ok0 = kFALSE; | |
285 | Bool_t ok1 = kFALSE; | |
472d9e24 | 286 | |
108615fc | 287 | if(r0>rmin&&r0<rmax){ |
288 | Double_t da=atan2(y0,x0); | |
472d9e24 | 289 | if(da<0) da+=2*pi; |
108615fc | 290 | if(fabs(da-angle)<0.5) |
291 | ok0 = kTRUE; | |
292 | } | |
293 | if(r1>rmin&&r1<rmax){ | |
472d9e24 | 294 | Double_t da=atan2(y1,x1); |
295 | if(da<0) da+=2*pi; | |
108615fc | 296 | if(fabs(da-angle)<0.5) |
297 | ok1 = kTRUE; | |
298 | } | |
299 | if(!(ok0||ok1)) return IsPoint(kFALSE); //no Point | |
300 | ||
301 | if(ok0&&ok1){ | |
302 | Double_t diff0 = sqrt(pow(fFirstPoint[0]-x0,2)+pow(fFirstPoint[1]-y0,2)); | |
303 | Double_t diff1 = sqrt(pow(fFirstPoint[0]-x1,2)+pow(fFirstPoint[1]-y1,2)); | |
304 | if(diff0<diff1) ok1 = kFALSE; //use ok0 | |
305 | else ok0 = kFALSE; //use ok1 | |
306 | } | |
307 | if(ok0){fPoint[0]=x0; fPoint[1]=y0;} | |
308 | else {fPoint[0]=x1; fPoint[1]=y1;} | |
309 | ||
310 | Double_t pointPhi0 = atan2(fPoint[1]-fCenterY,fPoint[0]-fCenterX); | |
311 | Double_t trackPhi0 = atan2(fFirstPoint[1]-fCenterY,fFirstPoint[0]-fCenterX); | |
312 | if(fabs(trackPhi0-pointPhi0)>pi){ | |
313 | if(trackPhi0<pointPhi0) trackPhi0 += 2*pi; | |
314 | else pointPhi0 += 2*pi; | |
315 | } | |
316 | Double_t stot = -fQ * (pointPhi0-trackPhi0) * fRadius ; | |
317 | fPoint[2] = fFirstPoint[2] + stot * fTanl; | |
318 | ||
319 | fPointPsi = pointPhi0 - fQ * 0.5 * pi; | |
320 | if(fPointPsi<0.) fPointPsi+= 2*pi; | |
321 | fPointPsi = fmod(fPointPsi, 2*pi); | |
322 | ||
323 | return IsPoint(kTRUE); | |
324 | } | |
325 | ||
326 | Bool_t AliL3Track::CalculatePoint(Double_t xplane){ | |
327 | // Local coordinate: crossing point with x plane | |
328 | // | |
329 | Double_t racine = pow(fRadius,2)-pow(xplane-fCenterX,2); | |
330 | if(racine<0) return IsPoint(kFALSE); | |
331 | Double_t rootRacine = sqrt(racine); | |
332 | ||
333 | Double_t y0 = fCenterY + rootRacine; | |
334 | Double_t y1 = fCenterY - rootRacine; | |
335 | //Double_t diff0 = sqrt(pow(fFirstPoint[0]-xplane)+pow(fFirstPoint[1]-y0)); | |
336 | //Double_t diff1 = sqrt(pow(fFirstPoint[0]-xplane)+pow(fFirstPoint[1]-y1)); | |
337 | Double_t diff0 = fabs(y0-fFirstPoint[1]); | |
338 | Double_t diff1 = fabs(y1-fFirstPoint[1]); | |
339 | ||
340 | fPoint[0]=xplane; | |
341 | if(diff0<diff1) fPoint[1]=y0; | |
342 | else fPoint[1]=y1; | |
343 | ||
344 | Double_t pointPhi0 = atan2(fPoint[1]-fCenterY,fPoint[0]-fCenterX); | |
345 | Double_t trackPhi0 = atan2(fFirstPoint[1]-fCenterY,fFirstPoint[0]-fCenterX); | |
346 | if(fabs(trackPhi0-pointPhi0)>pi){ | |
347 | if(trackPhi0<pointPhi0) trackPhi0 += 2*pi; | |
348 | else pointPhi0 += 2*pi; | |
349 | } | |
350 | Double_t stot = -fQ * (pointPhi0-trackPhi0) * fRadius ; | |
351 | fPoint[2] = fFirstPoint[2] + stot * fTanl; | |
352 | ||
353 | fPointPsi = pointPhi0 - fQ * 0.5 * pi; | |
354 | if(fPointPsi<0.) fPointPsi+= 2*pi; | |
355 | fPointPsi = fmod(fPointPsi, 2*pi); | |
356 | ||
357 | return IsPoint(kTRUE); | |
358 | } | |
359 |