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88cb7938 | 1 | /************************************************************************** |
3decf5cb | 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 | ||
b2a60966 | 16 | /* $Id$ */ |
17 | ||
3decf5cb | 18 | //_________________________________________________________________________ |
b2a60966 | 19 | // Implementation of the PHOS manager class for fast simulations |
20 | // Tracks particles until the reach a grossly designed PHOS module | |
21 | // Modify the particles property (momentum, energy, type) according to | |
22 | // the PHOS response function. The result is called a virtual reconstructed | |
23 | // particle. | |
24 | // | |
25 | //*-- Author: Yves Schutz (SUBATECH) | |
3decf5cb | 26 | |
27 | // --- ROOT system --- | |
3a4295ee | 28 | |
88cb7938 | 29 | #include <TBRIK.h> |
88cb7938 | 30 | #include <TGeometry.h> |
31 | #include <TNode.h> | |
32 | #include <TParticle.h> | |
e957fea8 | 33 | #include "TClonesArray.h" |
88cb7938 | 34 | #include <TVirtualMC.h> |
3decf5cb | 35 | |
36 | // --- Standard library --- | |
37 | ||
3decf5cb | 38 | // --- AliRoot header files --- |
3a4295ee | 39 | #include "AliPHOSFastRecParticle.h" |
88cb7938 | 40 | #include "AliPHOSGeometry.h" |
41 | #include "AliPHOSLoader.h" | |
3decf5cb | 42 | #include "AliPHOSvFast.h" |
3decf5cb | 43 | #include "AliRun.h" |
3decf5cb | 44 | |
45 | ClassImp(AliPHOSvFast) | |
46 | ||
47 | //____________________________________________________________________________ | |
3a4295ee | 48 | AliPHOSvFast::AliPHOSvFast() : AliPHOS() |
3decf5cb | 49 | { |
3a4295ee | 50 | // default ctor : initialize data member |
51 | fBigBoxX = 0. ; | |
52 | fBigBoxY = 0. ; | |
53 | fBigBoxZ = 0. ; | |
54 | fFastRecParticles = 0 ; | |
55 | fNRecParticles = 0 ; | |
56 | fRan = 0 ; | |
57 | fResPara1 = 0. ; | |
58 | fResPara2 = 0. ; | |
59 | fResPara3 = 0. ; | |
60 | fPosParaA0 = 0. ; | |
61 | fPosParaA1 = 0. ; | |
62 | fPosParaB0 = 0. ; | |
63 | fPosParaB1 = 0. ; | |
64 | fPosParaB2 = 0. ; | |
b2a60966 | 65 | |
3decf5cb | 66 | } |
67 | ||
68 | //____________________________________________________________________________ | |
69 | AliPHOSvFast::AliPHOSvFast(const char *name, const char *title): | |
70 | AliPHOS(name,title) | |
71 | { | |
b2a60966 | 72 | // ctor |
73 | ||
3decf5cb | 74 | |
88cb7938 | 75 | // create the Loader |
7a9d98f9 | 76 | |
77 | SetBigBox(0, GetGeometry()->GetOuterBoxSize(0) ) ; | |
78 | SetBigBox(1, GetGeometry()->GetOuterBoxSize(3) + GetGeometry()->GetCPVBoxSize(1) ) ; | |
79 | SetBigBox(2, GetGeometry()->GetOuterBoxSize(2) ); | |
80 | ||
81 | fNRecParticles = 0 ; | |
82 | fFastRecParticles = new AliPHOSFastRecParticle::FastRecParticlesList("AliPHOSFastRecParticle", 100) ; | |
83 | ||
84 | fResPara1 = 0.030 ; // GeV | |
85 | fResPara2 = 0.00003 ; | |
86 | fResPara3 = 0.00001 ; | |
87 | ||
88 | fPosParaA0 = 2.87 ; // mm | |
89 | fPosParaA1 = -0.0975 ; | |
90 | fPosParaB0 = 0.257 ; | |
91 | fPosParaB1 = 0.137 ; | |
92 | fPosParaB2 = 0.00619 ; | |
3decf5cb | 93 | } |
94 | ||
95 | //____________________________________________________________________________ | |
96 | AliPHOSvFast::~AliPHOSvFast() | |
97 | { | |
b2a60966 | 98 | // dtor |
3decf5cb | 99 | |
a73f33f0 | 100 | fFastRecParticles->Delete() ; |
101 | delete fFastRecParticles ; | |
102 | fFastRecParticles = 0 ; | |
3decf5cb | 103 | |
104 | } | |
105 | ||
780fda6d | 106 | //____________________________________________________________________________ |
107 | void AliPHOSvFast::Copy(AliPHOSvFast & fast) | |
108 | { | |
109 | TObject::Copy(fast) ; | |
110 | AliPHOS::Copy(fast) ; | |
111 | fast.fBigBoxX = fBigBoxX ; | |
112 | fast.fBigBoxY = fBigBoxY ; | |
113 | fast.fBigBoxZ = fBigBoxZ ; | |
114 | fast.fNRecParticles = fNRecParticles ; | |
115 | fast.fRan = fRan ; | |
116 | fast.fResPara1 = fResPara1 ; | |
117 | fast.fResPara2 = fResPara2 ; | |
118 | fast.fResPara3 = fResPara3 ; | |
119 | fast.fPosParaA0 = fPosParaA0 ; | |
120 | fast.fPosParaA1 = fPosParaA1 ; | |
121 | fast.fPosParaB0 = fPosParaB0 ; | |
122 | fast.fPosParaB1 = fPosParaB1 ; | |
123 | fast.fFastRecParticles = new TClonesArray(fFastRecParticles->GetClass()->GetName(), 100) ; | |
124 | Int_t index ; | |
125 | for (index = 0 ; index < fFastRecParticles->GetEntries(); index++) | |
126 | (fast.fFastRecParticles)->AddAt(fFastRecParticles->At(index), index) ; | |
127 | } | |
128 | ||
3decf5cb | 129 | //____________________________________________________________________________ |
a73f33f0 | 130 | void AliPHOSvFast::AddRecParticle(const AliPHOSFastRecParticle & rp) |
131 | { | |
b2a60966 | 132 | // Add a virtually reconstructed particle to the list |
133 | ||
f96d3dc7 | 134 | new( (*fFastRecParticles)[fNRecParticles] ) AliPHOSFastRecParticle(rp) ; |
135 | fNRecParticles++ ; | |
3decf5cb | 136 | } |
137 | ||
138 | //____________________________________________________________________________ | |
139 | void AliPHOSvFast::BuildGeometry() | |
140 | { | |
3decf5cb | 141 | // Build the PHOS geometry for the ROOT display |
b2a60966 | 142 | //BEGIN_HTML |
143 | /* | |
144 | <H2> | |
145 | PHOS FAST in ALICE displayed by root | |
146 | </H2> | |
147 | <H4> All Views </H4> | |
148 | <P> | |
149 | <CENTER> | |
150 | <IMG Align=BOTTOM ALT="Fast All Views" SRC="../images/AliPHOSvFastAllViews.gif"> | |
151 | </CENTER></P> | |
152 | <H4> Front View </H4> | |
153 | <P> | |
154 | <CENTER> | |
155 | <IMG Align=BOTTOM ALT="Fast Front View" SRC="../images/AliPHOSvFastFrontView.gif"> | |
156 | </CENTER></P> | |
157 | */ | |
158 | //END_HTML | |
159 | ||
3decf5cb | 160 | const Int_t kColorPHOS = kRed ; |
161 | ||
a8c47ab6 | 162 | Double_t const kRADDEG = 180.0 / TMath::Pi() ; |
3decf5cb | 163 | |
164 | new TBRIK( "BigBox", "PHOS box", "void", GetBigBox(0)/2, | |
165 | GetBigBox(1)/2, | |
166 | GetBigBox(2)/2 ); | |
167 | ||
168 | // position PHOS into ALICE | |
169 | ||
fa7cce36 | 170 | Float_t r = GetGeometry()->GetIPtoCrystalSurface() + GetBigBox(1) / 2.0 ; |
3decf5cb | 171 | Int_t number = 988 ; |
fa7cce36 | 172 | Float_t pphi = TMath::ATan( GetBigBox(0) / ( 2.0 * GetGeometry()->GetIPtoCrystalSurface() ) ) ; |
3decf5cb | 173 | pphi *= kRADDEG ; |
174 | TNode * top = gAlice->GetGeometry()->GetNode("alice") ; | |
175 | ||
176 | char * nodename = new char[20] ; | |
177 | char * rotname = new char[20] ; | |
178 | ||
fa7cce36 | 179 | for( Int_t i = 1; i <= GetGeometry()->GetNModules(); i++ ) { |
180 | Float_t angle = pphi * 2 * ( i - GetGeometry()->GetNModules() / 2.0 - 0.5 ) ; | |
3decf5cb | 181 | sprintf(rotname, "%s%d", "rot", number++) ; |
182 | new TRotMatrix(rotname, rotname, 90, angle, 90, 90 + angle, 0, 0); | |
183 | top->cd(); | |
184 | sprintf(nodename,"%s%d", "Module", i) ; | |
185 | Float_t x = r * TMath::Sin( angle / kRADDEG ) ; | |
186 | Float_t y = -r * TMath::Cos( angle / kRADDEG ) ; | |
187 | TNode * bigboxnode = new TNode(nodename, nodename, "BigBox", x, y, 0, rotname ) ; | |
188 | bigboxnode->SetLineColor(kColorPHOS) ; | |
189 | fNodes->Add(bigboxnode) ; | |
190 | } | |
191 | delete[] nodename ; | |
192 | delete[] rotname ; | |
193 | } | |
194 | ||
195 | //____________________________________________________________________________ | |
196 | void AliPHOSvFast::CreateGeometry() | |
197 | { | |
b2a60966 | 198 | // Create the geometry for GEANT |
199 | ||
3decf5cb | 200 | AliPHOSvFast *phostmp = (AliPHOSvFast*)gAlice->GetModule("PHOS") ; |
b2a60966 | 201 | |
3decf5cb | 202 | if ( phostmp == NULL ) { |
203 | ||
204 | fprintf(stderr, "PHOS detector not found!\n") ; | |
205 | return ; | |
206 | ||
207 | } | |
208 | ||
209 | // Get pointer to the array containing media indeces | |
210 | Int_t *idtmed = fIdtmed->GetArray() - 699 ; | |
211 | ||
212 | Float_t bigbox[3] ; | |
213 | bigbox[0] = GetBigBox(0) / 2.0 ; | |
214 | bigbox[1] = GetBigBox(1) / 2.0 ; | |
215 | bigbox[2] = GetBigBox(2) / 2.0 ; | |
216 | ||
217 | gMC->Gsvolu("PHOS", "BOX ", idtmed[798], bigbox, 3) ; | |
218 | ||
219 | // --- Position PHOS mdules in ALICE setup --- | |
220 | ||
221 | Int_t idrotm[99] ; | |
a8c47ab6 | 222 | Double_t const kRADDEG = 180.0 / TMath::Pi() ; |
3decf5cb | 223 | |
fa7cce36 | 224 | for( Int_t i = 1; i <= GetGeometry()->GetNModules(); i++ ) { |
3decf5cb | 225 | |
fa7cce36 | 226 | Float_t angle = GetGeometry()->GetPHOSAngle(i) ; |
3decf5cb | 227 | AliMatrix(idrotm[i-1], 90.0, angle, 90.0, 90.0+angle, 0.0, 0.0) ; |
228 | ||
fa7cce36 | 229 | Float_t r = GetGeometry()->GetIPtoCrystalSurface() + GetBigBox(1) / 2.0 ; |
3decf5cb | 230 | |
231 | Float_t xP1 = r * TMath::Sin( angle / kRADDEG ) ; | |
232 | Float_t yP1 = -r * TMath::Cos( angle / kRADDEG ) ; | |
3decf5cb | 233 | gMC->Gspos("PHOS", i, "ALIC", xP1, yP1, 0.0, idrotm[i-1], "ONLY") ; |
234 | ||
235 | } // for GetNModules | |
236 | ||
237 | } | |
238 | ||
239 | ||
240 | //____________________________________________________________________________ | |
241 | void AliPHOSvFast::Init(void) | |
242 | { | |
b2a60966 | 243 | // Prints out an information message |
244 | ||
3decf5cb | 245 | Int_t i; |
246 | ||
247 | printf("\n"); | |
248 | for(i=0;i<35;i++) printf("*"); | |
249 | printf(" FAST PHOS_INIT "); | |
250 | for(i=0;i<35;i++) printf("*"); | |
251 | printf("\n"); | |
252 | ||
253 | // Here the PHOS initialisation code (if any!) | |
254 | ||
255 | for(i=0;i<80;i++) printf("*"); | |
256 | printf("\n"); | |
257 | ||
258 | } | |
259 | ||
260 | //___________________________________________________________________________ | |
3a4295ee | 261 | Float_t AliPHOSvFast::GetBigBox(Int_t index) const |
3decf5cb | 262 | { |
b2a60966 | 263 | // Get the X, Y or Z dimension of the box describing a PHOS module |
264 | ||
3decf5cb | 265 | Float_t rv = 0 ; |
266 | ||
267 | switch (index) { | |
268 | case 0: | |
269 | rv = fBigBoxX ; | |
270 | break ; | |
271 | case 1: | |
272 | rv = fBigBoxY ; | |
273 | break ; | |
274 | case 2: | |
275 | rv = fBigBoxZ ; | |
276 | break ; | |
277 | } | |
278 | return rv ; | |
279 | } | |
3decf5cb | 280 | //___________________________________________________________________________ |
88cb7938 | 281 | |
282 | void AliPHOSvFast::MakeBranch(Option_t* opt) | |
3decf5cb | 283 | { |
b2a60966 | 284 | // Create new branch in the current reconstructed Root Tree |
88cb7938 | 285 | AliDetector::MakeBranch(opt); |
3a4295ee | 286 | const char *cd = strstr(opt,"R"); |
3decf5cb | 287 | |
88cb7938 | 288 | if (fFastRecParticles && fLoader->TreeR() && cd) { |
289 | MakeBranchInTree(fLoader->TreeR(), GetName(), &fFastRecParticles, fBufferSize, 0); | |
3decf5cb | 290 | } |
291 | } | |
a73f33f0 | 292 | //____________________________________________________________________________ |
88cb7938 | 293 | |
fc7e2f43 | 294 | Double_t AliPHOSvFast::MakeEnergy(Double_t energy) |
a73f33f0 | 295 | { |
b2a60966 | 296 | // Smears the energy according to the energy dependent energy resolution. |
297 | // A gaussian distribution is assumed | |
298 | ||
b1aa729d | 299 | Double_t sigma = SigmaE(energy) ; |
300 | return fRan.Gaus(energy, sigma) ; | |
a73f33f0 | 301 | } |
a73f33f0 | 302 | //____________________________________________________________________________ |
88cb7938 | 303 | |
fc7e2f43 | 304 | TVector3 AliPHOSvFast::MakePosition(Double_t energy, TVector3 pos, Double_t theta, Double_t phi) |
a73f33f0 | 305 | { |
b2a60966 | 306 | // Smears the impact position according to the energy dependent position resolution |
307 | // A gaussian position distribution is assumed | |
308 | ||
b1aa729d | 309 | TVector3 newpos ; |
310 | Double_t sigma = SigmaP( energy, theta*180./TMath::Pi() ) ; | |
311 | Double_t x = fRan.Gaus( pos.X(), sigma ) ; | |
312 | sigma = SigmaP( energy, phi*180./TMath::Pi() ) ; | |
313 | Double_t z = fRan.Gaus( pos.Z(), sigma ) ; | |
314 | Double_t y = pos.Y() ; | |
315 | ||
316 | newpos.SetX(x) ; | |
317 | newpos.SetY(y) ; | |
318 | newpos.SetZ(z) ; | |
319 | ||
320 | return newpos ; | |
321 | } | |
a73f33f0 | 322 | |
b1aa729d | 323 | //____________________________________________________________________________ |
fc7e2f43 | 324 | void AliPHOSvFast::MakeRecParticle(Int_t modid, TVector3 pos, AliPHOSFastRecParticle & rp) |
b1aa729d | 325 | { |
b2a60966 | 326 | // Modify the primary particle properties according |
327 | // 1. the response function of PHOS | |
328 | // 2. the performance of the EMC+PPSD setup | |
329 | ||
b1aa729d | 330 | Int_t type = MakeType( rp ) ; |
a73f33f0 | 331 | rp.SetType(type) ; |
332 | ||
333 | ||
334 | // get the detected energy | |
335 | ||
336 | TLorentzVector momentum ; | |
337 | rp.Momentum(momentum) ; | |
338 | Double_t kineticenergy = TMath::Sqrt( TMath::Power(momentum.E(), 2) - TMath::Power(rp.GetMass(), 2) ) ; | |
339 | Double_t modifiedkineticenergy = MakeEnergy(kineticenergy ) ; | |
b1aa729d | 340 | Double_t modifiedenergy = TMath::Sqrt( TMath::Power(modifiedkineticenergy, 2) |
341 | + TMath::Power( rp.GetMass(), 2) ) ; | |
342 | ||
343 | // get the angle of incidence | |
344 | ||
345 | Double_t incidencetheta = 90. * TMath::Pi() /180 - rp.Theta() ; | |
fa7cce36 | 346 | Double_t incidencephi = ( 270 + GetGeometry()->GetPHOSAngle(modid) ) * TMath::Pi() / 180. - rp.Phi() ; |
b1aa729d | 347 | |
348 | // get the detected direction | |
349 | ||
350 | TVector3 modifiedposition = MakePosition(kineticenergy, pos, incidencetheta, incidencephi) ; | |
351 | modifiedposition *= modifiedkineticenergy / modifiedposition.Mag() ; | |
352 | ||
353 | // Set the modified 4-momentum of the reconstructed particle | |
354 | ||
355 | rp.SetMomentum(modifiedposition.X(), modifiedposition.Y(), modifiedposition.Z(), modifiedenergy) ; | |
356 | ||
a73f33f0 | 357 | } |
358 | ||
359 | //____________________________________________________________________________ | |
b1aa729d | 360 | Int_t AliPHOSvFast::MakeType(AliPHOSFastRecParticle & rp ) |
a73f33f0 | 361 | { |
b2a60966 | 362 | // Generate a particle type using the performance of the EMC+PPSD setup |
363 | ||
9ec91567 | 364 | Int_t rv = AliPHOSFastRecParticle::kUNDEFINED ; |
b1aa729d | 365 | Int_t charge = (Int_t)rp.GetPDG()->Charge() ; |
366 | Int_t test ; | |
367 | Float_t ran ; | |
f96d3dc7 | 368 | if ( charge != 0 && ( TMath::Abs(rp.GetPdgCode()) != 11 ) ) |
b1aa729d | 369 | test = - 1 ; |
370 | else | |
371 | test = rp.GetPdgCode() ; | |
372 | ||
a4765fe4 | 373 | Fatal("MakeType", "SHOULD NOT BE USED until values of probabilities are properly set ") ; |
374 | // NB: ALL VALUES SHOULD BE CHECKED !!!! | |
b1aa729d | 375 | switch (test) { |
376 | ||
3a4295ee | 377 | case 22: // it's a photon // NB: ALL VALUES SHOLD BE CHECKED !!!! |
b1aa729d | 378 | ran = fRan.Rndm() ; |
3a4295ee | 379 | if( ran <= 0.9498 ) |
380 | rv = AliPHOSFastRecParticle::kNEUTRALHAFAST ; | |
381 | else | |
382 | rv = AliPHOSFastRecParticle::kNEUTRALEMFAST ; | |
b1aa729d | 383 | break ; |
384 | ||
385 | case 2112: // it's a neutron | |
386 | ran = fRan.Rndm() ; | |
387 | if ( ran <= 0.9998 ) | |
3a4295ee | 388 | rv = AliPHOSFastRecParticle::kNEUTRALHASLOW ; |
b1aa729d | 389 | else |
3a4295ee | 390 | rv = AliPHOSFastRecParticle::kNEUTRALEMSLOW ; |
b1aa729d | 391 | break ; |
3a4295ee | 392 | |
b1aa729d | 393 | case -2112: // it's a anti-neutron |
394 | ran = fRan.Rndm() ; | |
395 | if ( ran <= 0.9984 ) | |
3a4295ee | 396 | rv = AliPHOSFastRecParticle::kNEUTRALHASLOW ; |
b1aa729d | 397 | else |
3a4295ee | 398 | rv = AliPHOSFastRecParticle::kNEUTRALEMSLOW ; |
b1aa729d | 399 | break ; |
400 | ||
401 | case 11: // it's a electron | |
402 | ran = fRan.Rndm() ; | |
403 | if ( ran <= 0.9996 ) | |
3a4295ee | 404 | rv = AliPHOSFastRecParticle::kCHARGEDEMFAST ; |
b1aa729d | 405 | else |
3a4295ee | 406 | rv = AliPHOSFastRecParticle::kCHARGEDHAFAST ; |
b1aa729d | 407 | break; |
408 | ||
f96d3dc7 | 409 | case -11: // it's a positon |
b1aa729d | 410 | ran = fRan.Rndm() ; |
411 | if ( ran <= 0.9996 ) | |
3a4295ee | 412 | rv = AliPHOSFastRecParticle::kCHARGEDEMFAST ; |
b1aa729d | 413 | else |
3a4295ee | 414 | rv = AliPHOSFastRecParticle::kCHARGEDHAFAST ; |
b1aa729d | 415 | break; |
416 | ||
417 | case -1: // it's a charged | |
418 | ran = fRan.Rndm() ; | |
419 | if ( ran <= 0.9996 ) | |
3a4295ee | 420 | rv = AliPHOSFastRecParticle::kCHARGEDHAFAST ; |
b1aa729d | 421 | else |
3a4295ee | 422 | rv = AliPHOSFastRecParticle::kNEUTRALHAFAST ; |
b1aa729d | 423 | |
424 | break ; | |
425 | } | |
426 | ||
427 | ||
a73f33f0 | 428 | return rv ; |
429 | } | |
430 | ||
f96d3dc7 | 431 | //___________________________________________________________________________ |
432 | void AliPHOSvFast::ResetPoints() | |
433 | { | |
b2a60966 | 434 | // This overloads the method in AliDetector |
435 | ||
f96d3dc7 | 436 | ResetFastRecParticles() ; |
437 | } | |
438 | ||
439 | //___________________________________________________________________________ | |
440 | void AliPHOSvFast::ResetFastRecParticles() | |
441 | { | |
b2a60966 | 442 | // Resets the list of virtual reconstructed particles |
443 | ||
f96d3dc7 | 444 | if (fFastRecParticles) |
445 | fFastRecParticles->Clear() ; | |
446 | fNRecParticles = 0 ; | |
447 | } | |
448 | ||
3decf5cb | 449 | //___________________________________________________________________________ |
450 | void AliPHOSvFast::SetBigBox(Int_t index, Float_t value) | |
451 | { | |
b2a60966 | 452 | // Set the size of the Box describing a PHOS module |
453 | ||
3decf5cb | 454 | switch (index) { |
455 | case 0: | |
456 | fBigBoxX = value ; | |
457 | break ; | |
458 | case 1: | |
459 | fBigBoxY = value ; | |
460 | break ; | |
461 | case 2: | |
462 | fBigBoxZ = value ; | |
463 | break ; | |
464 | } | |
465 | ||
466 | } | |
467 | ||
a73f33f0 | 468 | //____________________________________________________________________________ |
469 | Double_t AliPHOSvFast::SigmaE(Double_t energy) | |
470 | { | |
b2a60966 | 471 | // Calculates the energy dependent energy resolution |
472 | ||
a73f33f0 | 473 | Double_t rv = -1 ; |
474 | ||
475 | rv = TMath::Sqrt( TMath::Power(fResPara1/energy, 2) | |
476 | + TMath::Power(fResPara2/TMath::Sqrt(energy), 2) | |
477 | + TMath::Power(fResPara3, 2) ) ; | |
478 | ||
479 | return rv * energy ; | |
480 | } | |
481 | ||
b1aa729d | 482 | //____________________________________________________________________________ |
7a9d98f9 | 483 | Double_t AliPHOSvFast::SigmaP(Double_t energy, Double_t incidence) |
b1aa729d | 484 | { |
b2a60966 | 485 | // Calculates the energy dependent position resolution |
486 | ||
b1aa729d | 487 | Double_t paraA = fPosParaA0 + fPosParaA1 * incidence ; |
488 | Double_t paraB = fPosParaB0 + fPosParaB1 * incidence + fPosParaB2 * incidence * incidence ; | |
489 | ||
490 | return ( paraA / TMath::Sqrt(energy) + paraB ) * 0.1 ; // in cm | |
491 | } | |
492 | ||
3decf5cb | 493 | //____________________________________________________________________________ |
494 | void AliPHOSvFast::StepManager(void) | |
495 | { | |
b2a60966 | 496 | // Only verifies if the particle reaches PHOS and stops the tracking |
3a4295ee | 497 | |
a73f33f0 | 498 | TLorentzVector lv ; |
499 | gMC->TrackPosition(lv) ; | |
b1aa729d | 500 | TVector3 pos = lv.Vect() ; |
501 | Int_t modid ; | |
502 | gMC->CurrentVolID(modid); | |
a73f33f0 | 503 | |
3a4295ee | 504 | Float_t energy = gMC->Etot() ; //Total energy of current track |
3decf5cb | 505 | |
3a4295ee | 506 | //Calculating mass of current particle |
507 | TDatabasePDG * pdg = TDatabasePDG::Instance() ; | |
508 | TParticlePDG * partPDG = pdg->GetParticle(gMC->TrackPid()) ; | |
509 | Float_t mass = partPDG->Mass() ; | |
a73f33f0 | 510 | |
3a4295ee | 511 | if(energy > mass){ |
512 | pos.SetMag(TMath::Sqrt(energy*energy-mass*mass)) ; | |
513 | TLorentzVector pTrack(pos, energy) ; | |
a73f33f0 | 514 | |
3a4295ee | 515 | TParticle * part = new TParticle(gMC->TrackPid(), 0,-1,-1,-1,-1, pTrack, lv) ; |
516 | ||
517 | AliPHOSFastRecParticle rp(*part) ; | |
b1aa729d | 518 | |
3a4295ee | 519 | // Adds the response of PHOS to the particle |
520 | MakeRecParticle(modid, pos, rp) ; | |
521 | ||
522 | // add the `track' particle to the FastRecParticles list | |
b1aa729d | 523 | |
3a4295ee | 524 | AddRecParticle(rp) ; |
a73f33f0 | 525 | |
3a4295ee | 526 | part->Delete() ; |
527 | } | |
a73f33f0 | 528 | // stop the track as soon PHOS is reached |
b1aa729d | 529 | |
3decf5cb | 530 | gMC->StopTrack() ; |
531 | ||
532 | } | |
533 |