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4c039060 | 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 | ||
88cb7938 | 16 | /* $Id$ */ |
4c039060 | 17 | |
fe4da5cc | 18 | /////////////////////////////////////////////////////////////////////////////// |
19 | // // | |
769257f4 | 20 | // Transition Radiation Detector version 1 -- slow simulator // |
fe4da5cc | 21 | // // |
22 | //Begin_Html | |
23 | /* | |
5c7f4665 | 24 | <img src="picts/AliTRDfullClass.gif"> |
fe4da5cc | 25 | */ |
26 | //End_Html | |
27 | // // | |
28 | // // | |
29 | /////////////////////////////////////////////////////////////////////////////// | |
30 | ||
769257f4 | 31 | #include <stdlib.h> |
32 | ||
793ff80c | 33 | #include <TF1.h> |
1819f4bb | 34 | #include <TLorentzVector.h> |
88cb7938 | 35 | #include <TMath.h> |
36 | #include <TRandom.h> | |
37 | #include <TVector.h> | |
38 | #include <TVirtualMC.h> | |
fe4da5cc | 39 | |
d3f347ff | 40 | #include "AliConst.h" |
45160b1f | 41 | #include "AliLog.h" |
42 | #include "AliMC.h" | |
88cb7938 | 43 | #include "AliRun.h" |
44 | #include "AliTRDgeometry.h" | |
793ff80c | 45 | #include "AliTRDhit.h" |
793ff80c | 46 | #include "AliTRDsim.h" |
88cb7938 | 47 | #include "AliTRDv1.h" |
851d3db9 | 48 | |
fe4da5cc | 49 | ClassImp(AliTRDv1) |
8230f242 | 50 | |
51 | //_____________________________________________________________________________ | |
52 | AliTRDv1::AliTRDv1():AliTRD() | |
53 | { | |
54 | // | |
55 | // Default constructor | |
56 | // | |
57 | ||
a328fff9 | 58 | fSensSelect = 0; |
59 | fSensPlane = -1; | |
60 | fSensChamber = -1; | |
61 | fSensSector = -1; | |
62 | fSensSectorRange = 0; | |
8230f242 | 63 | |
a328fff9 | 64 | fDeltaE = NULL; |
65 | fDeltaG = NULL; | |
66 | fTR = NULL; | |
bd0f8685 | 67 | fTRon = kFALSE; |
a328fff9 | 68 | |
69 | fStepSize = 0.1; | |
c4214bc0 | 70 | fTypeOfStepManager = 1; |
8230f242 | 71 | |
72 | } | |
73 | ||
fe4da5cc | 74 | //_____________________________________________________________________________ |
75 | AliTRDv1::AliTRDv1(const char *name, const char *title) | |
76 | :AliTRD(name, title) | |
77 | { | |
78 | // | |
851d3db9 | 79 | // Standard constructor for Transition Radiation Detector version 1 |
fe4da5cc | 80 | // |
82bbf98a | 81 | |
a328fff9 | 82 | fSensSelect = 0; |
83 | fSensPlane = -1; | |
84 | fSensChamber = -1; | |
85 | fSensSector = -1; | |
86 | fSensSectorRange = 0; | |
5c7f4665 | 87 | |
a328fff9 | 88 | fDeltaE = NULL; |
89 | fDeltaG = NULL; | |
90 | fTR = NULL; | |
bd0f8685 | 91 | fTRon = kTRUE; |
a328fff9 | 92 | fStepSize = 0.1; |
c4214bc0 | 93 | fTypeOfStepManager = 1; |
5c7f4665 | 94 | |
95 | SetBufferSize(128000); | |
96 | ||
97 | } | |
98 | ||
8230f242 | 99 | //_____________________________________________________________________________ |
73ae7b59 | 100 | AliTRDv1::AliTRDv1(const AliTRDv1 &trd):AliTRD(trd) |
8230f242 | 101 | { |
102 | // | |
103 | // Copy constructor | |
104 | // | |
105 | ||
dd9a6ee3 | 106 | ((AliTRDv1 &) trd).Copy(*this); |
8230f242 | 107 | |
108 | } | |
109 | ||
5c7f4665 | 110 | //_____________________________________________________________________________ |
111 | AliTRDv1::~AliTRDv1() | |
112 | { | |
dd9a6ee3 | 113 | // |
114 | // AliTRDv1 destructor | |
115 | // | |
82bbf98a | 116 | |
5c7f4665 | 117 | if (fDeltaE) delete fDeltaE; |
a328fff9 | 118 | if (fDeltaG) delete fDeltaG; |
793ff80c | 119 | if (fTR) delete fTR; |
82bbf98a | 120 | |
fe4da5cc | 121 | } |
122 | ||
dd9a6ee3 | 123 | //_____________________________________________________________________________ |
124 | AliTRDv1 &AliTRDv1::operator=(const AliTRDv1 &trd) | |
125 | { | |
126 | // | |
127 | // Assignment operator | |
128 | // | |
129 | ||
130 | if (this != &trd) ((AliTRDv1 &) trd).Copy(*this); | |
131 | return *this; | |
132 | ||
133 | } | |
8230f242 | 134 | |
135 | //_____________________________________________________________________________ | |
e0d47c25 | 136 | void AliTRDv1::Copy(TObject &trd) const |
8230f242 | 137 | { |
c4214bc0 | 138 | printf("void AliTRDv1::Copy(TObject &trd) const\n"); |
8230f242 | 139 | // |
140 | // Copy function | |
141 | // | |
142 | ||
a328fff9 | 143 | ((AliTRDv1 &) trd).fSensSelect = fSensSelect; |
144 | ((AliTRDv1 &) trd).fSensPlane = fSensPlane; | |
145 | ((AliTRDv1 &) trd).fSensChamber = fSensChamber; | |
146 | ((AliTRDv1 &) trd).fSensSector = fSensSector; | |
147 | ((AliTRDv1 &) trd).fSensSectorRange = fSensSectorRange; | |
148 | ||
149 | ((AliTRDv1 &) trd).fTypeOfStepManager = fTypeOfStepManager; | |
150 | ((AliTRDv1 &) trd).fStepSize = fStepSize; | |
8230f242 | 151 | |
bd0f8685 | 152 | ((AliTRDv1 &) trd).fTRon = fTRon; |
153 | ||
793ff80c | 154 | fDeltaE->Copy(*((AliTRDv1 &) trd).fDeltaE); |
a328fff9 | 155 | fDeltaG->Copy(*((AliTRDv1 &) trd).fDeltaG); |
793ff80c | 156 | fTR->Copy(*((AliTRDv1 &) trd).fTR); |
8230f242 | 157 | |
158 | } | |
159 | ||
fe4da5cc | 160 | //_____________________________________________________________________________ |
161 | void AliTRDv1::CreateGeometry() | |
162 | { | |
163 | // | |
851d3db9 | 164 | // Create the GEANT geometry for the Transition Radiation Detector - Version 1 |
5c7f4665 | 165 | // This version covers the full azimuth. |
d3f347ff | 166 | // |
167 | ||
82bbf98a | 168 | // Check that FRAME is there otherwise we have no place where to put the TRD |
8230f242 | 169 | AliModule* frame = gAlice->GetModule("FRAME"); |
170 | if (!frame) return; | |
d3f347ff | 171 | |
82bbf98a | 172 | // Define the chambers |
173 | AliTRD::CreateGeometry(); | |
d3f347ff | 174 | |
fe4da5cc | 175 | } |
176 | ||
177 | //_____________________________________________________________________________ | |
178 | void AliTRDv1::CreateMaterials() | |
179 | { | |
180 | // | |
851d3db9 | 181 | // Create materials for the Transition Radiation Detector version 1 |
fe4da5cc | 182 | // |
82bbf98a | 183 | |
d3f347ff | 184 | AliTRD::CreateMaterials(); |
82bbf98a | 185 | |
fe4da5cc | 186 | } |
187 | ||
793ff80c | 188 | //_____________________________________________________________________________ |
189 | void AliTRDv1::CreateTRhit(Int_t det) | |
190 | { | |
191 | // | |
192 | // Creates an electron cluster from a TR photon. | |
193 | // The photon is assumed to be created a the end of the radiator. The | |
194 | // distance after which it deposits its energy takes into account the | |
195 | // absorbtion of the entrance window and of the gas mixture in drift | |
196 | // volume. | |
197 | // | |
198 | ||
199 | // PDG code electron | |
200 | const Int_t kPdgElectron = 11; | |
201 | ||
202 | // Ionization energy | |
bc327ce2 | 203 | const Float_t kWion = 23.53; |
793ff80c | 204 | |
205 | // Maximum number of TR photons per track | |
206 | const Int_t kNTR = 50; | |
207 | ||
208 | TLorentzVector mom, pos; | |
793ff80c | 209 | |
793ff80c | 210 | // Create TR at the entrance of the chamber |
211 | if (gMC->IsTrackEntering()) { | |
212 | ||
f73816f5 | 213 | // Create TR only for electrons |
214 | Int_t iPdg = gMC->TrackPid(); | |
215 | if (TMath::Abs(iPdg) != kPdgElectron) return; | |
216 | ||
793ff80c | 217 | Float_t eTR[kNTR]; |
218 | Int_t nTR; | |
219 | ||
220 | // Create TR photons | |
221 | gMC->TrackMomentum(mom); | |
222 | Float_t pTot = mom.Rho(); | |
223 | fTR->CreatePhotons(iPdg,pTot,nTR,eTR); | |
224 | if (nTR > kNTR) { | |
45160b1f | 225 | AliFatal(Form("Boundary error: nTR = %d, kNTR = %d",nTR,kNTR)); |
793ff80c | 226 | } |
227 | ||
228 | // Loop through the TR photons | |
229 | for (Int_t iTR = 0; iTR < nTR; iTR++) { | |
230 | ||
231 | Float_t energyMeV = eTR[iTR] * 0.001; | |
232 | Float_t energyeV = eTR[iTR] * 1000.0; | |
233 | Float_t absLength = 0; | |
234 | Float_t sigma = 0; | |
235 | ||
236 | // Take the absorbtion in the entrance window into account | |
237 | Double_t muMy = fTR->GetMuMy(energyMeV); | |
238 | sigma = muMy * fFoilDensity; | |
842287f2 | 239 | if (sigma > 0.0) { |
240 | absLength = gRandom->Exp(1.0/sigma); | |
241 | if (absLength < AliTRDgeometry::MyThick()) continue; | |
242 | } | |
243 | else { | |
244 | continue; | |
245 | } | |
793ff80c | 246 | |
247 | // The absorbtion cross sections in the drift gas | |
3dac2b2d | 248 | // Gas-mixture (Xe/CO2) |
249 | Double_t muXe = fTR->GetMuXe(energyMeV); | |
250 | Double_t muCO = fTR->GetMuCO(energyMeV); | |
251 | sigma = (0.85 * muXe + 0.15 * muCO) * fGasDensity * fTR->GetTemp(); | |
793ff80c | 252 | |
253 | // The distance after which the energy of the TR photon | |
254 | // is deposited. | |
842287f2 | 255 | if (sigma > 0.0) { |
256 | absLength = gRandom->Exp(1.0/sigma); | |
a328fff9 | 257 | if (absLength > (AliTRDgeometry::DrThick() |
258 | + AliTRDgeometry::AmThick())) { | |
259 | continue; | |
260 | } | |
842287f2 | 261 | } |
262 | else { | |
263 | continue; | |
264 | } | |
793ff80c | 265 | |
266 | // The position of the absorbtion | |
267 | Float_t posHit[3]; | |
268 | gMC->TrackPosition(pos); | |
269 | posHit[0] = pos[0] + mom[0] / pTot * absLength; | |
270 | posHit[1] = pos[1] + mom[1] / pTot * absLength; | |
c4214bc0 | 271 | posHit[2] = pos[2] + mom[2] / pTot * absLength; |
793ff80c | 272 | |
273 | // Create the charge | |
274 | Int_t q = ((Int_t) (energyeV / kWion)); | |
275 | ||
276 | // Add the hit to the array. TR photon hits are marked | |
277 | // by negative charge | |
c4214bc0 | 278 | AddHit(gAlice->GetMCApp()->GetCurrentTrackNumber(),det,posHit,-q,kTRUE); |
793ff80c | 279 | |
280 | } | |
281 | ||
282 | } | |
283 | ||
284 | } | |
285 | ||
5c7f4665 | 286 | //_____________________________________________________________________________ |
287 | void AliTRDv1::Init() | |
288 | { | |
289 | // | |
290 | // Initialise Transition Radiation Detector after geometry has been built. | |
5c7f4665 | 291 | // |
292 | ||
293 | AliTRD::Init(); | |
294 | ||
45160b1f | 295 | AliDebug(1,"Slow simulator\n"); |
851d3db9 | 296 | if (fSensSelect) { |
297 | if (fSensPlane >= 0) | |
45160b1f | 298 | AliInfo(Form("Only plane %d is sensitive")); |
851d3db9 | 299 | if (fSensChamber >= 0) |
45160b1f | 300 | AliInfo(Form("Only chamber %d is sensitive",fSensChamber)); |
9d0b222b | 301 | if (fSensSector >= 0) { |
302 | Int_t sens1 = fSensSector; | |
303 | Int_t sens2 = fSensSector + fSensSectorRange; | |
793ff80c | 304 | sens2 -= ((Int_t) (sens2 / AliTRDgeometry::Nsect())) |
305 | * AliTRDgeometry::Nsect(); | |
45160b1f | 306 | AliInfo(Form("Only sectors %d - %d are sensitive\n",sens1,sens2-1)); |
9d0b222b | 307 | } |
851d3db9 | 308 | } |
bd0f8685 | 309 | |
310 | // Switch on TR simulation as default | |
311 | if (!fTRon) { | |
45160b1f | 312 | AliInfo("TR simulation off"); |
bd0f8685 | 313 | } |
314 | else { | |
315 | fTR = new AliTRDsim(); | |
316 | } | |
5c7f4665 | 317 | |
318 | // First ionization potential (eV) for the gas mixture (90% Xe + 10% CO2) | |
319 | const Float_t kPoti = 12.1; | |
320 | // Maximum energy (50 keV); | |
321 | const Float_t kEend = 50000.0; | |
322 | // Ermilova distribution for the delta-ray spectrum | |
8230f242 | 323 | Float_t poti = TMath::Log(kPoti); |
324 | Float_t eEnd = TMath::Log(kEend); | |
a328fff9 | 325 | |
326 | // Ermilova distribution for the delta-ray spectrum | |
c4214bc0 | 327 | fDeltaE = new TF1("deltae" ,Ermilova ,poti,eEnd,0); |
a328fff9 | 328 | |
329 | // Geant3 distribution for the delta-ray spectrum | |
c4214bc0 | 330 | fDeltaG = new TF1("deltag",IntSpecGeant,2.421257,28.536469,0); |
5c7f4665 | 331 | |
45160b1f | 332 | AliDebug(1,"+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++"); |
5c7f4665 | 333 | |
fe4da5cc | 334 | } |
335 | ||
5c7f4665 | 336 | //_____________________________________________________________________________ |
337 | void AliTRDv1::SetSensPlane(Int_t iplane) | |
338 | { | |
339 | // | |
851d3db9 | 340 | // Defines the hit-sensitive plane (0-5) |
5c7f4665 | 341 | // |
82bbf98a | 342 | |
851d3db9 | 343 | if ((iplane < 0) || (iplane > 5)) { |
45160b1f | 344 | AliWarning(Form("Wrong input value:%d",iplane)); |
345 | AliWarning("Use standard setting"); | |
851d3db9 | 346 | fSensPlane = -1; |
347 | fSensSelect = 0; | |
5c7f4665 | 348 | return; |
349 | } | |
82bbf98a | 350 | |
5c7f4665 | 351 | fSensSelect = 1; |
352 | fSensPlane = iplane; | |
82bbf98a | 353 | |
5c7f4665 | 354 | } |
355 | ||
356 | //_____________________________________________________________________________ | |
357 | void AliTRDv1::SetSensChamber(Int_t ichamber) | |
358 | { | |
359 | // | |
851d3db9 | 360 | // Defines the hit-sensitive chamber (0-4) |
5c7f4665 | 361 | // |
362 | ||
851d3db9 | 363 | if ((ichamber < 0) || (ichamber > 4)) { |
45160b1f | 364 | AliWarning(Form("Wrong input value: %d",ichamber)); |
365 | AliWarning("Use standard setting"); | |
851d3db9 | 366 | fSensChamber = -1; |
367 | fSensSelect = 0; | |
5c7f4665 | 368 | return; |
369 | } | |
370 | ||
371 | fSensSelect = 1; | |
372 | fSensChamber = ichamber; | |
373 | ||
374 | } | |
375 | ||
376 | //_____________________________________________________________________________ | |
377 | void AliTRDv1::SetSensSector(Int_t isector) | |
378 | { | |
379 | // | |
851d3db9 | 380 | // Defines the hit-sensitive sector (0-17) |
5c7f4665 | 381 | // |
382 | ||
9d0b222b | 383 | SetSensSector(isector,1); |
384 | ||
385 | } | |
386 | ||
387 | //_____________________________________________________________________________ | |
388 | void AliTRDv1::SetSensSector(Int_t isector, Int_t nsector) | |
389 | { | |
390 | // | |
391 | // Defines a range of hit-sensitive sectors. The range is defined by | |
392 | // <isector> (0-17) as the starting point and <nsector> as the number | |
393 | // of sectors to be included. | |
394 | // | |
395 | ||
851d3db9 | 396 | if ((isector < 0) || (isector > 17)) { |
45160b1f | 397 | AliWarning(Form("Wrong input value <isector>: %d",isector)); |
398 | AliWarning("Use standard setting"); | |
9d0b222b | 399 | fSensSector = -1; |
400 | fSensSectorRange = 0; | |
401 | fSensSelect = 0; | |
5c7f4665 | 402 | return; |
403 | } | |
404 | ||
9d0b222b | 405 | if ((nsector < 1) || (nsector > 18)) { |
45160b1f | 406 | AliWarning(Form("Wrong input value <nsector>: %d",nsector)); |
407 | AliWarning("Use standard setting"); | |
9d0b222b | 408 | fSensSector = -1; |
409 | fSensSectorRange = 0; | |
410 | fSensSelect = 0; | |
411 | return; | |
412 | } | |
413 | ||
414 | fSensSelect = 1; | |
415 | fSensSector = isector; | |
416 | fSensSectorRange = nsector; | |
5c7f4665 | 417 | |
418 | } | |
419 | ||
420 | //_____________________________________________________________________________ | |
421 | void AliTRDv1::StepManager() | |
a328fff9 | 422 | { |
423 | // | |
c4214bc0 | 424 | // Slow simulator. Every charged track produces electron cluster as hits |
a328fff9 | 425 | // along its path across the drift volume. |
426 | // | |
427 | ||
428 | switch (fTypeOfStepManager) { | |
429 | case 0 : StepManagerErmilova(); break; // 0 is Ermilova | |
430 | case 1 : StepManagerGeant(); break; // 1 is Geant | |
431 | case 2 : StepManagerFixedStep(); break; // 2 is fixed step | |
45160b1f | 432 | default : AliWarning("Not a valid Step Manager."); |
a328fff9 | 433 | } |
434 | ||
435 | } | |
436 | ||
437 | //_____________________________________________________________________________ | |
438 | void AliTRDv1::SelectStepManager(Int_t t) | |
439 | { | |
440 | // | |
441 | // Selects a step manager type: | |
442 | // 0 - Ermilova | |
443 | // 1 - Geant3 | |
444 | // 2 - Fixed step size | |
445 | // | |
446 | ||
c4214bc0 | 447 | /* if (t == 1) { |
45160b1f | 448 | AliWarning("Sorry, Geant parametrization step manager is not implemented yet. Please ask K.Oyama for detail."); |
a328fff9 | 449 | } |
c4214bc0 | 450 | */ |
a328fff9 | 451 | fTypeOfStepManager = t; |
45160b1f | 452 | AliInfo(Form("Step Manager type %d was selected",fTypeOfStepManager)); |
a328fff9 | 453 | |
454 | } | |
455 | ||
456 | //_____________________________________________________________________________ | |
457 | void AliTRDv1::StepManagerGeant() | |
458 | { | |
459 | // | |
c4214bc0 | 460 | // Slow simulator. Every charged track produces electron cluster as hits |
a328fff9 | 461 | // along its path across the drift volume. The step size is set acording |
462 | // to Bethe-Bloch. The energy distribution of the delta electrons follows | |
463 | // a spectrum taken from Geant3. | |
464 | // | |
c4214bc0 | 465 | Int_t pla = 0; |
466 | Int_t cha = 0; | |
467 | Int_t sec = 0; | |
468 | Int_t det = 0; | |
469 | Int_t iPdg; | |
470 | Int_t qTot; | |
471 | ||
472 | Float_t hits[3]; | |
473 | Float_t charge; | |
474 | Float_t aMass; | |
475 | ||
476 | Double_t pTot = 0; | |
477 | Double_t eDelta; | |
478 | Double_t betaGamma, pp; | |
479 | Double_t stepSize=0; | |
480 | ||
481 | Bool_t drRegion = kFALSE; | |
482 | Bool_t amRegion = kFALSE; | |
483 | ||
484 | TString cIdCurrent; | |
485 | TString cIdSensDr = "J"; | |
486 | TString cIdSensAm = "K"; | |
487 | Char_t cIdChamber[3]; | |
488 | cIdChamber[2] = 0; | |
489 | ||
490 | TLorentzVector pos, mom; | |
491 | ||
492 | const Int_t kNplan = AliTRDgeometry::Nplan(); | |
493 | const Int_t kNcham = AliTRDgeometry::Ncham(); | |
494 | const Int_t kNdetsec = kNplan * kNcham; | |
495 | ||
496 | const Double_t kBig = 1.0E+12; // Infinitely big | |
bc327ce2 | 497 | const Float_t kWion = 23.53; // Ionization energy |
c4214bc0 | 498 | const Float_t kPTotMaxEl = 0.002; // Maximum momentum for e+ e- g |
499 | ||
500 | // Minimum energy for the step size adjustment | |
501 | const Float_t kEkinMinStep = 1.0e-5; | |
502 | // energy threshold for production of delta electrons | |
503 | const Float_t kECut = 1.0e4; | |
504 | // Parameters entering the parametrized range for delta electrons | |
505 | const float ra=5.37E-4, rb=0.9815, rc=3.123E-3; | |
506 | // Gas density -> To be made user adjustable ! | |
507 | const float rho=0.004945 ; //[0.85*0.00549+0.15*0.00186 (Xe-CO2 85-15)] | |
a328fff9 | 508 | |
c4214bc0 | 509 | // Plateau value of the energy-loss for electron in xenon |
510 | // taken from: Allison + Comb, Ann. Rev. Nucl. Sci. (1980), 30, 253 | |
511 | //const Double_t kPlateau = 1.70; | |
512 | // the averaged value (26/3/99) | |
513 | const Float_t kPlateau = 1.55; | |
514 | ||
515 | const Float_t kPrim = 19.34; // dN1/dx|min for the gas mixture (90% Xe + 10% CO2) | |
516 | // First ionization potential (eV) for the gas mixture (90% Xe + 10% CO2) | |
517 | const Float_t kPoti = 12.1; | |
518 | ||
519 | const Int_t kPdgElectron = 11; // PDG code electron | |
520 | ||
521 | // Set the maximum step size to a very large number for all | |
522 | // neutral particles and those outside the driftvolume | |
523 | gMC->SetMaxStep(kBig); | |
524 | ||
525 | // Use only charged tracks | |
526 | if (( gMC->TrackCharge() ) && | |
527 | (!gMC->IsTrackStop() ) && | |
528 | (!gMC->IsTrackDisappeared())) { | |
529 | ||
530 | // Inside a sensitive volume? | |
531 | drRegion = kFALSE; | |
532 | amRegion = kFALSE; | |
533 | cIdCurrent = gMC->CurrentVolName(); | |
534 | if (cIdSensDr == cIdCurrent[1]) { | |
535 | drRegion = kTRUE; | |
536 | } | |
537 | if (cIdSensAm == cIdCurrent[1]) { | |
538 | amRegion = kTRUE; | |
539 | } | |
540 | if (drRegion || amRegion) { | |
a328fff9 | 541 | |
c4214bc0 | 542 | // The hit coordinates and charge |
543 | gMC->TrackPosition(pos); | |
544 | hits[0] = pos[0]; | |
545 | hits[1] = pos[1]; | |
546 | hits[2] = pos[2]; | |
547 | ||
548 | // The sector number (0 - 17) | |
549 | // The numbering goes clockwise and starts at y = 0 | |
550 | Float_t phi = kRaddeg*TMath::ATan2(pos[0],pos[1]); | |
551 | if (phi < 90.) | |
552 | phi = phi + 270.; | |
553 | else | |
554 | phi = phi - 90.; | |
555 | sec = ((Int_t) (phi / 20)); | |
556 | ||
557 | // The plane and chamber number | |
558 | cIdChamber[0] = cIdCurrent[2]; | |
559 | cIdChamber[1] = cIdCurrent[3]; | |
560 | Int_t idChamber = (atoi(cIdChamber) % kNdetsec); | |
561 | cha = kNcham - ((Int_t) idChamber / kNplan) - 1; | |
562 | pla = ((Int_t) idChamber % kNplan); | |
563 | ||
564 | // Check on selected volumes | |
565 | Int_t addthishit = 1; | |
566 | if (fSensSelect) { | |
567 | if ((fSensPlane >= 0) && (pla != fSensPlane )) addthishit = 0; | |
568 | if ((fSensChamber >= 0) && (cha != fSensChamber)) addthishit = 0; | |
569 | if (fSensSector >= 0) { | |
570 | Int_t sens1 = fSensSector; | |
571 | Int_t sens2 = fSensSector + fSensSectorRange; | |
572 | sens2 -= ((Int_t) (sens2 / AliTRDgeometry::Nsect())) | |
573 | * AliTRDgeometry::Nsect(); | |
574 | if (sens1 < sens2) { | |
575 | if ((sec < sens1) || (sec >= sens2)) addthishit = 0; | |
576 | } | |
577 | else { | |
578 | if ((sec < sens1) && (sec >= sens2)) addthishit = 0; | |
579 | } | |
580 | } | |
581 | } | |
582 | ||
583 | // Add this hit | |
584 | if (addthishit) { | |
585 | ||
586 | // The detector number | |
587 | det = fGeometry->GetDetector(pla,cha,sec); | |
588 | ||
589 | // Special hits only in the drift region | |
590 | if (drRegion) { | |
591 | // Create a track reference at the entrance and | |
592 | // exit of each chamber that contain the | |
593 | // momentum components of the particle | |
594 | if (gMC->IsTrackEntering() || gMC->IsTrackExiting()) { | |
595 | gMC->TrackMomentum(mom); | |
596 | AddTrackReference(gAlice->GetMCApp()->GetCurrentTrackNumber()); | |
597 | } | |
598 | ||
599 | if (gMC->IsTrackEntering() && !gMC->IsNewTrack()) { | |
600 | // determine if hit belong to primary track | |
601 | fPrimaryTrackPid=gAlice->GetMCApp()->GetCurrentTrackNumber(); | |
602 | //determine track length when entering the detector | |
603 | fTrackLength0=gMC->TrackLength(); | |
604 | } | |
605 | ||
606 | // Create the hits from TR photons | |
607 | if (fTR) CreateTRhit(det); | |
608 | } | |
609 | ||
610 | // Calculate the energy of the delta-electrons | |
611 | // modified by Alex Bercuci (A.Bercuci@gsi.de) on 26.01.06 | |
612 | // take into account correlation with the underlying GEANT tracking | |
613 | // mechanism. see | |
614 | // http://www-linux.gsi.de/~abercuci/Contributions/TRD/index.html | |
615 | ||
616 | // determine the most significant process (last on the processes list) | |
617 | // which caused this hit | |
618 | TArrayI processes; | |
619 | gMC->StepProcesses(processes); | |
620 | int nofprocesses=processes.GetSize(), pid; | |
621 | if(!nofprocesses) pid=0; | |
622 | else pid= processes[nofprocesses-1]; | |
623 | ||
624 | // generate Edep according to GEANT parametrisation | |
625 | eDelta =TMath::Exp(fDeltaG->GetRandom()) - kPoti; | |
626 | eDelta=TMath::Max(eDelta,0.0); | |
627 | float pr_range=0.; | |
628 | float range=gMC->TrackLength()-fTrackLength0; | |
629 | // merge GEANT tracker information with localy cooked one | |
630 | if(gAlice->GetMCApp()->GetCurrentTrackNumber()==fPrimaryTrackPid) { | |
631 | // printf("primary pid=%d eDelta=%f\n",pid,eDelta); | |
632 | if(pid==27){ | |
633 | if(eDelta>=kECut){ | |
634 | pr_range=ra*eDelta*.001*(1.-rb/(1.+rc*eDelta*0.001))/rho; | |
635 | if(pr_range>=(3.7-range)) eDelta*=.1; | |
636 | } | |
637 | } else if(pid==1){ | |
638 | if(eDelta<kECut) eDelta*=.5; | |
639 | else { | |
640 | pr_range=ra*eDelta*.001*(1.-rb/(1.+rc*eDelta*0.001))/rho; | |
641 | if(pr_range>=((AliTRDgeometry::DrThick() | |
642 | + AliTRDgeometry::AmThick())-range)) eDelta*=.05; | |
643 | else eDelta*=.5; | |
644 | } | |
645 | } else eDelta=0.; | |
646 | } else eDelta=0.; | |
647 | ||
648 | // Generate the electron cluster size | |
649 | if(eDelta==0.) qTot=0; | |
650 | else qTot = ((Int_t) (eDelta / kWion) + 1); | |
651 | // Create a new dEdx hit | |
652 | AddHit(gAlice->GetMCApp()->GetCurrentTrackNumber(),det,hits,qTot, drRegion); | |
653 | ||
654 | // Calculate the maximum step size for the next tracking step | |
655 | // Produce only one hit if Ekin is below cutoff | |
656 | aMass = gMC->TrackMass(); | |
657 | if ((gMC->Etot() - aMass) > kEkinMinStep) { | |
658 | ||
659 | // The energy loss according to Bethe Bloch | |
660 | iPdg = TMath::Abs(gMC->TrackPid()); | |
661 | if ( (iPdg != kPdgElectron) || | |
662 | ((iPdg == kPdgElectron) && (pTot < kPTotMaxEl))) { | |
663 | gMC->TrackMomentum(mom); | |
664 | pTot = mom.Rho(); | |
665 | betaGamma = pTot / aMass; | |
666 | pp = BetheBlochGeant(betaGamma); | |
667 | // Take charge > 1 into account | |
668 | charge = gMC->TrackCharge(); | |
669 | if (TMath::Abs(charge) > 1) pp = pp * charge*charge; | |
670 | } else { // Electrons above 20 Mev/c are at the plateau | |
671 | pp = kPrim * kPlateau; | |
672 | } | |
673 | ||
1b775a44 | 674 | Int_t nsteps = 0; |
675 | do {nsteps = gRandom->Poisson(pp);} while(!nsteps); | |
676 | stepSize = 1./nsteps; | |
677 | gMC->SetMaxStep(stepSize); | |
678 | } | |
c4214bc0 | 679 | } |
680 | } | |
681 | } | |
a328fff9 | 682 | } |
683 | ||
684 | //_____________________________________________________________________________ | |
685 | void AliTRDv1::StepManagerErmilova() | |
5c7f4665 | 686 | { |
687 | // | |
5c7f4665 | 688 | // Slow simulator. Every charged track produces electron cluster as hits |
689 | // along its path across the drift volume. The step size is set acording | |
690 | // to Bethe-Bloch. The energy distribution of the delta electrons follows | |
691 | // a spectrum taken from Ermilova et al. | |
692 | // | |
693 | ||
851d3db9 | 694 | Int_t pla = 0; |
695 | Int_t cha = 0; | |
696 | Int_t sec = 0; | |
793ff80c | 697 | Int_t det = 0; |
851d3db9 | 698 | Int_t iPdg; |
793ff80c | 699 | Int_t qTot; |
5c7f4665 | 700 | |
793ff80c | 701 | Float_t hits[3]; |
a5cadd36 | 702 | Double_t random[1]; |
5c7f4665 | 703 | Float_t charge; |
704 | Float_t aMass; | |
705 | ||
f73816f5 | 706 | Double_t pTot = 0; |
5c7f4665 | 707 | Double_t eDelta; |
708 | Double_t betaGamma, pp; | |
f73816f5 | 709 | Double_t stepSize; |
5c7f4665 | 710 | |
332e9569 | 711 | Bool_t drRegion = kFALSE; |
712 | Bool_t amRegion = kFALSE; | |
713 | ||
714 | TString cIdCurrent; | |
715 | TString cIdSensDr = "J"; | |
716 | TString cIdSensAm = "K"; | |
593a9fc3 | 717 | Char_t cIdChamber[3]; |
718 | cIdChamber[2] = 0; | |
332e9569 | 719 | |
5c7f4665 | 720 | TLorentzVector pos, mom; |
82bbf98a | 721 | |
332e9569 | 722 | const Int_t kNplan = AliTRDgeometry::Nplan(); |
e644678a | 723 | const Int_t kNcham = AliTRDgeometry::Ncham(); |
724 | const Int_t kNdetsec = kNplan * kNcham; | |
725 | ||
a328fff9 | 726 | const Double_t kBig = 1.0E+12; // Infinitely big |
bc327ce2 | 727 | const Float_t kWion = 23.53; // Ionization energy |
a328fff9 | 728 | const Float_t kPTotMaxEl = 0.002; // Maximum momentum for e+ e- g |
5c7f4665 | 729 | |
c4214bc0 | 730 | // energy threshold for production of delta electrons |
731 | //const Float_t kECut = 1.0e4; | |
732 | // Parameters entering the parametrized range for delta electrons | |
733 | //const float ra=5.37E-4, rb=0.9815, rc=3.123E-3; | |
734 | // Gas density -> To be made user adjustable ! | |
735 | //const float rho=0.004945 ; //[0.85*0.00549+0.15*0.00186 (Xe-CO2 85-15)] | |
736 | ||
f73816f5 | 737 | // Minimum energy for the step size adjustment |
738 | const Float_t kEkinMinStep = 1.0e-5; | |
a328fff9 | 739 | |
5c7f4665 | 740 | // Plateau value of the energy-loss for electron in xenon |
741 | // taken from: Allison + Comb, Ann. Rev. Nucl. Sci. (1980), 30, 253 | |
742 | //const Double_t kPlateau = 1.70; | |
743 | // the averaged value (26/3/99) | |
a3c76cdc | 744 | const Float_t kPlateau = 1.55; |
a328fff9 | 745 | |
746 | const Float_t kPrim = 48.0; // dN1/dx|min for the gas mixture (90% Xe + 10% CO2) | |
5c7f4665 | 747 | // First ionization potential (eV) for the gas mixture (90% Xe + 10% CO2) |
a3c76cdc | 748 | const Float_t kPoti = 12.1; |
851d3db9 | 749 | |
a328fff9 | 750 | const Int_t kPdgElectron = 11; // PDG code electron |
5c7f4665 | 751 | |
752 | // Set the maximum step size to a very large number for all | |
753 | // neutral particles and those outside the driftvolume | |
754 | gMC->SetMaxStep(kBig); | |
755 | ||
756 | // Use only charged tracks | |
757 | if (( gMC->TrackCharge() ) && | |
758 | (!gMC->IsTrackStop() ) && | |
759 | (!gMC->IsTrackDisappeared())) { | |
fe4da5cc | 760 | |
5c7f4665 | 761 | // Inside a sensitive volume? |
332e9569 | 762 | drRegion = kFALSE; |
763 | amRegion = kFALSE; | |
764 | cIdCurrent = gMC->CurrentVolName(); | |
e6674585 | 765 | if (cIdSensDr == cIdCurrent[1]) { |
332e9569 | 766 | drRegion = kTRUE; |
767 | } | |
e6674585 | 768 | if (cIdSensAm == cIdCurrent[1]) { |
332e9569 | 769 | amRegion = kTRUE; |
770 | } | |
771 | if (drRegion || amRegion) { | |
fe4da5cc | 772 | |
5c7f4665 | 773 | // The hit coordinates and charge |
774 | gMC->TrackPosition(pos); | |
775 | hits[0] = pos[0]; | |
776 | hits[1] = pos[1]; | |
777 | hits[2] = pos[2]; | |
5c7f4665 | 778 | |
851d3db9 | 779 | // The sector number (0 - 17) |
780 | // The numbering goes clockwise and starts at y = 0 | |
e15eb584 | 781 | Float_t phi = kRaddeg*TMath::ATan2(pos[0],pos[1]); |
851d3db9 | 782 | if (phi < 90.) |
783 | phi = phi + 270.; | |
784 | else | |
785 | phi = phi - 90.; | |
786 | sec = ((Int_t) (phi / 20)); | |
82bbf98a | 787 | |
332e9569 | 788 | // The plane and chamber number |
789 | cIdChamber[0] = cIdCurrent[2]; | |
790 | cIdChamber[1] = cIdCurrent[3]; | |
e644678a | 791 | Int_t idChamber = (atoi(cIdChamber) % kNdetsec); |
a5cadd36 | 792 | cha = kNcham - ((Int_t) idChamber / kNplan) - 1; |
332e9569 | 793 | pla = ((Int_t) idChamber % kNplan); |
82bbf98a | 794 | |
5c7f4665 | 795 | // Check on selected volumes |
796 | Int_t addthishit = 1; | |
797 | if (fSensSelect) { | |
6f1e466d | 798 | if ((fSensPlane >= 0) && (pla != fSensPlane )) addthishit = 0; |
799 | if ((fSensChamber >= 0) && (cha != fSensChamber)) addthishit = 0; | |
9d0b222b | 800 | if (fSensSector >= 0) { |
801 | Int_t sens1 = fSensSector; | |
802 | Int_t sens2 = fSensSector + fSensSectorRange; | |
793ff80c | 803 | sens2 -= ((Int_t) (sens2 / AliTRDgeometry::Nsect())) |
804 | * AliTRDgeometry::Nsect(); | |
9d0b222b | 805 | if (sens1 < sens2) { |
806 | if ((sec < sens1) || (sec >= sens2)) addthishit = 0; | |
c4214bc0 | 807 | } |
9d0b222b | 808 | else { |
809 | if ((sec < sens1) && (sec >= sens2)) addthishit = 0; | |
c4214bc0 | 810 | } |
811 | } | |
5c7f4665 | 812 | } |
813 | ||
814 | // Add this hit | |
815 | if (addthishit) { | |
816 | ||
f73816f5 | 817 | // The detector number |
793ff80c | 818 | det = fGeometry->GetDetector(pla,cha,sec); |
819 | ||
a328fff9 | 820 | // Special hits only in the drift region |
332e9569 | 821 | if (drRegion) { |
f73816f5 | 822 | |
c61f1a66 | 823 | // Create a track reference at the entrance and |
824 | // exit of each chamber that contain the | |
825 | // momentum components of the particle | |
f73816f5 | 826 | if (gMC->IsTrackEntering() || gMC->IsTrackExiting()) { |
827 | gMC->TrackMomentum(mom); | |
5d12ce38 | 828 | AddTrackReference(gAlice->GetMCApp()->GetCurrentTrackNumber()); |
f73816f5 | 829 | } |
f73816f5 | 830 | // Create the hits from TR photons |
831 | if (fTR) CreateTRhit(det); | |
c4214bc0 | 832 | } |
f73816f5 | 833 | |
f73816f5 | 834 | |
835 | // Calculate the energy of the delta-electrons | |
836 | eDelta = TMath::Exp(fDeltaE->GetRandom()) - kPoti; | |
837 | eDelta = TMath::Max(eDelta,0.0); | |
c4214bc0 | 838 | // Generate the electron cluster size |
839 | if(eDelta==0.) qTot=0; | |
840 | else qTot = ((Int_t) (eDelta / kWion) + 1); | |
f73816f5 | 841 | |
c4214bc0 | 842 | // Create a new dEdx hit |
332e9569 | 843 | if (drRegion) { |
a328fff9 | 844 | AddHit(gAlice->GetMCApp()->GetCurrentTrackNumber() |
c4214bc0 | 845 | ,det,hits,qTot, kTRUE); |
846 | } | |
5c7f4665 | 847 | else { |
a328fff9 | 848 | AddHit(gAlice->GetMCApp()->GetCurrentTrackNumber() |
c4214bc0 | 849 | ,det,hits,qTot,kFALSE); |
850 | } | |
f73816f5 | 851 | |
5c7f4665 | 852 | // Calculate the maximum step size for the next tracking step |
f73816f5 | 853 | // Produce only one hit if Ekin is below cutoff |
854 | aMass = gMC->TrackMass(); | |
855 | if ((gMC->Etot() - aMass) > kEkinMinStep) { | |
856 | ||
857 | // The energy loss according to Bethe Bloch | |
858 | iPdg = TMath::Abs(gMC->TrackPid()); | |
859 | if ( (iPdg != kPdgElectron) || | |
c4214bc0 | 860 | ((iPdg == kPdgElectron) && (pTot < kPTotMaxEl))) { |
f73816f5 | 861 | gMC->TrackMomentum(mom); |
862 | pTot = mom.Rho(); | |
863 | betaGamma = pTot / aMass; | |
864 | pp = kPrim * BetheBloch(betaGamma); | |
865 | // Take charge > 1 into account | |
866 | charge = gMC->TrackCharge(); | |
867 | if (TMath::Abs(charge) > 1) pp = pp * charge*charge; | |
c4214bc0 | 868 | } else { // Electrons above 20 Mev/c are at the plateau |
869 | pp = kPrim * kPlateau; | |
f73816f5 | 870 | } |
871 | ||
872 | if (pp > 0) { | |
873 | do | |
b9d0a01d | 874 | gMC->GetRandom()->RndmArray(1, random); |
f73816f5 | 875 | while ((random[0] == 1.) || (random[0] == 0.)); |
876 | stepSize = - TMath::Log(random[0]) / pp; | |
877 | gMC->SetMaxStep(stepSize); | |
c4214bc0 | 878 | } |
879 | } | |
5c7f4665 | 880 | } |
d3f347ff | 881 | } |
5c7f4665 | 882 | } |
5c7f4665 | 883 | } |
884 | ||
a328fff9 | 885 | //_____________________________________________________________________________ |
886 | void AliTRDv1::StepManagerFixedStep() | |
887 | { | |
888 | // | |
889 | // Slow simulator. Every charged track produces electron cluster as hits | |
890 | // along its path across the drift volume. The step size is fixed in | |
891 | // this version of the step manager. | |
892 | // | |
893 | ||
894 | Int_t pla = 0; | |
895 | Int_t cha = 0; | |
896 | Int_t sec = 0; | |
897 | Int_t det = 0; | |
898 | Int_t qTot; | |
899 | ||
900 | Float_t hits[3]; | |
901 | Double_t eDep; | |
902 | ||
903 | Bool_t drRegion = kFALSE; | |
904 | Bool_t amRegion = kFALSE; | |
905 | ||
906 | TString cIdCurrent; | |
907 | TString cIdSensDr = "J"; | |
908 | TString cIdSensAm = "K"; | |
909 | Char_t cIdChamber[3]; | |
910 | cIdChamber[2] = 0; | |
911 | ||
912 | TLorentzVector pos, mom; | |
913 | ||
914 | const Int_t kNplan = AliTRDgeometry::Nplan(); | |
915 | const Int_t kNcham = AliTRDgeometry::Ncham(); | |
916 | const Int_t kNdetsec = kNplan * kNcham; | |
917 | ||
918 | const Double_t kBig = 1.0E+12; | |
919 | ||
bc327ce2 | 920 | const Float_t kWion = 23.53; // Ionization energy |
a328fff9 | 921 | const Float_t kEkinMinStep = 1.0e-5; // Minimum energy for the step size adjustment |
922 | ||
923 | // Set the maximum step size to a very large number for all | |
924 | // neutral particles and those outside the driftvolume | |
925 | gMC->SetMaxStep(kBig); | |
926 | ||
927 | // If not charged track or already stopped or disappeared, just return. | |
928 | if ((!gMC->TrackCharge()) || | |
929 | gMC->IsTrackStop() || | |
930 | gMC->IsTrackDisappeared()) return; | |
931 | ||
932 | // Inside a sensitive volume? | |
933 | cIdCurrent = gMC->CurrentVolName(); | |
934 | ||
935 | if (cIdSensDr == cIdCurrent[1]) drRegion = kTRUE; | |
936 | if (cIdSensAm == cIdCurrent[1]) amRegion = kTRUE; | |
937 | ||
938 | if ((!drRegion) && (!amRegion)) return; | |
939 | ||
940 | // The hit coordinates and charge | |
941 | gMC->TrackPosition(pos); | |
942 | hits[0] = pos[0]; | |
943 | hits[1] = pos[1]; | |
944 | hits[2] = pos[2]; | |
945 | ||
946 | // The sector number (0 - 17) | |
947 | // The numbering goes clockwise and starts at y = 0 | |
948 | Float_t phi = kRaddeg*TMath::ATan2(pos[0],pos[1]); | |
949 | if (phi < 90.) phi += 270.; | |
950 | else phi -= 90.; | |
951 | sec = ((Int_t) (phi / 20.)); | |
952 | ||
953 | // The plane and chamber number | |
954 | cIdChamber[0] = cIdCurrent[2]; | |
955 | cIdChamber[1] = cIdCurrent[3]; | |
956 | Int_t idChamber = (atoi(cIdChamber) % kNdetsec); | |
a5cadd36 | 957 | cha = kNcham - ((Int_t) idChamber / kNplan) - 1; |
a328fff9 | 958 | pla = ((Int_t) idChamber % kNplan); |
e0d47c25 | 959 | |
a328fff9 | 960 | // Check on selected volumes |
961 | Int_t addthishit = 1; | |
962 | if(fSensSelect) { | |
963 | if ((fSensPlane >= 0) && (pla != fSensPlane )) addthishit = 0; | |
964 | if ((fSensChamber >= 0) && (cha != fSensChamber)) addthishit = 0; | |
965 | if (fSensSector >= 0) { | |
966 | Int_t sens1 = fSensSector; | |
967 | Int_t sens2 = fSensSector + fSensSectorRange; | |
968 | sens2 -= ((Int_t) (sens2 / AliTRDgeometry::Nsect())) * AliTRDgeometry::Nsect(); | |
969 | if (sens1 < sens2) { | |
970 | if ((sec < sens1) || (sec >= sens2)) addthishit = 0; | |
971 | } | |
972 | else { | |
973 | if ((sec < sens1) && (sec >= sens2)) addthishit = 0; | |
974 | } | |
975 | } | |
976 | } | |
977 | ||
978 | if (!addthishit) return; | |
979 | ||
980 | det = fGeometry->GetDetector(pla,cha,sec); // The detector number | |
981 | ||
982 | Int_t trkStat = 0; // 0: InFlight 1:Entering 2:Exiting | |
983 | ||
984 | // Special hits only in the drift region | |
985 | if (drRegion) { | |
986 | ||
987 | // Create a track reference at the entrance and exit of each | |
988 | // chamber that contain the momentum components of the particle | |
989 | ||
990 | if (gMC->IsTrackEntering()) { | |
991 | gMC->TrackMomentum(mom); | |
992 | AddTrackReference(gAlice->GetMCApp()->GetCurrentTrackNumber()); | |
993 | trkStat = 1; | |
994 | } | |
995 | if (gMC->IsTrackExiting()) { | |
996 | gMC->TrackMomentum(mom); | |
997 | AddTrackReference(gAlice->GetMCApp()->GetCurrentTrackNumber()); | |
998 | trkStat = 2; | |
999 | } | |
1000 | ||
1001 | // Create the hits from TR photons | |
1002 | if (fTR) CreateTRhit(det); | |
1003 | ||
1004 | } | |
1005 | ||
1006 | // Calculate the charge according to GEANT Edep | |
1007 | // Create a new dEdx hit | |
1008 | eDep = TMath::Max(gMC->Edep(),0.0) * 1.0e+09; | |
1009 | qTot = (Int_t) (eDep / kWion); | |
c4214bc0 | 1010 | AddHit(gAlice->GetMCApp()->GetCurrentTrackNumber() |
1011 | ,det,hits,qTot,drRegion); | |
a328fff9 | 1012 | |
1013 | // Set Maximum Step Size | |
1014 | // Produce only one hit if Ekin is below cutoff | |
1015 | if ((gMC->Etot() - gMC->TrackMass()) < kEkinMinStep) return; | |
1016 | gMC->SetMaxStep(fStepSize); | |
1017 | ||
1018 | } | |
1019 | ||
5c7f4665 | 1020 | //_____________________________________________________________________________ |
1021 | Double_t AliTRDv1::BetheBloch(Double_t bg) | |
1022 | { | |
1023 | // | |
1024 | // Parametrization of the Bethe-Bloch-curve | |
1025 | // The parametrization is the same as for the TPC and is taken from Lehrhaus. | |
1026 | // | |
1027 | ||
1028 | // This parameters have been adjusted to averaged values from GEANT | |
1029 | const Double_t kP1 = 7.17960e-02; | |
1030 | const Double_t kP2 = 8.54196; | |
1031 | const Double_t kP3 = 1.38065e-06; | |
1032 | const Double_t kP4 = 5.30972; | |
1033 | const Double_t kP5 = 2.83798; | |
1034 | ||
1035 | // This parameters have been adjusted to Xe-data found in: | |
1036 | // Allison & Cobb, Ann. Rev. Nucl. Sci. (1980), 30, 253 | |
1037 | //const Double_t kP1 = 0.76176E-1; | |
1038 | //const Double_t kP2 = 10.632; | |
1039 | //const Double_t kP3 = 3.17983E-6; | |
1040 | //const Double_t kP4 = 1.8631; | |
1041 | //const Double_t kP5 = 1.9479; | |
1042 | ||
f73816f5 | 1043 | // Lower cutoff of the Bethe-Bloch-curve to limit step sizes |
1044 | const Double_t kBgMin = 0.8; | |
1045 | const Double_t kBBMax = 6.83298; | |
1046 | //const Double_t kBgMin = 0.6; | |
1047 | //const Double_t kBBMax = 17.2809; | |
1048 | //const Double_t kBgMin = 0.4; | |
1049 | //const Double_t kBBMax = 82.0; | |
1050 | ||
1051 | if (bg > kBgMin) { | |
5c7f4665 | 1052 | Double_t yy = bg / TMath::Sqrt(1. + bg*bg); |
1053 | Double_t aa = TMath::Power(yy,kP4); | |
1054 | Double_t bb = TMath::Power((1./bg),kP5); | |
1055 | bb = TMath::Log(kP3 + bb); | |
1056 | return ((kP2 - aa - bb)*kP1 / aa); | |
1057 | } | |
f73816f5 | 1058 | else { |
1059 | return kBBMax; | |
1060 | } | |
d3f347ff | 1061 | |
fe4da5cc | 1062 | } |
5c7f4665 | 1063 | |
a328fff9 | 1064 | //_____________________________________________________________________________ |
c4214bc0 | 1065 | Double_t AliTRDv1::BetheBlochGeant(Double_t bg) |
a328fff9 | 1066 | { |
1067 | // | |
1068 | // Return dN/dx (number of primary collisions per centimeter) | |
1069 | // for given beta*gamma factor. | |
1070 | // | |
1071 | // Implemented by K.Oyama according to GEANT 3 parametrization shown in | |
1072 | // A.Andronic's webpage: http://www-alice.gsi.de/trd/papers/dedx/dedx.html | |
1073 | // This must be used as a set with IntSpecGeant. | |
1074 | // | |
1075 | ||
1076 | Double_t arr_g[20] = { | |
1077 | 1.100000, 1.200000, 1.300000, 1.500000, | |
1078 | 1.800000, 2.000000, 2.500000, 3.000000, | |
1079 | 4.000000, 7.000000, 10.000000, 20.000000, | |
1080 | 40.000000, 70.000000, 100.000000, 300.000000, | |
1081 | 600.000000, 1000.000000, 3000.000000, 10000.000000 }; | |
1082 | ||
1083 | Double_t arr_nc[20] = { | |
1084 | 75.009056, 45.508083, 35.299252, 27.116327, | |
1085 | 22.734999, 21.411915, 19.934095, 19.449375, | |
1086 | 19.344431, 20.185553, 21.027925, 22.912676, | |
1087 | 24.933352, 26.504053, 27.387468, 29.566597, | |
1088 | 30.353779, 30.787134, 31.129285, 31.157350 }; | |
1089 | ||
1090 | // betagamma to gamma | |
1091 | Double_t g = TMath::Sqrt( 1. + bg*bg ); | |
1092 | ||
1093 | // Find the index just before the point we need. | |
1094 | int i; | |
1095 | for( i = 0 ; i < 18 ; i++ ) | |
1096 | if( arr_g[i] < g && arr_g[i+1] > g ) | |
1097 | break; | |
1098 | ||
1099 | // Simple interpolation. | |
1100 | Double_t pp = ((arr_nc[i+1] - arr_nc[i]) / | |
1101 | (arr_g[i+1]-arr_g[i])) * (g-arr_g[i]) + arr_nc[i]; | |
1102 | ||
c4214bc0 | 1103 | return pp; //arr_nc[8]; |
a328fff9 | 1104 | |
1105 | } | |
1106 | ||
c4214bc0 | 1107 | //_____________________________________________________________________________ |
1108 | void AliTRDv1::Stepping() | |
1109 | { | |
1110 | // Stepping info | |
1111 | // --- | |
1112 | ||
1113 | cout << "X(cm) " | |
1114 | << "Y(cm) " | |
1115 | << "Z(cm) " | |
1116 | << "KinE(MeV) " | |
1117 | << "dE(MeV) " | |
1118 | << "Step(cm) " | |
1119 | << "TrackL(cm) " | |
1120 | << "Volume " | |
1121 | << "Process " | |
1122 | << endl; | |
1123 | ||
1124 | // Position | |
1125 | // | |
1126 | Double_t x, y, z; | |
1127 | gMC->TrackPosition(x, y, z); | |
1128 | cout << setw(8) << setprecision(3) << x << " " | |
1129 | << setw(8) << setprecision(3) << y << " " | |
1130 | << setw(8) << setprecision(3) << z << " "; | |
1131 | ||
1132 | // Kinetic energy | |
1133 | // | |
1134 | Double_t px, py, pz, etot; | |
1135 | gMC->TrackMomentum(px, py, pz, etot); | |
1136 | Double_t ekin = etot - gMC->TrackMass(); | |
1137 | cout << setw(9) << setprecision(4) << ekin*1e03 << " "; | |
1138 | ||
1139 | // Energy deposit | |
1140 | // | |
1141 | cout << setw(9) << setprecision(4) << gMC->Edep()*1e03 << " "; | |
1142 | ||
1143 | // Step length | |
1144 | // | |
1145 | cout << setw(8) << setprecision(3) << gMC->TrackStep() << " "; | |
1146 | ||
1147 | // Track length | |
1148 | // | |
1149 | cout << setw(8) << setprecision(3) << gMC->TrackLength() << " "; | |
1150 | ||
1151 | // Volume | |
1152 | // | |
1153 | if (gMC->CurrentVolName() != 0) | |
1154 | cout << setw(4) << gMC->CurrentVolName() << " "; | |
1155 | else | |
1156 | cout << setw(4) << "None" << " "; | |
1157 | ||
1158 | // Process | |
1159 | // | |
1160 | TArrayI processes; | |
1161 | Int_t nofProcesses = gMC->StepProcesses(processes); | |
1162 | for(int ip=0;ip<nofProcesses; ip++) | |
1163 | cout << TMCProcessName[processes[ip]]<<" / "; | |
1164 | ||
1165 | cout << endl; | |
1166 | } | |
1167 | ||
1168 | ||
5c7f4665 | 1169 | //_____________________________________________________________________________ |
1170 | Double_t Ermilova(Double_t *x, Double_t *) | |
1171 | { | |
1172 | // | |
1173 | // Calculates the delta-ray energy distribution according to Ermilova. | |
1174 | // Logarithmic scale ! | |
1175 | // | |
1176 | ||
1177 | Double_t energy; | |
1178 | Double_t dpos; | |
1179 | Double_t dnde; | |
1180 | ||
1181 | Int_t pos1, pos2; | |
1182 | ||
8230f242 | 1183 | const Int_t kNv = 31; |
5c7f4665 | 1184 | |
8230f242 | 1185 | Float_t vxe[kNv] = { 2.3026, 2.9957, 3.4012, 3.6889, 3.9120 |
1186 | , 4.0943, 4.2485, 4.3820, 4.4998, 4.6052 | |
1187 | , 4.7005, 5.0752, 5.2983, 5.7038, 5.9915 | |
1188 | , 6.2146, 6.5221, 6.9078, 7.3132, 7.6009 | |
1189 | , 8.0064, 8.5172, 8.6995, 8.9872, 9.2103 | |
1190 | , 9.4727, 9.9035,10.3735,10.5966,10.8198 | |
1191 | ,11.5129 }; | |
5c7f4665 | 1192 | |
8230f242 | 1193 | Float_t vye[kNv] = { 80.0 , 31.0 , 23.3 , 21.1 , 21.0 |
1194 | , 20.9 , 20.8 , 20.0 , 16.0 , 11.0 | |
1195 | , 8.0 , 6.0 , 5.2 , 4.6 , 4.0 | |
1196 | , 3.5 , 3.0 , 1.4 , 0.67 , 0.44 | |
1197 | , 0.3 , 0.18 , 0.12 , 0.08 , 0.056 | |
1198 | , 0.04 , 0.023, 0.015, 0.011, 0.01 | |
1199 | , 0.004 }; | |
5c7f4665 | 1200 | |
1201 | energy = x[0]; | |
1202 | ||
1203 | // Find the position | |
1204 | pos1 = pos2 = 0; | |
1205 | dpos = 0; | |
1206 | do { | |
1207 | dpos = energy - vxe[pos2++]; | |
1208 | } | |
1209 | while (dpos > 0); | |
1210 | pos2--; | |
f73816f5 | 1211 | if (pos2 > kNv) pos2 = kNv - 1; |
5c7f4665 | 1212 | pos1 = pos2 - 1; |
1213 | ||
1214 | // Differentiate between the sampling points | |
1215 | dnde = (vye[pos1] - vye[pos2]) / (vxe[pos2] - vxe[pos1]); | |
1216 | ||
1217 | return dnde; | |
1218 | ||
1219 | } | |
a328fff9 | 1220 | |
1221 | //_____________________________________________________________________________ | |
1222 | Double_t IntSpecGeant(Double_t *x, Double_t *) | |
1223 | { | |
1224 | // | |
1225 | // Integrated spectrum from Geant3 | |
1226 | // | |
1227 | ||
96efaf83 | 1228 | const Int_t npts = 83; |
1229 | Double_t arre[npts] = { | |
a328fff9 | 1230 | 2.421257, 2.483278, 2.534301, 2.592230, |
1231 | 2.672067, 2.813299, 3.015059, 3.216819, | |
1232 | 3.418579, 3.620338, 3.868209, 3.920198, | |
1233 | 3.978284, 4.063923, 4.186264, 4.308605, | |
1234 | 4.430946, 4.553288, 4.724261, 4.837736, | |
1235 | 4.999842, 5.161949, 5.324056, 5.486163, | |
1236 | 5.679688, 5.752998, 5.857728, 5.962457, | |
1237 | 6.067185, 6.171914, 6.315653, 6.393674, | |
1238 | 6.471694, 6.539689, 6.597658, 6.655627, | |
1239 | 6.710957, 6.763648, 6.816338, 6.876198, | |
1240 | 6.943227, 7.010257, 7.106285, 7.252151, | |
1241 | 7.460531, 7.668911, 7.877290, 8.085670, | |
1242 | 8.302979, 8.353585, 8.413120, 8.483500, | |
1243 | 8.541030, 8.592857, 8.668865, 8.820485, | |
1244 | 9.037086, 9.253686, 9.470286, 9.686887, | |
1245 | 9.930838, 9.994655, 10.085822, 10.176990, | |
1246 | 10.268158, 10.359325, 10.503614, 10.627565, | |
1247 | 10.804637, 10.981709, 11.158781, 11.335854, | |
1248 | 11.593397, 11.781165, 12.049404, 12.317644, | |
1249 | 12.585884, 12.854123, 14.278421, 16.975889, | |
1250 | 20.829416, 24.682943, 28.536469 | |
1251 | }; | |
96efaf83 | 1252 | /* |
1253 | Double_t arrdndx[npts] = { | |
a328fff9 | 1254 | 19.344431, 18.664679, 18.136106, 17.567745, |
1255 | 16.836426, 15.677382, 14.281277, 13.140237, | |
1256 | 12.207677, 11.445510, 10.697049, 10.562296, | |
1257 | 10.414673, 10.182341, 9.775256, 9.172330, | |
1258 | 8.240271, 6.898587, 4.808303, 3.889751, | |
1259 | 3.345288, 3.093431, 2.897347, 2.692470, | |
1260 | 2.436222, 2.340029, 2.208579, 2.086489, | |
1261 | 1.975535, 1.876519, 1.759626, 1.705024, | |
1262 | 1.656374, 1.502638, 1.330566, 1.200697, | |
1263 | 1.101168, 1.019323, 0.943867, 0.851951, | |
1264 | 0.755229, 0.671576, 0.570675, 0.449672, | |
1265 | 0.326722, 0.244225, 0.188225, 0.149608, | |
1266 | 0.121529, 0.116289, 0.110636, 0.103490, | |
1267 | 0.096147, 0.089191, 0.079780, 0.063927, | |
1268 | 0.047642, 0.036341, 0.028250, 0.022285, | |
1269 | 0.017291, 0.016211, 0.014802, 0.013533, | |
1270 | 0.012388, 0.011352, 0.009803, 0.008537, | |
1271 | 0.007039, 0.005829, 0.004843, 0.004034, | |
1272 | 0.003101, 0.002564, 0.001956, 0.001494, | |
1273 | 0.001142, 0.000873, 0.000210, 0.000014, | |
1274 | 0.000000, 0.000000, 0.000000 | |
1275 | }; | |
96efaf83 | 1276 | */ |
1277 | // Differentiate | |
1278 | // dnde = (arrdndx[i-1] - arrdndx[i]) / (arre[i] - arre[i-1]); | |
1279 | ||
1280 | Double_t arrdnde[npts] = { | |
1281 | 10.960000, 10.960000, 10.359500, 9.811340, | |
1282 | 9.1601500, 8.206670, 6.919630, 5.655430, | |
1283 | 4.6221300, 3.777610, 3.019560, 2.591950, | |
1284 | 2.5414600, 2.712920, 3.327460, 4.928240, | |
1285 | 7.6185300, 10.966700, 12.225800, 8.094750, | |
1286 | 3.3586900, 1.553650, 1.209600, 1.263840, | |
1287 | 1.3241100, 1.312140, 1.255130, 1.165770, | |
1288 | 1.0594500, 0.945450, 0.813231, 0.699837, | |
1289 | 0.6235580, 2.260990, 2.968350, 2.240320, | |
1290 | 1.7988300, 1.553300, 1.432070, 1.535520, | |
1291 | 1.4429900, 1.247990, 1.050750, 0.829549, | |
1292 | 0.5900280, 0.395897, 0.268741, 0.185320, | |
1293 | 0.1292120, 0.103545, 0.0949525, 0.101535, | |
1294 | 0.1276380, 0.134216, 0.123816, 0.104557, | |
1295 | 0.0751843, 0.0521745, 0.0373546, 0.0275391, | |
1296 | 0.0204713, 0.0169234, 0.0154552, 0.0139194, | |
1297 | 0.0125592, 0.0113638, 0.0107354, 0.0102137, | |
1298 | 0.00845984, 0.00683338, 0.00556836, 0.00456874, | |
1299 | 0.0036227, 0.00285991, 0.00226664, 0.00172234, | |
1300 | 0.00131226, 0.00100284, 0.000465492, 7.26607e-05, | |
1301 | 3.63304e-06, 0.0000000, 0.0000000 | |
1302 | }; | |
a328fff9 | 1303 | |
1304 | Int_t i; | |
1305 | Double_t energy = x[0]; | |
a328fff9 | 1306 | |
96efaf83 | 1307 | for( i = 0 ; i < npts ; i++ ) |
1308 | if( energy < arre[i] ) break; | |
a328fff9 | 1309 | |
1310 | if( i == 0 ) | |
45160b1f | 1311 | AliErrorGeneral("AliTRDv1","Given energy value is too small or zero"); |
a328fff9 | 1312 | |
96efaf83 | 1313 | return arrdnde[i]; |
a328fff9 | 1314 | |
1315 | } |