]>
Commit | Line | Data |
---|---|---|
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 | ||
16 | /* | |
17 | $Log$ | |
9d0b222b | 18 | Revision 1.18 2000/05/08 16:17:27 cblume |
19 | Merge TRD-develop | |
20 | ||
6f1e466d | 21 | Revision 1.17.2.1 2000/05/08 14:59:16 cblume |
22 | Made inline function non-virtual. Bug fix in setting sensitive chamber | |
23 | ||
24 | Revision 1.17 2000/02/28 19:10:26 cblume | |
25 | Include the new TRD classes | |
26 | ||
851d3db9 | 27 | Revision 1.16.4.1 2000/02/28 18:04:35 cblume |
28 | Change to new hit version, introduce geometry class, and move digitization and clustering to AliTRDdigitizer/AliTRDclusterizerV1 | |
29 | ||
30 | Revision 1.16 1999/11/05 22:50:28 fca | |
31 | Do not use Atan, removed from ROOT too | |
32 | ||
90f8d287 | 33 | Revision 1.15 1999/11/02 17:20:19 fca |
34 | initialise nbytes before using it | |
35 | ||
036da493 | 36 | Revision 1.14 1999/11/02 17:15:54 fca |
37 | Correct ansi scoping not accepted by HP compilers | |
38 | ||
0549c011 | 39 | Revision 1.13 1999/11/02 17:14:51 fca |
40 | Correct ansi scoping not accepted by HP compilers | |
41 | ||
9c767df4 | 42 | Revision 1.12 1999/11/02 16:35:56 fca |
43 | New version of TRD introduced | |
44 | ||
5c7f4665 | 45 | Revision 1.11 1999/11/01 20:41:51 fca |
46 | Added protections against using the wrong version of FRAME | |
47 | ||
ab76897d | 48 | Revision 1.10 1999/09/29 09:24:35 fca |
49 | Introduction of the Copyright and cvs Log | |
50 | ||
4c039060 | 51 | */ |
52 | ||
fe4da5cc | 53 | /////////////////////////////////////////////////////////////////////////////// |
54 | // // | |
5c7f4665 | 55 | // Transition Radiation Detector version 2 -- slow simulator // |
fe4da5cc | 56 | // // |
57 | //Begin_Html | |
58 | /* | |
5c7f4665 | 59 | <img src="picts/AliTRDfullClass.gif"> |
fe4da5cc | 60 | */ |
61 | //End_Html | |
62 | // // | |
63 | // // | |
64 | /////////////////////////////////////////////////////////////////////////////// | |
65 | ||
66 | #include <TMath.h> | |
fe4da5cc | 67 | #include <TVector.h> |
5c7f4665 | 68 | #include <TRandom.h> |
fe4da5cc | 69 | |
fe4da5cc | 70 | #include "AliRun.h" |
fe4da5cc | 71 | #include "AliMC.h" |
d3f347ff | 72 | #include "AliConst.h" |
5c7f4665 | 73 | |
851d3db9 | 74 | #include "AliTRDv1.h" |
75 | #include "AliTRDmatrix.h" | |
76 | #include "AliTRDgeometry.h" | |
77 | ||
fe4da5cc | 78 | ClassImp(AliTRDv1) |
79 | ||
80 | //_____________________________________________________________________________ | |
81 | AliTRDv1::AliTRDv1(const char *name, const char *title) | |
82 | :AliTRD(name, title) | |
83 | { | |
84 | // | |
851d3db9 | 85 | // Standard constructor for Transition Radiation Detector version 1 |
fe4da5cc | 86 | // |
82bbf98a | 87 | |
9d0b222b | 88 | fIdSens = 0; |
82bbf98a | 89 | |
9d0b222b | 90 | fIdChamber1 = 0; |
91 | fIdChamber2 = 0; | |
92 | fIdChamber3 = 0; | |
5c7f4665 | 93 | |
9d0b222b | 94 | fSensSelect = 0; |
95 | fSensPlane = -1; | |
96 | fSensChamber = -1; | |
97 | fSensSector = -1; | |
98 | fSensSectorRange = 0; | |
5c7f4665 | 99 | |
9d0b222b | 100 | fDeltaE = NULL; |
5c7f4665 | 101 | |
102 | SetBufferSize(128000); | |
103 | ||
104 | } | |
105 | ||
106 | //_____________________________________________________________________________ | |
107 | AliTRDv1::~AliTRDv1() | |
108 | { | |
82bbf98a | 109 | |
5c7f4665 | 110 | if (fDeltaE) delete fDeltaE; |
82bbf98a | 111 | |
fe4da5cc | 112 | } |
113 | ||
114 | //_____________________________________________________________________________ | |
115 | void AliTRDv1::CreateGeometry() | |
116 | { | |
117 | // | |
851d3db9 | 118 | // Create the GEANT geometry for the Transition Radiation Detector - Version 1 |
5c7f4665 | 119 | // This version covers the full azimuth. |
d3f347ff | 120 | // |
121 | ||
82bbf98a | 122 | // Check that FRAME is there otherwise we have no place where to put the TRD |
123 | AliModule* FRAME = gAlice->GetModule("FRAME"); | |
124 | if (!FRAME) return; | |
d3f347ff | 125 | |
82bbf98a | 126 | // Define the chambers |
127 | AliTRD::CreateGeometry(); | |
d3f347ff | 128 | |
fe4da5cc | 129 | } |
130 | ||
131 | //_____________________________________________________________________________ | |
132 | void AliTRDv1::CreateMaterials() | |
133 | { | |
134 | // | |
851d3db9 | 135 | // Create materials for the Transition Radiation Detector version 1 |
fe4da5cc | 136 | // |
82bbf98a | 137 | |
d3f347ff | 138 | AliTRD::CreateMaterials(); |
82bbf98a | 139 | |
fe4da5cc | 140 | } |
141 | ||
5c7f4665 | 142 | //_____________________________________________________________________________ |
143 | void AliTRDv1::Init() | |
144 | { | |
145 | // | |
146 | // Initialise Transition Radiation Detector after geometry has been built. | |
5c7f4665 | 147 | // |
148 | ||
149 | AliTRD::Init(); | |
150 | ||
851d3db9 | 151 | printf(" Slow simulator\n\n"); |
152 | if (fSensSelect) { | |
153 | if (fSensPlane >= 0) | |
154 | printf(" Only plane %d is sensitive\n",fSensPlane); | |
155 | if (fSensChamber >= 0) | |
156 | printf(" Only chamber %d is sensitive\n",fSensChamber); | |
9d0b222b | 157 | if (fSensSector >= 0) { |
158 | Int_t sens1 = fSensSector; | |
159 | Int_t sens2 = fSensSector + fSensSectorRange; | |
160 | sens2 -= ((Int_t) (sens2 / kNsect)) * kNsect; | |
161 | printf(" Only sectors %d - %d are sensitive\n",sens1,sens2-1); | |
162 | } | |
851d3db9 | 163 | } |
164 | printf("\n"); | |
5c7f4665 | 165 | |
166 | // First ionization potential (eV) for the gas mixture (90% Xe + 10% CO2) | |
167 | const Float_t kPoti = 12.1; | |
168 | // Maximum energy (50 keV); | |
169 | const Float_t kEend = 50000.0; | |
170 | // Ermilova distribution for the delta-ray spectrum | |
171 | Float_t Poti = TMath::Log(kPoti); | |
172 | Float_t Eend = TMath::Log(kEend); | |
173 | fDeltaE = new TF1("deltae",Ermilova,Poti,Eend,0); | |
174 | ||
175 | // Identifier of the sensitive volume (drift region) | |
176 | fIdSens = gMC->VolId("UL05"); | |
82bbf98a | 177 | |
178 | // Identifier of the TRD-driftchambers | |
179 | fIdChamber1 = gMC->VolId("UCIO"); | |
180 | fIdChamber2 = gMC->VolId("UCIM"); | |
181 | fIdChamber3 = gMC->VolId("UCII"); | |
182 | ||
5c7f4665 | 183 | for (Int_t i = 0; i < 80; i++) printf("*"); |
184 | printf("\n"); | |
185 | ||
fe4da5cc | 186 | } |
187 | ||
5c7f4665 | 188 | //_____________________________________________________________________________ |
189 | void AliTRDv1::SetSensPlane(Int_t iplane) | |
190 | { | |
191 | // | |
851d3db9 | 192 | // Defines the hit-sensitive plane (0-5) |
5c7f4665 | 193 | // |
82bbf98a | 194 | |
851d3db9 | 195 | if ((iplane < 0) || (iplane > 5)) { |
5c7f4665 | 196 | printf("Wrong input value: %d\n",iplane); |
197 | printf("Use standard setting\n"); | |
851d3db9 | 198 | fSensPlane = -1; |
199 | fSensSelect = 0; | |
5c7f4665 | 200 | return; |
201 | } | |
82bbf98a | 202 | |
5c7f4665 | 203 | fSensSelect = 1; |
204 | fSensPlane = iplane; | |
82bbf98a | 205 | |
5c7f4665 | 206 | } |
207 | ||
208 | //_____________________________________________________________________________ | |
209 | void AliTRDv1::SetSensChamber(Int_t ichamber) | |
210 | { | |
211 | // | |
851d3db9 | 212 | // Defines the hit-sensitive chamber (0-4) |
5c7f4665 | 213 | // |
214 | ||
851d3db9 | 215 | if ((ichamber < 0) || (ichamber > 4)) { |
5c7f4665 | 216 | printf("Wrong input value: %d\n",ichamber); |
217 | printf("Use standard setting\n"); | |
851d3db9 | 218 | fSensChamber = -1; |
219 | fSensSelect = 0; | |
5c7f4665 | 220 | return; |
221 | } | |
222 | ||
223 | fSensSelect = 1; | |
224 | fSensChamber = ichamber; | |
225 | ||
226 | } | |
227 | ||
228 | //_____________________________________________________________________________ | |
229 | void AliTRDv1::SetSensSector(Int_t isector) | |
230 | { | |
231 | // | |
851d3db9 | 232 | // Defines the hit-sensitive sector (0-17) |
5c7f4665 | 233 | // |
234 | ||
9d0b222b | 235 | SetSensSector(isector,1); |
236 | ||
237 | } | |
238 | ||
239 | //_____________________________________________________________________________ | |
240 | void AliTRDv1::SetSensSector(Int_t isector, Int_t nsector) | |
241 | { | |
242 | // | |
243 | // Defines a range of hit-sensitive sectors. The range is defined by | |
244 | // <isector> (0-17) as the starting point and <nsector> as the number | |
245 | // of sectors to be included. | |
246 | // | |
247 | ||
851d3db9 | 248 | if ((isector < 0) || (isector > 17)) { |
9d0b222b | 249 | printf("Wrong input value <isector>: %d\n",isector); |
5c7f4665 | 250 | printf("Use standard setting\n"); |
9d0b222b | 251 | fSensSector = -1; |
252 | fSensSectorRange = 0; | |
253 | fSensSelect = 0; | |
5c7f4665 | 254 | return; |
255 | } | |
256 | ||
9d0b222b | 257 | if ((nsector < 1) || (nsector > 18)) { |
258 | printf("Wrong input value <nsector>: %d\n",nsector); | |
259 | printf("Use standard setting\n"); | |
260 | fSensSector = -1; | |
261 | fSensSectorRange = 0; | |
262 | fSensSelect = 0; | |
263 | return; | |
264 | } | |
265 | ||
266 | fSensSelect = 1; | |
267 | fSensSector = isector; | |
268 | fSensSectorRange = nsector; | |
5c7f4665 | 269 | |
270 | } | |
271 | ||
272 | //_____________________________________________________________________________ | |
273 | void AliTRDv1::StepManager() | |
274 | { | |
275 | // | |
5c7f4665 | 276 | // Slow simulator. Every charged track produces electron cluster as hits |
277 | // along its path across the drift volume. The step size is set acording | |
278 | // to Bethe-Bloch. The energy distribution of the delta electrons follows | |
279 | // a spectrum taken from Ermilova et al. | |
280 | // | |
281 | ||
282 | Int_t iIdSens, icSens; | |
283 | Int_t iIdSpace, icSpace; | |
284 | Int_t iIdChamber, icChamber; | |
851d3db9 | 285 | Int_t pla = 0; |
286 | Int_t cha = 0; | |
287 | Int_t sec = 0; | |
288 | Int_t iPdg; | |
5c7f4665 | 289 | |
9d0b222b | 290 | Int_t det[1]; |
291 | ||
5c7f4665 | 292 | Float_t hits[4]; |
293 | Float_t random[1]; | |
294 | Float_t charge; | |
295 | Float_t aMass; | |
296 | ||
297 | Double_t pTot; | |
298 | Double_t qTot; | |
299 | Double_t eDelta; | |
300 | Double_t betaGamma, pp; | |
301 | ||
302 | TLorentzVector pos, mom; | |
82bbf98a | 303 | TClonesArray &lhits = *fHits; |
304 | ||
851d3db9 | 305 | const Double_t kBig = 1.0E+12; |
5c7f4665 | 306 | |
307 | // Ionization energy | |
851d3db9 | 308 | const Float_t kWion = 22.04; |
5c7f4665 | 309 | // Maximum energy for e+ e- g for the step-size calculation |
851d3db9 | 310 | const Float_t kPTotMax = 0.002; |
5c7f4665 | 311 | // Plateau value of the energy-loss for electron in xenon |
312 | // taken from: Allison + Comb, Ann. Rev. Nucl. Sci. (1980), 30, 253 | |
313 | //const Double_t kPlateau = 1.70; | |
314 | // the averaged value (26/3/99) | |
851d3db9 | 315 | const Float_t kPlateau = 1.55; |
5c7f4665 | 316 | // dN1/dx|min for the gas mixture (90% Xe + 10% CO2) |
851d3db9 | 317 | const Float_t kPrim = 48.0; |
5c7f4665 | 318 | // First ionization potential (eV) for the gas mixture (90% Xe + 10% CO2) |
851d3db9 | 319 | const Float_t kPoti = 12.1; |
320 | ||
321 | // PDG code electron | |
322 | const Int_t pdgElectron = 11; | |
5c7f4665 | 323 | |
324 | // Set the maximum step size to a very large number for all | |
325 | // neutral particles and those outside the driftvolume | |
326 | gMC->SetMaxStep(kBig); | |
327 | ||
328 | // Use only charged tracks | |
329 | if (( gMC->TrackCharge() ) && | |
330 | (!gMC->IsTrackStop() ) && | |
331 | (!gMC->IsTrackDisappeared())) { | |
fe4da5cc | 332 | |
5c7f4665 | 333 | // Inside a sensitive volume? |
82bbf98a | 334 | iIdSens = gMC->CurrentVolID(icSens); |
335 | if (iIdSens == fIdSens) { | |
336 | ||
82bbf98a | 337 | iIdSpace = gMC->CurrentVolOffID(4,icSpace ); |
338 | iIdChamber = gMC->CurrentVolOffID(1,icChamber); | |
fe4da5cc | 339 | |
5c7f4665 | 340 | // Calculate the energy of the delta-electrons |
341 | eDelta = TMath::Exp(fDeltaE->GetRandom()) - kPoti; | |
342 | eDelta = TMath::Max(eDelta,0.0); | |
343 | ||
344 | // The number of secondary electrons created | |
345 | qTot = (Double_t) ((Int_t) (eDelta / kWion) + 1); | |
346 | ||
347 | // The hit coordinates and charge | |
348 | gMC->TrackPosition(pos); | |
349 | hits[0] = pos[0]; | |
350 | hits[1] = pos[1]; | |
351 | hits[2] = pos[2]; | |
352 | hits[3] = qTot; | |
353 | ||
851d3db9 | 354 | // The sector number (0 - 17) |
355 | // The numbering goes clockwise and starts at y = 0 | |
356 | Float_t phi = kRaddeg*TMath::ATan2(pos[0],pos[1]); | |
357 | if (phi < 90.) | |
358 | phi = phi + 270.; | |
359 | else | |
360 | phi = phi - 90.; | |
361 | sec = ((Int_t) (phi / 20)); | |
82bbf98a | 362 | |
d3f347ff | 363 | // The chamber number |
851d3db9 | 364 | // 0: outer left |
365 | // 1: middle left | |
366 | // 2: inner | |
367 | // 3: middle right | |
368 | // 4: outer right | |
82bbf98a | 369 | if (iIdChamber == fIdChamber1) |
851d3db9 | 370 | cha = (hits[2] < 0 ? 0 : 4); |
82bbf98a | 371 | else if (iIdChamber == fIdChamber2) |
851d3db9 | 372 | cha = (hits[2] < 0 ? 1 : 3); |
82bbf98a | 373 | else if (iIdChamber == fIdChamber3) |
851d3db9 | 374 | cha = 2; |
82bbf98a | 375 | |
fe4da5cc | 376 | // The plane number |
851d3db9 | 377 | // The numbering starts at the innermost plane |
378 | pla = icChamber - TMath::Nint((Float_t) (icChamber / 7)) * 6 - 1; | |
82bbf98a | 379 | |
5c7f4665 | 380 | // Check on selected volumes |
381 | Int_t addthishit = 1; | |
382 | if (fSensSelect) { | |
6f1e466d | 383 | if ((fSensPlane >= 0) && (pla != fSensPlane )) addthishit = 0; |
384 | if ((fSensChamber >= 0) && (cha != fSensChamber)) addthishit = 0; | |
9d0b222b | 385 | if (fSensSector >= 0) { |
386 | Int_t sens1 = fSensSector; | |
387 | Int_t sens2 = fSensSector + fSensSectorRange; | |
388 | sens2 -= ((Int_t) (sens2 / kNsect)) * kNsect; | |
389 | if (sens1 < sens2) { | |
390 | if ((sec < sens1) || (sec >= sens2)) addthishit = 0; | |
391 | } | |
392 | else { | |
393 | if ((sec < sens1) && (sec >= sens2)) addthishit = 0; | |
394 | } | |
395 | } | |
5c7f4665 | 396 | } |
397 | ||
398 | // Add this hit | |
399 | if (addthishit) { | |
400 | ||
9d0b222b | 401 | det[0] = fGeometry->GetDetector(pla,cha,sec); |
851d3db9 | 402 | new(lhits[fNhits++]) AliTRDhit(fIshunt |
403 | ,gAlice->CurrentTrack() | |
9d0b222b | 404 | ,det |
851d3db9 | 405 | ,hits); |
5c7f4665 | 406 | |
407 | // The energy loss according to Bethe Bloch | |
408 | gMC->TrackMomentum(mom); | |
409 | pTot = mom.Rho(); | |
851d3db9 | 410 | iPdg = TMath::Abs(gMC->TrackPid()); |
411 | if ( (iPdg != pdgElectron) || | |
412 | ((iPdg == pdgElectron) && (pTot < kPTotMax))) { | |
5c7f4665 | 413 | aMass = gMC->TrackMass(); |
414 | betaGamma = pTot / aMass; | |
415 | pp = kPrim * BetheBloch(betaGamma); | |
416 | // Take charge > 1 into account | |
417 | charge = gMC->TrackCharge(); | |
418 | if (TMath::Abs(charge) > 1) pp = pp * charge*charge; | |
419 | } | |
420 | // Electrons above 20 Mev/c are at the plateau | |
421 | else { | |
422 | pp = kPrim * kPlateau; | |
423 | } | |
424 | ||
425 | // Calculate the maximum step size for the next tracking step | |
426 | if (pp > 0) { | |
427 | do | |
428 | gMC->Rndm(random,1); | |
429 | while ((random[0] == 1.) || (random[0] == 0.)); | |
430 | gMC->SetMaxStep( - TMath::Log(random[0]) / pp); | |
431 | } | |
432 | ||
433 | } | |
434 | else { | |
435 | // set step size to maximal value | |
436 | gMC->SetMaxStep(kBig); | |
437 | } | |
d3f347ff | 438 | |
439 | } | |
440 | ||
5c7f4665 | 441 | } |
442 | ||
443 | } | |
444 | ||
445 | //_____________________________________________________________________________ | |
446 | Double_t AliTRDv1::BetheBloch(Double_t bg) | |
447 | { | |
448 | // | |
449 | // Parametrization of the Bethe-Bloch-curve | |
450 | // The parametrization is the same as for the TPC and is taken from Lehrhaus. | |
451 | // | |
452 | ||
453 | // This parameters have been adjusted to averaged values from GEANT | |
454 | const Double_t kP1 = 7.17960e-02; | |
455 | const Double_t kP2 = 8.54196; | |
456 | const Double_t kP3 = 1.38065e-06; | |
457 | const Double_t kP4 = 5.30972; | |
458 | const Double_t kP5 = 2.83798; | |
459 | ||
460 | // This parameters have been adjusted to Xe-data found in: | |
461 | // Allison & Cobb, Ann. Rev. Nucl. Sci. (1980), 30, 253 | |
462 | //const Double_t kP1 = 0.76176E-1; | |
463 | //const Double_t kP2 = 10.632; | |
464 | //const Double_t kP3 = 3.17983E-6; | |
465 | //const Double_t kP4 = 1.8631; | |
466 | //const Double_t kP5 = 1.9479; | |
467 | ||
468 | if (bg > 0) { | |
469 | Double_t yy = bg / TMath::Sqrt(1. + bg*bg); | |
470 | Double_t aa = TMath::Power(yy,kP4); | |
471 | Double_t bb = TMath::Power((1./bg),kP5); | |
472 | bb = TMath::Log(kP3 + bb); | |
473 | return ((kP2 - aa - bb)*kP1 / aa); | |
474 | } | |
475 | else | |
476 | return 0; | |
d3f347ff | 477 | |
fe4da5cc | 478 | } |
5c7f4665 | 479 | |
480 | //_____________________________________________________________________________ | |
481 | Double_t Ermilova(Double_t *x, Double_t *) | |
482 | { | |
483 | // | |
484 | // Calculates the delta-ray energy distribution according to Ermilova. | |
485 | // Logarithmic scale ! | |
486 | // | |
487 | ||
488 | Double_t energy; | |
489 | Double_t dpos; | |
490 | Double_t dnde; | |
491 | ||
492 | Int_t pos1, pos2; | |
493 | ||
494 | const Int_t nV = 31; | |
495 | ||
496 | Float_t vxe[nV] = { 2.3026, 2.9957, 3.4012, 3.6889, 3.9120 | |
497 | , 4.0943, 4.2485, 4.3820, 4.4998, 4.6052 | |
498 | , 4.7005, 5.0752, 5.2983, 5.7038, 5.9915 | |
499 | , 6.2146, 6.5221, 6.9078, 7.3132, 7.6009 | |
500 | , 8.0064, 8.5172, 8.6995, 8.9872, 9.2103 | |
501 | , 9.4727, 9.9035,10.3735,10.5966,10.8198 | |
502 | ,11.5129 }; | |
503 | ||
504 | Float_t vye[nV] = { 80.0 , 31.0 , 23.3 , 21.1 , 21.0 | |
505 | , 20.9 , 20.8 , 20.0 , 16.0 , 11.0 | |
506 | , 8.0 , 6.0 , 5.2 , 4.6 , 4.0 | |
507 | , 3.5 , 3.0 , 1.4 , 0.67 , 0.44 | |
508 | , 0.3 , 0.18 , 0.12 , 0.08 , 0.056 | |
509 | , 0.04 , 0.023, 0.015, 0.011, 0.01 | |
510 | , 0.004 }; | |
511 | ||
512 | energy = x[0]; | |
513 | ||
514 | // Find the position | |
515 | pos1 = pos2 = 0; | |
516 | dpos = 0; | |
517 | do { | |
518 | dpos = energy - vxe[pos2++]; | |
519 | } | |
520 | while (dpos > 0); | |
521 | pos2--; | |
522 | if (pos2 > nV) pos2 = nV; | |
523 | pos1 = pos2 - 1; | |
524 | ||
525 | // Differentiate between the sampling points | |
526 | dnde = (vye[pos1] - vye[pos2]) / (vxe[pos2] - vxe[pos1]); | |
527 | ||
528 | return dnde; | |
529 | ||
530 | } |