2 /**************************************************************************
3 * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
5 * Author: The ALICE Off-line Project. *
6 * Contributors are mentioned in the code where appropriate. *
8 * Permission to use, copy, modify and distribute this software and its *
9 * documentation strictly for non-commercial purposes is hereby granted *
10 * without fee, provided that the above copyright notice appears in all *
11 * copies and that both the copyright notice and this permission notice *
12 * appear in the supporting documentation. The authors make no claims *
13 * about the suitability of this software for any purpose. It is *
14 * provided "as is" without express or implied warranty. *
15 **************************************************************************/
19 ////////////////////////////////////////////////////////////////////////////
21 // TRD simulation - multimodule (regular rad.) //
22 // after: M. CASTELLANO et al., COMP. PHYS. COMM. 51 (1988) 431 //
23 // + COMP. PHYS. COMM. 61 (1990) 395 //
25 // 17.07.1998 - A.Andronic //
26 // 08.12.1998 - simplified version //
27 // 11.07.2000 - Adapted code to aliroot environment (C.Blume) //
28 // 04.06.2004 - Momentum dependent parameters implemented (CBL) //
30 ////////////////////////////////////////////////////////////////////////////
35 #include <TVirtualMC.h>
36 #include <TVirtualMCStack.h>
38 #include "AliModule.h"
40 #include "AliTRDsimTR.h"
44 //_____________________________________________________________________________
45 AliTRDsimTR::AliTRDsimTR()
70 // AliTRDsimTR default constructor
77 //_____________________________________________________________________________
78 AliTRDsimTR::AliTRDsimTR(AliModule *mod, Int_t foil, Int_t gap)
103 // AliTRDsimTR constructor. Takes the material properties of the radiator
104 // foils and the gas in the gaps from AliModule <mod>.
105 // The default number of foils is 100 with a thickness of 20 mu. The
106 // thickness of the gaps is 500 mu.
124 mod->AliGetMaterial(foil,name,aFoil,zFoil,rhoFoil,rad,abs);
125 mod->AliGetMaterial(gap ,name,aGap ,zGap ,rhoGap ,rad,abs);
130 fFoilOmega = Omega(fFoilDens,fFoilZ,fFoilA);
135 fGapOmega = Omega(fGapDens ,fGapZ ,fGapA );
139 //_____________________________________________________________________________
140 AliTRDsimTR::AliTRDsimTR(const AliTRDsimTR &s)
142 ,fNFoilsDim(s.fNFoilsDim)
145 ,fFoilThick(s.fFoilThick)
146 ,fGapThick(s.fGapThick)
147 ,fFoilDens(s.fFoilDens)
148 ,fGapDens(s.fGapDens)
149 ,fFoilOmega(s.fFoilOmega)
150 ,fGapOmega(s.fGapOmega)
156 ,fSpNBins(s.fSpNBins)
157 ,fSpRange(s.fSpRange)
158 ,fSpBinWidth(s.fSpBinWidth)
159 ,fSpLower(s.fSpLower)
160 ,fSpUpper(s.fSpUpper)
165 // AliTRDsimTR copy constructor
168 fNFoils = new Int_t[fNFoilsDim];
169 for (Int_t iFoil = 0; iFoil < fNFoilsDim; iFoil++) {
170 fNFoils[iFoil] = ((AliTRDsimTR &) s).fNFoils[iFoil];
173 fNFoilsUp = new Double_t[fNFoilsDim];
174 for (Int_t iFoil = 0; iFoil < fNFoilsDim; iFoil++) {
175 fNFoilsUp[iFoil] = ((AliTRDsimTR &) s).fNFoilsUp[iFoil];
178 fSigma = new Double_t[fSpNBins];
179 for (Int_t iBin = 0; iBin < fSpNBins; iBin++) {
180 fSigma[iBin] = ((AliTRDsimTR &) s).fSigma[iBin];
185 //_____________________________________________________________________________
186 AliTRDsimTR::~AliTRDsimTR()
189 // AliTRDsimTR destructor
214 //_____________________________________________________________________________
215 AliTRDsimTR &AliTRDsimTR::operator=(const AliTRDsimTR &s)
218 // Assignment operator
221 if (this != &s) ((AliTRDsimTR &) s).Copy(*this);
227 //_____________________________________________________________________________
228 void AliTRDsimTR::Copy(TObject &s) const
234 ((AliTRDsimTR &) s).fFoilThick = fFoilThick;
235 ((AliTRDsimTR &) s).fFoilDens = fFoilDens;
236 ((AliTRDsimTR &) s).fFoilOmega = fFoilOmega;
237 ((AliTRDsimTR &) s).fFoilZ = fFoilZ;
238 ((AliTRDsimTR &) s).fFoilA = fFoilA;
239 ((AliTRDsimTR &) s).fGapThick = fGapThick;
240 ((AliTRDsimTR &) s).fGapDens = fGapDens;
241 ((AliTRDsimTR &) s).fGapOmega = fGapOmega;
242 ((AliTRDsimTR &) s).fGapZ = fGapZ;
243 ((AliTRDsimTR &) s).fGapA = fGapA;
244 ((AliTRDsimTR &) s).fTemp = fTemp;
245 ((AliTRDsimTR &) s).fSpNBins = fSpNBins;
246 ((AliTRDsimTR &) s).fSpRange = fSpRange;
247 ((AliTRDsimTR &) s).fSpBinWidth = fSpBinWidth;
248 ((AliTRDsimTR &) s).fSpLower = fSpLower;
249 ((AliTRDsimTR &) s).fSpUpper = fSpUpper;
251 if (((AliTRDsimTR &) s).fNFoils) {
252 delete [] ((AliTRDsimTR &) s).fNFoils;
254 ((AliTRDsimTR &) s).fNFoils = new Int_t[fNFoilsDim];
255 for (Int_t iFoil = 0; iFoil < fNFoilsDim; iFoil++) {
256 ((AliTRDsimTR &) s).fNFoils[iFoil] = fNFoils[iFoil];
259 if (((AliTRDsimTR &) s).fNFoilsUp) {
260 delete [] ((AliTRDsimTR &) s).fNFoilsUp;
262 ((AliTRDsimTR &) s).fNFoilsUp = new Double_t[fNFoilsDim];
263 for (Int_t iFoil = 0; iFoil < fNFoilsDim; iFoil++) {
264 ((AliTRDsimTR &) s).fNFoilsUp[iFoil] = fNFoilsUp[iFoil];
267 if (((AliTRDsimTR &) s).fSigma) {
268 delete [] ((AliTRDsimTR &) s).fSigma;
270 ((AliTRDsimTR &) s).fSigma = new Double_t[fSpNBins];
271 for (Int_t iBin = 0; iBin < fSpNBins; iBin++) {
272 ((AliTRDsimTR &) s).fSigma[iBin] = fSigma[iBin];
277 //_____________________________________________________________________________
278 void AliTRDsimTR::Init()
282 // The default radiator are prolypropilene foils of 10 mu thickness
283 // with gaps of 80 mu filled with N2.
291 fNFoils = new Int_t[fNFoilsDim];
303 fNFoilsUp = new Double_t[fNFoilsDim];
310 fNFoilsUp[6] = 10000.0;
316 fFoilOmega = Omega(fFoilDens,fFoilZ,fFoilA);
322 fGapOmega = Omega(fGapDens ,fGapZ ,fGapA );
328 fSpBinWidth = fSpRange / fSpNBins;
329 fSpLower = 1.0 - 0.5 * fSpBinWidth;
330 fSpUpper = fSpLower + fSpRange;
332 if (fSpectrum) delete fSpectrum;
333 fSpectrum = new TH1D("TRspectrum","TR spectrum",fSpNBins,fSpLower,fSpUpper);
334 fSpectrum->SetDirectory(0);
336 // Set the sigma values
341 //_____________________________________________________________________________
342 Int_t AliTRDsimTR::CreatePhotons(Int_t pdg, Float_t p
343 , Int_t &nPhoton, Float_t *ePhoton)
346 // Create TRD photons for a charged particle of type <pdg> with the total
348 // Number of produced TR photons: <nPhoton>
349 // Energies of the produced TR photons: <ePhoton>
353 const Int_t kPdgEle = 11;
354 const Int_t kPdgMuon = 13;
355 const Int_t kPdgPion = 211;
356 const Int_t kPdgKaon = 321;
359 switch (TMath::Abs(pdg)) {
377 // Calculate the TR photons
378 return TrPhotons(p, mass, nPhoton, ePhoton);
382 //_____________________________________________________________________________
383 Int_t AliTRDsimTR::TrPhotons(Float_t p, Float_t mass
384 , Int_t &nPhoton, Float_t *ePhoton)
387 // Produces TR photons using a parametric model for regular radiator. Photons
388 // with energy larger than 15 keV are included in the MC stack and tracked by VMC
392 // p - parent momentum [GeV/c]
393 // mass - parent mass
396 // nPhoton - number of photons which have to be processed by custom code
397 // ePhoton - energy of this photons in keV.
400 const Double_t kAlpha = 0.0072973;
401 const Int_t kSumMax = 30;
403 Double_t tau = fGapThick / fFoilThick;
406 Double_t gamma = TMath::Sqrt(p*p + mass*mass) / mass;
408 // Select the number of foils corresponding to momentum
409 Int_t foils = SelectNFoils(p);
425 for (Int_t iBin = 1; iBin <= fSpNBins; iBin++) {
427 energykeV = fSpectrum->GetBinCenter(iBin);
428 energyeV = energykeV * 1.0e3;
430 sigma = Sigma(energykeV);
432 csi1 = fFoilOmega / energyeV;
433 csi2 = fGapOmega / energyeV;
435 rho1 = 2.5 * energyeV * fFoilThick * 1.0e4
436 * (1.0 / (gamma*gamma) + csi1*csi1);
437 rho2 = 2.5 * energyeV * fFoilThick * 1.0e4
438 * (1.0 / (gamma*gamma) + csi2 *csi2);
442 for (Int_t n = 1; n <= kSumMax; n++) {
443 thetaN = (TMath::Pi() * 2.0 * n - (rho1 + tau * rho2)) / (1.0 + tau);
447 aux = 1.0 / (rho1 + thetaN) - 1.0 / (rho2 + thetaN);
448 sum += thetaN * (aux*aux) * (1.0 - TMath::Cos(rho1 + thetaN));
451 // Equivalent number of foils
452 nEqu = (1.0 - TMath::Exp(-foils * sigma)) / (1.0 - TMath::Exp(-sigma));
455 fSpectrum->SetBinContent(iBin,4.0 * kAlpha * nEqu * sum / (energykeV * (1.0 + tau)));
459 // <nTR> (binsize corr.)
460 Float_t nTr = fSpBinWidth * fSpectrum->Integral();
461 // Number of TR photons from Poisson distribution with mean <nTr>
462 Int_t nPhCand = gRandom->Poisson(nTr);
464 // Link the MC stack and get info about parent electron
465 TVirtualMCStack *stack = gMC->GetStack();
466 Int_t track = stack->GetCurrentTrackNumber();
467 Double_t px, py, pz, ptot;
468 gMC->TrackMomentum(px,py,pz,ptot);
469 ptot = TMath::Sqrt(px*px+py*py+pz*pz);
474 // Current position of electron
478 gMC->TrackPosition(x,y,z);
479 Double_t t = gMC->TrackTime();
481 // Counter for TR analysed in custom code (e < 15keV)
484 for (Int_t iPhoton = 0; iPhoton < nPhCand; iPhoton++) {
486 // Energy of the TR photon
487 Double_t e = fSpectrum->GetRandom();
489 // Put TR photon on particle stack
492 e *= 1.0e-6; // Convert it to GeV
495 stack->PushTrack(1 // Must be 1
496 ,track // Identifier of the parent track, -1 for a primary
497 ,22 // Particle code.
498 ,px*e // 4 momentum (The photon is generated on the same
499 ,py*e // direction as the parent. For irregular radiator one
500 ,pz*e // can calculate also the angle but this is a secondary
503 ,0.0,0.0,0.0 // Polarisation
504 ,kPFeedBackPhoton // Production mechanism (there is no TR in G3 so one
505 // has to make some convention)
506 ,phtrack // On output the number of the track stored
511 // Custom treatment of TR photons
514 ePhoton[nPhoton++] = e;
524 //_____________________________________________________________________________
525 void AliTRDsimTR::SetSigma()
528 // Sets the absorbtion crosssection for the energies of the TR spectrum
534 fSigma = new Double_t[fSpNBins];
536 for (Int_t iBin = 0; iBin < fSpNBins; iBin++) {
537 Double_t energykeV = iBin * fSpBinWidth + 1.0;
538 fSigma[iBin] = Sigma(energykeV);
543 //_____________________________________________________________________________
544 Double_t AliTRDsimTR::Sigma(Double_t energykeV)
547 // Calculates the absorbtion crosssection for a one-foil-one-gap-radiator
551 Double_t energyMeV = energykeV * 0.001;
552 if (energyMeV >= 0.001) {
553 return(GetMuPo(energyMeV) * fFoilDens * fFoilThick +
554 GetMuAi(energyMeV) * fGapDens * fGapThick * GetTemp());
562 //_____________________________________________________________________________
563 Double_t AliTRDsimTR::GetMuPo(Double_t energyMeV)
566 // Returns the photon absorbtion cross section for polypropylene
571 Double_t mu[kN] = { 1.894E+03, 5.999E+02, 2.593E+02
572 , 7.743E+01, 3.242E+01, 1.643E+01
573 , 9.432E+00, 3.975E+00, 2.088E+00
574 , 7.452E-01, 4.315E-01, 2.706E-01
575 , 2.275E-01, 2.084E-01, 1.970E-01
576 , 1.823E-01, 1.719E-01, 1.534E-01
577 , 1.402E-01, 1.217E-01, 1.089E-01
578 , 9.947E-02, 9.198E-02, 8.078E-02
579 , 7.262E-02, 6.495E-02, 5.910E-02
580 , 5.064E-02, 4.045E-02, 3.444E-02
581 , 3.045E-02, 2.760E-02, 2.383E-02
582 , 2.145E-02, 1.819E-02, 1.658E-02 };
584 Double_t en[kN] = { 1.000E-03, 1.500E-03, 2.000E-03
585 , 3.000E-03, 4.000E-03, 5.000E-03
586 , 6.000E-03, 8.000E-03, 1.000E-02
587 , 1.500E-02, 2.000E-02, 3.000E-02
588 , 4.000E-02, 5.000E-02, 6.000E-02
589 , 8.000E-02, 1.000E-01, 1.500E-01
590 , 2.000E-01, 3.000E-01, 4.000E-01
591 , 5.000E-01, 6.000E-01, 8.000E-01
592 , 1.000E+00, 1.250E+00, 1.500E+00
593 , 2.000E+00, 3.000E+00, 4.000E+00
594 , 5.000E+00, 6.000E+00, 8.000E+00
595 , 1.000E+01, 1.500E+01, 2.000E+01 };
597 return Interpolate(energyMeV,en,mu,kN);
601 //_____________________________________________________________________________
602 Double_t AliTRDsimTR::GetMuCO(Double_t energyMeV)
605 // Returns the photon absorbtion cross section for CO2
610 Double_t mu[kN] = { 0.39383E+04, 0.13166E+04, 0.58750E+03
611 , 0.18240E+03, 0.77996E+02, 0.40024E+02
612 , 0.23116E+02, 0.96997E+01, 0.49726E+01
613 , 0.15543E+01, 0.74915E+00, 0.34442E+00
614 , 0.24440E+00, 0.20589E+00, 0.18632E+00
615 , 0.16578E+00, 0.15394E+00, 0.13558E+00
616 , 0.12336E+00, 0.10678E+00, 0.95510E-01
617 , 0.87165E-01, 0.80587E-01, 0.70769E-01
618 , 0.63626E-01, 0.56894E-01, 0.51782E-01
619 , 0.44499E-01, 0.35839E-01, 0.30825E-01
620 , 0.27555E-01, 0.25269E-01, 0.22311E-01
621 , 0.20516E-01, 0.18184E-01, 0.17152E-01 };
623 Double_t en[kN] = { 0.10000E-02, 0.15000E-02, 0.20000E-02
624 , 0.30000E-02, 0.40000E-02, 0.50000E-02
625 , 0.60000E-02, 0.80000E-02, 0.10000E-01
626 , 0.15000E-01, 0.20000E-01, 0.30000E-01
627 , 0.40000E-01, 0.50000E-01, 0.60000E-01
628 , 0.80000E-01, 0.10000E+00, 0.15000E+00
629 , 0.20000E+00, 0.30000E+00, 0.40000E+00
630 , 0.50000E+00, 0.60000E+00, 0.80000E+00
631 , 0.10000E+01, 0.12500E+01, 0.15000E+01
632 , 0.20000E+01, 0.30000E+01, 0.40000E+01
633 , 0.50000E+01, 0.60000E+01, 0.80000E+01
634 , 0.10000E+02, 0.15000E+02, 0.20000E+02 };
636 return Interpolate(energyMeV,en,mu,kN);
640 //_____________________________________________________________________________
641 Double_t AliTRDsimTR::GetMuXe(Double_t energyMeV)
644 // Returns the photon absorbtion cross section for xenon
649 Double_t mu[kN] = { 9.413E+03, 8.151E+03, 7.035E+03
650 , 7.338E+03, 4.085E+03, 2.088E+03
651 , 7.780E+02, 3.787E+02, 2.408E+02
652 , 6.941E+02, 6.392E+02, 6.044E+02
653 , 8.181E+02, 7.579E+02, 6.991E+02
654 , 8.064E+02, 6.376E+02, 3.032E+02
655 , 1.690E+02, 5.743E+01, 2.652E+01
656 , 8.930E+00, 6.129E+00, 3.316E+01
657 , 2.270E+01, 1.272E+01, 7.825E+00
658 , 3.633E+00, 2.011E+00, 7.202E-01
659 , 3.760E-01, 1.797E-01, 1.223E-01
660 , 9.699E-02, 8.281E-02, 6.696E-02
661 , 5.785E-02, 5.054E-02, 4.594E-02
662 , 4.078E-02, 3.681E-02, 3.577E-02
663 , 3.583E-02, 3.634E-02, 3.797E-02
664 , 3.987E-02, 4.445E-02, 4.815E-02 };
666 Double_t en[kN] = { 1.00000E-03, 1.07191E-03, 1.14900E-03
667 , 1.14900E-03, 1.50000E-03, 2.00000E-03
668 , 3.00000E-03, 4.00000E-03, 4.78220E-03
669 , 4.78220E-03, 5.00000E-03, 5.10370E-03
670 , 5.10370E-03, 5.27536E-03, 5.45280E-03
671 , 5.45280E-03, 6.00000E-03, 8.00000E-03
672 , 1.00000E-02, 1.50000E-02, 2.00000E-02
673 , 3.00000E-02, 3.45614E-02, 3.45614E-02
674 , 4.00000E-02, 5.00000E-02, 6.00000E-02
675 , 8.00000E-02, 1.00000E-01, 1.50000E-01
676 , 2.00000E-01, 3.00000E-01, 4.00000E-01
677 , 5.00000E-01, 6.00000E-01, 8.00000E-01
678 , 1.00000E+00, 1.25000E+00, 1.50000E+00
679 , 2.00000E+00, 3.00000E+00, 4.00000E+00
680 , 5.00000E+00, 6.00000E+00, 8.00000E+00
681 , 1.00000E+01, 1.50000E+01, 2.00000E+01 };
683 return Interpolate(energyMeV,en,mu,kN);
687 //_____________________________________________________________________________
688 Double_t AliTRDsimTR::GetMuAr(Double_t energyMeV)
691 // Returns the photon absorbtion cross section for argon
696 Double_t mu[kN] = { 3.184E+03, 1.105E+03, 5.120E+02
697 , 1.703E+02, 1.424E+02, 1.275E+03
698 , 7.572E+02, 4.225E+02, 2.593E+02
699 , 1.180E+02, 6.316E+01, 1.983E+01
700 , 8.629E+00, 2.697E+00, 1.228E+00
701 , 7.012E-01, 4.664E-01, 2.760E-01
702 , 2.043E-01, 1.427E-01, 1.205E-01
703 , 9.953E-02, 8.776E-02, 7.958E-02
704 , 7.335E-02, 6.419E-02, 5.762E-02
705 , 5.150E-02, 4.695E-02, 4.074E-02
706 , 3.384E-02, 3.019E-02, 2.802E-02
707 , 2.667E-02, 2.517E-02, 2.451E-02
708 , 2.418E-02, 2.453E-02 };
710 Double_t en[kN] = { 1.00000E-03, 1.50000E-03, 2.00000E-03
711 , 3.00000E-03, 3.20290E-03, 3.20290E-03
712 , 4.00000E-03, 5.00000E-03, 6.00000E-03
713 , 8.00000E-03, 1.00000E-02, 1.50000E-02
714 , 2.00000E-02, 3.00000E-02, 4.00000E-02
715 , 5.00000E-02, 6.00000E-02, 8.00000E-02
716 , 1.00000E-01, 1.50000E-01, 2.00000E-01
717 , 3.00000E-01, 4.00000E-01, 5.00000E-01
718 , 6.00000E-01, 8.00000E-01, 1.00000E+00
719 , 1.25000E+00, 1.50000E+00, 2.00000E+00
720 , 3.00000E+00, 4.00000E+00, 5.00000E+00
721 , 6.00000E+00, 8.00000E+00, 1.00000E+01
722 , 1.50000E+01, 2.00000E+01 };
724 return Interpolate(energyMeV,en,mu,kN);
728 //_____________________________________________________________________________
729 Double_t AliTRDsimTR::GetMuMy(Double_t energyMeV)
732 // Returns the photon absorbtion cross section for mylar
737 Double_t mu[kN] = { 2.911E+03, 9.536E+02, 4.206E+02
738 , 1.288E+02, 5.466E+01, 2.792E+01
739 , 1.608E+01, 6.750E+00, 3.481E+00
740 , 1.132E+00, 5.798E-01, 3.009E-01
741 , 2.304E-01, 2.020E-01, 1.868E-01
742 , 1.695E-01, 1.586E-01, 1.406E-01
743 , 1.282E-01, 1.111E-01, 9.947E-02
744 , 9.079E-02, 8.395E-02, 7.372E-02
745 , 6.628E-02, 5.927E-02, 5.395E-02
746 , 4.630E-02, 3.715E-02, 3.181E-02
747 , 2.829E-02, 2.582E-02, 2.257E-02
748 , 2.057E-02, 1.789E-02, 1.664E-02 };
750 Double_t en[kN] = { 1.00000E-03, 1.50000E-03, 2.00000E-03
751 , 3.00000E-03, 4.00000E-03, 5.00000E-03
752 , 6.00000E-03, 8.00000E-03, 1.00000E-02
753 , 1.50000E-02, 2.00000E-02, 3.00000E-02
754 , 4.00000E-02, 5.00000E-02, 6.00000E-02
755 , 8.00000E-02, 1.00000E-01, 1.50000E-01
756 , 2.00000E-01, 3.00000E-01, 4.00000E-01
757 , 5.00000E-01, 6.00000E-01, 8.00000E-01
758 , 1.00000E+00, 1.25000E+00, 1.50000E+00
759 , 2.00000E+00, 3.00000E+00, 4.00000E+00
760 , 5.00000E+00, 6.00000E+00, 8.00000E+00
761 , 1.00000E+01, 1.50000E+01, 2.00000E+01 };
763 return Interpolate(energyMeV,en,mu,kN);
767 //_____________________________________________________________________________
768 Double_t AliTRDsimTR::GetMuN2(Double_t energyMeV)
771 // Returns the photon absorbtion cross section for nitrogen
776 Double_t mu[kN] = { 3.311E+03, 1.083E+03, 4.769E+02
777 , 1.456E+02, 6.166E+01, 3.144E+01
778 , 1.809E+01, 7.562E+00, 3.879E+00
779 , 1.236E+00, 6.178E-01, 3.066E-01
780 , 2.288E-01, 1.980E-01, 1.817E-01
781 , 1.639E-01, 1.529E-01, 1.353E-01
782 , 1.233E-01, 1.068E-01, 9.557E-02
783 , 8.719E-02, 8.063E-02, 7.081E-02
784 , 6.364E-02, 5.693E-02, 5.180E-02
785 , 4.450E-02, 3.579E-02, 3.073E-02
786 , 2.742E-02, 2.511E-02, 2.209E-02
787 , 2.024E-02, 1.782E-02, 1.673E-02 };
789 Double_t en[kN] = { 1.00000E-03, 1.50000E-03, 2.00000E-03
790 , 3.00000E-03, 4.00000E-03, 5.00000E-03
791 , 6.00000E-03, 8.00000E-03, 1.00000E-02
792 , 1.50000E-02, 2.00000E-02, 3.00000E-02
793 , 4.00000E-02, 5.00000E-02, 6.00000E-02
794 , 8.00000E-02, 1.00000E-01, 1.50000E-01
795 , 2.00000E-01, 3.00000E-01, 4.00000E-01
796 , 5.00000E-01, 6.00000E-01, 8.00000E-01
797 , 1.00000E+00, 1.25000E+00, 1.50000E+00
798 , 2.00000E+00, 3.00000E+00, 4.00000E+00
799 , 5.00000E+00, 6.00000E+00, 8.00000E+00
800 , 1.00000E+01, 1.50000E+01, 2.00000E+01 };
802 return Interpolate(energyMeV,en,mu,kN);
806 //_____________________________________________________________________________
807 Double_t AliTRDsimTR::GetMuO2(Double_t energyMeV)
810 // Returns the photon absorbtion cross section for oxygen
815 Double_t mu[kN] = { 4.590E+03, 1.549E+03, 6.949E+02
816 , 2.171E+02, 9.315E+01, 4.790E+01
817 , 2.770E+01, 1.163E+01, 5.952E+00
818 , 1.836E+00, 8.651E-01, 3.779E-01
819 , 2.585E-01, 2.132E-01, 1.907E-01
820 , 1.678E-01, 1.551E-01, 1.361E-01
821 , 1.237E-01, 1.070E-01, 9.566E-02
822 , 8.729E-02, 8.070E-02, 7.087E-02
823 , 6.372E-02, 5.697E-02, 5.185E-02
824 , 4.459E-02, 3.597E-02, 3.100E-02
825 , 2.777E-02, 2.552E-02, 2.263E-02
826 , 2.089E-02, 1.866E-02, 1.770E-02 };
828 Double_t en[kN] = { 1.00000E-03, 1.50000E-03, 2.00000E-03
829 , 3.00000E-03, 4.00000E-03, 5.00000E-03
830 , 6.00000E-03, 8.00000E-03, 1.00000E-02
831 , 1.50000E-02, 2.00000E-02, 3.00000E-02
832 , 4.00000E-02, 5.00000E-02, 6.00000E-02
833 , 8.00000E-02, 1.00000E-01, 1.50000E-01
834 , 2.00000E-01, 3.00000E-01, 4.00000E-01
835 , 5.00000E-01, 6.00000E-01, 8.00000E-01
836 , 1.00000E+00, 1.25000E+00, 1.50000E+00
837 , 2.00000E+00, 3.00000E+00, 4.00000E+00
838 , 5.00000E+00, 6.00000E+00, 8.00000E+00
839 , 1.00000E+01, 1.50000E+01, 2.00000E+01 };
841 return Interpolate(energyMeV,en,mu,kN);
845 //_____________________________________________________________________________
846 Double_t AliTRDsimTR::GetMuHe(Double_t energyMeV)
849 // Returns the photon absorbtion cross section for helium
854 Double_t mu[kN] = { 6.084E+01, 1.676E+01, 6.863E+00
855 , 2.007E+00, 9.329E-01, 5.766E-01
856 , 4.195E-01, 2.933E-01, 2.476E-01
857 , 2.092E-01, 1.960E-01, 1.838E-01
858 , 1.763E-01, 1.703E-01, 1.651E-01
859 , 1.562E-01, 1.486E-01, 1.336E-01
860 , 1.224E-01, 1.064E-01, 9.535E-02
861 , 8.707E-02, 8.054E-02, 7.076E-02
862 , 6.362E-02, 5.688E-02, 5.173E-02
863 , 4.422E-02, 3.503E-02, 2.949E-02
864 , 2.577E-02, 2.307E-02, 1.940E-02
865 , 1.703E-02, 1.363E-02, 1.183E-02 };
867 Double_t en[kN] = { 1.00000E-03, 1.50000E-03, 2.00000E-03
868 , 3.00000E-03, 4.00000E-03, 5.00000E-03
869 , 6.00000E-03, 8.00000E-03, 1.00000E-02
870 , 1.50000E-02, 2.00000E-02, 3.00000E-02
871 , 4.00000E-02, 5.00000E-02, 6.00000E-02
872 , 8.00000E-02, 1.00000E-01, 1.50000E-01
873 , 2.00000E-01, 3.00000E-01, 4.00000E-01
874 , 5.00000E-01, 6.00000E-01, 8.00000E-01
875 , 1.00000E+00, 1.25000E+00, 1.50000E+00
876 , 2.00000E+00, 3.00000E+00, 4.00000E+00
877 , 5.00000E+00, 6.00000E+00, 8.00000E+00
878 , 1.00000E+01, 1.50000E+01, 2.00000E+01 };
880 return Interpolate(energyMeV,en,mu,kN);
884 //_____________________________________________________________________________
885 Double_t AliTRDsimTR::GetMuAi(Double_t energyMeV)
888 // Returns the photon absorbtion cross section for air
889 // Implemented by Oliver Busch
894 Double_t mu[kN] = { 0.35854E+04, 0.11841E+04, 0.52458E+03,
895 0.16143E+03, 0.14250E+03, 0.15722E+03,
896 0.77538E+02, 0.40099E+02, 0.23313E+02,
897 0.98816E+01, 0.51000E+01, 0.16079E+01,
898 0.77536E+00, 0.35282E+00, 0.24790E+00,
899 0.20750E+00, 0.18703E+00, 0.16589E+00,
900 0.15375E+00, 0.13530E+00, 0.12311E+00,
901 0.10654E+00, 0.95297E-01, 0.86939E-01,
902 0.80390E-01, 0.70596E-01, 0.63452E-01,
903 0.56754E-01, 0.51644E-01, 0.44382E-01,
904 0.35733E-01, 0.30721E-01, 0.27450E-01,
905 0.25171E-01, 0.22205E-01, 0.20399E-01,
906 0.18053E-01, 0.18057E-01 };
910 Double_t en[kN] = { 0.10000E-02, 0.15000E-02, 0.20000E-02,
911 0.30000E-02, 0.32029E-02, 0.32029E-02,
912 0.40000E-02, 0.50000E-02, 0.60000E-02,
913 0.80000E-02, 0.10000E-01, 0.15000E-01,
914 0.20000E-01, 0.30000E-01, 0.40000E-01,
915 0.50000E-01, 0.60000E-01, 0.80000E-01,
916 0.10000E+00, 0.15000E+00, 0.20000E+00,
917 0.30000E+00, 0.40000E+00, 0.50000E+00,
918 0.60000E+00, 0.80000E+00, 0.10000E+01,
919 0.12500E+01, 0.15000E+01, 0.20000E+01,
920 0.30000E+01, 0.40000E+01, 0.50000E+01,
921 0.60000E+01, 0.80000E+01, 0.10000E+02,
922 0.15000E+02, 0.20000E+02 };
924 return Interpolate(energyMeV,en,mu,kN);
928 //_____________________________________________________________________________
929 Double_t AliTRDsimTR::Interpolate(Double_t energyMeV
931 , const Double_t * const mu
935 // Interpolates the photon absorbtion cross section
936 // for a given energy <energyMeV>.
941 Int_t istat = Locate(en,n,energyMeV,index,de);
943 return (mu[index] - de * (mu[index] - mu[index+1])
944 / (en[index+1] - en[index] ));
952 //_____________________________________________________________________________
953 Int_t AliTRDsimTR::Locate(Double_t *xv, Int_t n, Double_t xval
954 , Int_t &kl, Double_t &dx)
957 // Locates a point (xval) in a 1-dim grid (xv(n))
960 if (xval >= xv[n-1]) {
971 while (kh - kl > 1) {
972 if (xval < xv[km = (kl+kh)/2]) {
979 if ((xval < xv[kl]) ||
982 AliFatal(Form("Locate failed xv[%d] %f xval %f xv[%d] %f!!!\n"
983 ,kl,xv[kl],xval,kl+1,xv[kl+1]));
993 //_____________________________________________________________________________
994 Int_t AliTRDsimTR::SelectNFoils(Float_t p) const
997 // Selects the number of foils corresponding to the momentum
1000 Int_t foils = fNFoils[fNFoilsDim-1];
1002 for (Int_t iFoil = 0; iFoil < fNFoilsDim; iFoil++) {
1003 if (p < fNFoilsUp[iFoil]) {
1004 foils = fNFoils[iFoil];