TRD/AliTRDSimParam.cxx

   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 /* $Id$ */
  17
  18 ////////////////////////////////////////////////////////////////////////////
  19 //                                                                        //
  20 // Class containing constant simulation parameters                        //
  21 //                                                                        //
  22 // Request an instance with AliTRDSimParam::Instance()                    //
  23 // Then request the needed values                                         //
  24 //                                                                        //
  25 ////////////////////////////////////////////////////////////////////////////
  26
  27 #include <TMath.h>
  28
  29 #include "AliRun.h"
  30
  31 #include "AliTRDSimParam.h"
  32 #include "AliTRDCommonParam.h"
  33
  34 ClassImp(AliTRDSimParam)
  35
  36 AliTRDSimParam *AliTRDSimParam::fgInstance   = 0;
  37 Bool_t          AliTRDSimParam::fgTerminated = kFALSE;
  38
  39 //_ singleton implementation __________________________________________________
  40 AliTRDSimParam* AliTRDSimParam::Instance()
  41 {
  42   //
  43   // Singleton implementation
  44   // Returns an instance of this class, it is created if neccessary
  45   //
  46
  47   if (fgTerminated != kFALSE) {
  48     return 0;
  49   }
  50
  51   if (fgInstance == 0) {
  52     fgInstance = new AliTRDSimParam();
  53   }
  54
  55   return fgInstance;
  56
  57 }
  58
  59 //_ singleton implementation __________________________________________________
  60 void AliTRDSimParam::Terminate()
  61 {
  62   //
  63   // Singleton implementation
  64   // Deletes the instance of this class and sets the terminated flag,
  65   // instances cannot be requested anymore
  66   // This function can be called several times.
  67   //
  68
  69   fgTerminated = kTRUE;
  70
  71   if (fgInstance != 0) {
  72     delete fgInstance;
  73     fgInstance = 0;
  74   }
  75
  76 }
  77
  78 //_____________________________________________________________________________
  79 AliTRDSimParam::AliTRDSimParam()
  80   :TObject()
  81   ,fGasGain(0.0)
  82   ,fNoise(0.0)
  83   ,fChipGain(0.0)
  84   ,fADCoutRange(0.0)
  85   ,fADCinRange(0.0)
  86   ,fADCbaseline(0)
  87   ,fDiffusionOn(kFALSE)
  88   ,fElAttachOn(kFALSE)
  89   ,fElAttachProp(0.0)
  90   ,fTRFOn(kFALSE)
  91   ,fTRFsmp(0)
  92   ,fTRFbin(0)
  93   ,fTRFlo(0.0)
  94   ,fTRFhi(0.0)
  95   ,fTRFwid(0.0)
  96   ,fCTOn(kFALSE)
  97   ,fCTsmp(0)
  98   ,fPadCoupling(0.0)
  99   ,fTimeCoupling(0.0)
 100   ,fTimeStructOn(kFALSE)
 101   ,fPRFOn(kFALSE)
 102   ,fNTimeBins(0)
 103 {
 104   //
 105   // Default constructor
 106   //
 107
 108   Init();
 109
 110 }
 111
 112 //_____________________________________________________________________________
 113 void AliTRDSimParam::Init()
 114 {
 115   //
 116   // Default initializiation
 117   //
 118
 119   // The default parameter for the digitization
 120   fGasGain           = 4000.0;
 121   fChipGain          =   12.4;
 122   fNoise             = 1250.0;
 123   fADCoutRange       = 1023.0;          // 10-bit ADC
 124   fADCinRange        = 2000.0;          // 2V input range
 125   fADCbaseline       =   10;
 126
 127   // Diffusion on
 128   fDiffusionOn       = kTRUE;
 129
 130   // Propability for electron attachment
 131   fElAttachOn        = kFALSE;
 132   fElAttachProp      = 0.0;
 133
 134   // The time response function
 135   fTRFOn             = kTRUE;
 136
 137   // The cross talk
 138   fCTOn              = kTRUE;
 139
 140   // The pad coupling factor
 141   // Use 0.46, instead of the theroetical value 0.3, since it reproduces better
 142   // the test beam data, even tough it is not understood why.
 143   fPadCoupling       = 0.46;
 144
 145   // The time coupling factor (same number as for the TPC)
 146   fTimeCoupling      = 0.4;
 147
 148   // Use drift time maps
 149   fTimeStructOn      = kTRUE;
 150
 151   // The pad response function
 152   fPRFOn             = kTRUE;
 153
 154   // The number of time bins
 155   //fNTimeBins         = 30;
 156   fNTimeBins         = 24;
 157
 158   ReInit();
 159
 160 }
 161
 162 //_____________________________________________________________________________
 163 AliTRDSimParam::~AliTRDSimParam()
 164 {
 165   //
 166   // Destructor
 167   //
 168
 169   if (fTRFsmp) {
 170     delete [] fTRFsmp;
 171     fTRFsmp = 0;
 172   }
 173
 174   if (fCTsmp) {
 175     delete [] fCTsmp;
 176     fCTsmp  = 0;
 177   }
 178
 179 }
 180
 181 //_____________________________________________________________________________
 182 AliTRDSimParam::AliTRDSimParam(const AliTRDSimParam &p)
 183   :TObject(p)
 184   ,fGasGain(p.fGasGain)
 185   ,fNoise(p.fNoise)
 186   ,fChipGain(p.fChipGain)
 187   ,fADCoutRange(p.fADCoutRange)
 188   ,fADCinRange(p.fADCinRange)
 189   ,fADCbaseline(p.fADCbaseline)
 190   ,fDiffusionOn(p.fDiffusionOn)
 191   ,fElAttachOn(p.fElAttachOn)
 192   ,fElAttachProp(p.fElAttachProp)
 193   ,fTRFOn(p.fTRFOn)
 194   ,fTRFsmp(0)
 195   ,fTRFbin(p.fTRFbin)
 196   ,fTRFlo(p.fTRFlo)
 197   ,fTRFhi(p.fTRFhi)
 198   ,fTRFwid(p.fTRFwid)
 199   ,fCTOn(p.fCTOn)
 200   ,fCTsmp(0)
 201   ,fPadCoupling(p.fPadCoupling)
 202   ,fTimeCoupling(p.fTimeCoupling)
 203   ,fTimeStructOn(p.fTimeStructOn)
 204   ,fPRFOn(p.fPRFOn)
 205   ,fNTimeBins(p.fNTimeBins)
 206 {
 207   //
 208   // Copy constructor
 209   //
 210
 211   Int_t iBin = 0;
 212
 213   if (((AliTRDSimParam &) p).fTRFsmp) {
 214     delete [] ((AliTRDSimParam &) p).fTRFsmp;
 215   }
 216   ((AliTRDSimParam &) p).fTRFsmp = new Float_t[fTRFbin];
 217   for (iBin = 0; iBin < fTRFbin; iBin++) {
 218     ((AliTRDSimParam &) p).fTRFsmp[iBin] = fTRFsmp[iBin];
 219   }
 220
 221   if (((AliTRDSimParam &) p).fCTsmp) {
 222     delete [] ((AliTRDSimParam &) p).fCTsmp;
 223   }
 224   ((AliTRDSimParam &) p).fCTsmp  = new Float_t[fTRFbin];
 225   for (iBin = 0; iBin < fTRFbin; iBin++) {
 226     ((AliTRDSimParam &) p).fCTsmp[iBin] = fCTsmp[iBin];
 227   }
 228
 229 }
 230
 231 //_____________________________________________________________________________
 232 AliTRDSimParam &AliTRDSimParam::operator=(const AliTRDSimParam &p)
 233 {
 234   //
 235   // Assignment operator
 236   //
 237
 238   if (this != &p) {
 239     ((AliTRDSimParam &) p).Copy(*this);
 240   }
 241
 242   return *this;
 243
 244 }
 245
 246 //_____________________________________________________________________________
 247 void AliTRDSimParam::Copy(TObject &p) const
 248 {
 249   //
 250   // Copy function
 251   //
 252
 253   AliTRDSimParam *target = dynamic_cast<AliTRDSimParam *> (&p);
 254   if (!target) {
 255     return;
 256   }
 257
 258   target->fGasGain            = fGasGain;
 259   target->fNoise              = fNoise;
 260   target->fChipGain           = fChipGain;
 261   target->fADCoutRange        = fADCoutRange;
 262   target->fADCinRange         = fADCinRange;
 263   target->fADCbaseline        = fADCbaseline;
 264   target->fDiffusionOn        = fDiffusionOn;
 265   target->fElAttachOn         = fElAttachOn;
 266   target->fElAttachProp       = fElAttachProp;
 267   target->fTRFOn              = fTRFOn;
 268   target->fTRFbin             = fTRFbin;
 269   target->fTRFlo              = fTRFlo;
 270   target->fTRFhi              = fTRFhi;
 271   target->fTRFwid             = fTRFwid;
 272   target->fCTOn               = fCTOn;
 273   target->fPadCoupling        = fPadCoupling;
 274   target->fTimeCoupling       = fTimeCoupling;
 275   target->fPRFOn              = fPRFOn;
 276   target->fNTimeBins          = fNTimeBins;
 277
 278   if (target->fTRFsmp) {
 279     delete[] target->fTRFsmp;
 280   }
 281   target->fTRFsmp = new Float_t[fTRFbin];
 282   for (Int_t iBin = 0; iBin < fTRFbin; iBin++) {
 283     target->fTRFsmp[iBin] = fTRFsmp[iBin];
 284   }
 285
 286   if (target->fCTsmp) {
 287     delete[] target->fCTsmp;
 288   }
 289   target->fCTsmp  = new Float_t[fTRFbin];
 290   for (Int_t iBin = 0; iBin < fTRFbin; iBin++) {
 291     target->fCTsmp[iBin]  = fCTsmp[iBin];
 292   }
 293
 294 }
 295
 296 //_____________________________________________________________________________
 297 void AliTRDSimParam::ReInit()
 298 {
 299   //
 300   // Reinitializes the parameter class after a change
 301   //
 302
 303   if      (AliTRDCommonParam::Instance()->IsXenon()) {
 304     // The range and the binwidth for the sampled TRF
 305     fTRFbin = 200;
 306     // Start 0.2 mus before the signal
 307     fTRFlo  = -0.4;
 308     // End the maximum drift time after the signal
 309     fTRFhi  =  3.58;
 310     // Standard gas gain
 311     fGasGain = 4000.0;
 312   }
 313   else if (AliTRDCommonParam::Instance()->IsArgon()) {
 314     // The range and the binwidth for the sampled TRF
 315     fTRFbin  =  50;
 316     // Start 0.2 mus before the signal
 317     fTRFlo   =  0.02;
 318     // End the maximum drift time after the signal
 319     fTRFhi   =  1.98;
 320     // Higher gas gain
 321     fGasGain = 8000.0;
 322   }
 323   else {
 324     AliFatal("Not a valid gas mixture!");
 325     exit(1);
 326   }
 327   fTRFwid = (fTRFhi - fTRFlo) / ((Float_t) fTRFbin);
 328
 329   // Create the sampled TRF
 330   SampleTRF();
 331
 332 }
 333
 334 //_____________________________________________________________________________
 335 void AliTRDSimParam::SampleTRF()
 336 {
 337   //
 338   // Samples the new time response function.
 339   //
 340
 341   Int_t ipasa = 0;
 342
 343   // Xenon
 344   // From Antons measurements with Fe55 source, adjusted by C. Lippmann.
 345   // time bins are -0.4, -0.38, -0.36, ...., 3.54, 3.56, 3.58 microseconds
 346   const Int_t kNpasa     = 200;  // kNpasa should be equal to fTRFbin!
 347   Float_t xtalk[kNpasa];
 348   Float_t signal[kNpasa]     = { 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000
 349                                , 0.0002, 0.0007, 0.0026, 0.0089, 0.0253, 0.0612, 0.1319
 350                                , 0.2416, 0.3913, 0.5609, 0.7295, 0.8662, 0.9581, 1.0000
 351                                , 0.9990, 0.9611, 0.8995, 0.8269, 0.7495, 0.6714, 0.5987
 352                                , 0.5334, 0.4756, 0.4249, 0.3811, 0.3433, 0.3110, 0.2837
 353                                , 0.2607, 0.2409, 0.2243, 0.2099, 0.1974, 0.1868, 0.1776
 354                                , 0.1695, 0.1627, 0.1566, 0.1509, 0.1457, 0.1407, 0.1362
 355                                , 0.1317, 0.1274, 0.1233, 0.1196, 0.1162, 0.1131, 0.1102
 356                                , 0.1075, 0.1051, 0.1026, 0.1004, 0.0979, 0.0956, 0.0934
 357                                , 0.0912, 0.0892, 0.0875, 0.0858, 0.0843, 0.0829, 0.0815
 358                                , 0.0799, 0.0786, 0.0772, 0.0757, 0.0741, 0.0729, 0.0718
 359                                , 0.0706, 0.0692, 0.0680, 0.0669, 0.0655, 0.0643, 0.0630
 360                                , 0.0618, 0.0607, 0.0596, 0.0587, 0.0576, 0.0568, 0.0558
 361                                , 0.0550, 0.0541, 0.0531, 0.0522, 0.0513, 0.0505, 0.0497
 362                                , 0.0490, 0.0484, 0.0474, 0.0465, 0.0457, 0.0449, 0.0441
 363                                , 0.0433, 0.0425, 0.0417, 0.0410, 0.0402, 0.0395, 0.0388
 364                                , 0.0381, 0.0374, 0.0368, 0.0361, 0.0354, 0.0348, 0.0342
 365                                , 0.0336, 0.0330, 0.0324, 0.0318, 0.0312, 0.0306, 0.0301
 366                                , 0.0296, 0.0290, 0.0285, 0.0280, 0.0275, 0.0270, 0.0265
 367                                , 0.0260, 0.0256, 0.0251, 0.0246, 0.0242, 0.0238, 0.0233
 368                                , 0.0229, 0.0225, 0.0221, 0.0217, 0.0213, 0.0209, 0.0206
 369                                , 0.0202, 0.0198, 0.0195, 0.0191, 0.0188, 0.0184, 0.0181
 370                                , 0.0178, 0.0175, 0.0171, 0.0168, 0.0165, 0.0162, 0.0159
 371                                , 0.0157, 0.0154, 0.0151, 0.0148, 0.0146, 0.0143, 0.0140
 372                                , 0.0138, 0.0135, 0.0133, 0.0131, 0.0128, 0.0126, 0.0124
 373                                , 0.0121, 0.0119, 0.0120, 0.0115, 0.0113, 0.0111, 0.0109
 374                                , 0.0107, 0.0105, 0.0103, 0.0101, 0.0100, 0.0098, 0.0096
 375                                , 0.0094, 0.0092, 0.0091, 0.0089, 0.0088, 0.0086, 0.0084
 376                                , 0.0083, 0.0081, 0.0080, 0.0078 };
 377   signal[0] = 0.0;
 378   signal[1] = 0.0;
 379   signal[2] = 0.0;
 380   // With undershoot, positive peak corresponds to ~3% of the main signal:
 381   for (ipasa = 3; ipasa < kNpasa; ipasa++) {
 382     xtalk[ipasa] = 0.2 * (signal[ipasa-2] - signal[ipasa-3]);
 383   }
 384   xtalk[0]  = 0.0;
 385   xtalk[1]  = 0.0;
 386   xtalk[2]  = 0.0;
 387
 388   // Argon
 389   // Ar measurement with Fe55 source by Anton
 390   // time bins are 0.02, 0.06, 0.10, ...., 1.90, 1.94, 1.98 microseconds
 391   const Int_t kNpasaAr = 50;
 392   Float_t xtalkAr[kNpasaAr];
 393   Float_t signalAr[kNpasaAr] = { -0.01,  0.01,  0.00,  0.00,  0.01
 394                                , -0.01,  0.01,  2.15, 22.28, 55.53
 395                                , 68.52, 58.21, 40.92, 27.12, 18.49
 396                                , 13.42, 10.48,  8.67,  7.49,  6.55
 397                                ,  5.71,  5.12,  4.63,  4.22,  3.81
 398                                ,  3.48,  3.20,  2.94,  2.77,  2.63
 399                                ,  2.50,  2.37,  2.23,  2.13,  2.03
 400                                ,  1.91,  1.83,  1.75,  1.68,  1.63
 401                                ,  1.56,  1.49,  1.50,  1.49,  1.29
 402                                ,  1.19,  1.21,  1.21,  1.20,  1.10 };
 403   // Normalization to maximum
 404   for (ipasa = 0; ipasa < kNpasaAr; ipasa++) {
 405     signalAr[ipasa] /= 68.52;
 406   }
 407   signalAr[0] = 0.0;
 408   signalAr[1] = 0.0;
 409   signalAr[2] = 0.0;
 410   // With undershoot, positive peak corresponds to ~3% of the main signal:
 411   for (ipasa = 3; ipasa < kNpasaAr; ipasa++) {
 412     xtalkAr[ipasa] = 0.2 * (signalAr[ipasa-2] - signalAr[ipasa-3]);
 413   }
 414   xtalkAr[0]  = 0.0;
 415   xtalkAr[1]  = 0.0;
 416   xtalkAr[2]  = 0.0;
 417
 418   if (fTRFsmp) {
 419     delete [] fTRFsmp;
 420   }
 421   fTRFsmp = new Float_t[fTRFbin];
 422
 423   if (fCTsmp)  {
 424     delete [] fCTsmp;
 425   }
 426   fCTsmp  = new Float_t[fTRFbin];
 427
 428   if      (AliTRDCommonParam::Instance()->IsXenon()) {
 429     if (fTRFbin != kNpasa) {
 430       AliError("Array mismatch (xenon)\n\n");
 431     }
 432   }
 433   else if (AliTRDCommonParam::Instance()->IsArgon()) {
 434     if (fTRFbin != kNpasaAr) {
 435       AliError("Array mismatch (argon)\n\n");
 436     }
 437   }
 438
 439   for (Int_t iBin = 0; iBin < fTRFbin; iBin++) {
 440     if      (AliTRDCommonParam::Instance()->IsXenon()) {
 441       fTRFsmp[iBin] = signal[iBin];
 442       fCTsmp[iBin]  = xtalk[iBin];
 443     }
 444     else if (AliTRDCommonParam::Instance()->IsArgon()) {
 445       fTRFsmp[iBin] = signalAr[iBin];
 446       fCTsmp[iBin]  = xtalkAr[iBin];
 447     }
 448   }
 449
 450 }
 451
 452 //_____________________________________________________________________________
 453 Double_t AliTRDSimParam::TimeResponse(Double_t time) const
 454 {
 455   //
 456   // Applies the preamp shaper time response
 457   // (We assume a signal rise time of 0.2us = fTRFlo/2.
 458   //
 459
 460   Double_t rt   = (time - .5*fTRFlo) / fTRFwid;
 461   Int_t    iBin = (Int_t) rt;
 462   Double_t dt   = rt - iBin;
 463   if ((iBin >= 0) && (iBin+1 < fTRFbin)) {
 464     return fTRFsmp[iBin] + (fTRFsmp[iBin+1] - fTRFsmp[iBin])*dt;
 465   }
 466   else {
 467     return 0.0;
 468   }
 469
 470 }
 471
 472 //_____________________________________________________________________________
 473 Double_t AliTRDSimParam::CrossTalk(Double_t time) const
 474 {
 475   //
 476   // Applies the pad-pad capacitive cross talk
 477   //
 478
 479   Double_t rt   = (time - fTRFlo) / fTRFwid;
 480   Int_t    iBin = (Int_t) rt;
 481   Double_t dt   = rt - iBin;
 482   if ((iBin >= 0) && (iBin+1 < fTRFbin)) {
 483     return fCTsmp[iBin] + (fCTsmp[iBin+1] - fCTsmp[iBin])*dt;
 484   }
 485   else {
 486     return 0.0;
 487   }
 488
 489 }