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
  33 ClassImp(AliTRDSimParam)
  34
  35 AliTRDSimParam *AliTRDSimParam::fgInstance   = 0;
  36 Bool_t          AliTRDSimParam::fgTerminated = kFALSE;
  37
  38 //_ singleton implementation __________________________________________________
  39 AliTRDSimParam* AliTRDSimParam::Instance()
  40 {
  41   //
  42   // Singleton implementation
  43   // Returns an instance of this class, it is created if neccessary
  44   //
  45
  46   if (fgTerminated != kFALSE) {
  47     return 0;
  48   }
  49
  50   if (fgInstance == 0) {
  51     fgInstance = new AliTRDSimParam();
  52   }
  53
  54   return fgInstance;
  55
  56 }
  57
  58 //_ singleton implementation __________________________________________________
  59 void AliTRDSimParam::Terminate()
  60 {
  61   //
  62   // Singleton implementation
  63   // Deletes the instance of this class and sets the terminated flag,
  64   // instances cannot be requested anymore
  65   // This function can be called several times.
  66   //
  67
  68   fgTerminated = kTRUE;
  69
  70   if (fgInstance != 0) {
  71     delete fgInstance;
  72     fgInstance = 0;
  73   }
  74
  75 }
  76
  77 //_____________________________________________________________________________
  78 AliTRDSimParam::AliTRDSimParam()
  79   :TObject()
  80   ,fGasGain(0.0)
  81   ,fNoise(0.0)
  82   ,fChipGain(0.0)
  83   ,fADCoutRange(0.0)
  84   ,fADCinRange(0.0)
  85   ,fADCthreshold(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   ,fAnodeWireOffset(0.0)
  99   ,fPadCoupling(0.0)
 100   ,fTimeCoupling(0.0)
 101   ,fTimeStructOn(kFALSE)
 102   ,fPRFOn(kFALSE)
 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   fADCthreshold      =    3;
 126   // Go back to 0 again, just to be consistent with reconstruction
 127   fADCbaseline       =    0;
 128   //fADCbaseline       =   10;
 129
 130   // Diffusion on
 131   fDiffusionOn       = kTRUE;
 132
 133   // Propability for electron attachment
 134   fElAttachOn        = kFALSE;
 135   fElAttachProp      = 0.0;
 136
 137   // The time response function
 138   fTRFOn             = kTRUE;
 139
 140   // The cross talk
 141   fCTOn              = kTRUE;
 142
 143   // The pad coupling factor
 144   // Use 0.46, instead of the theroetical value 0.3, since it reproduces better
 145   // the test beam data, even tough it is not understood why.
 146   fPadCoupling       = 0.46;
 147
 148   // The time coupling factor (same number as for the TPC)
 149   fTimeCoupling      = 0.4;
 150
 151   // Distance of first Anode wire from first pad edge
 152   fAnodeWireOffset   = 0.25;
 153
 154   // Use drift time maps
 155   fTimeStructOn      = kTRUE;
 156
 157   // The pad response function
 158   fPRFOn             = kTRUE;
 159
 160   ReInit();
 161
 162 }
 163
 164 //_____________________________________________________________________________
 165 AliTRDSimParam::~AliTRDSimParam()
 166 {
 167   //
 168   // Destructor
 169   //
 170
 171   if (fTRFsmp) {
 172     delete [] fTRFsmp;
 173     fTRFsmp = 0;
 174   }
 175
 176   if (fCTsmp) {
 177     delete [] fCTsmp;
 178     fCTsmp  = 0;
 179   }
 180
 181 }
 182
 183 //_____________________________________________________________________________
 184 AliTRDSimParam::AliTRDSimParam(const AliTRDSimParam &p)
 185   :TObject(p)
 186   ,fGasGain(p.fGasGain)
 187   ,fNoise(p.fNoise)
 188   ,fChipGain(p.fChipGain)
 189   ,fADCoutRange(p.fADCoutRange)
 190   ,fADCinRange(p.fADCinRange)
 191   ,fADCthreshold(p.fADCthreshold)
 192   ,fADCbaseline(p.fADCbaseline)
 193   ,fDiffusionOn(p.fDiffusionOn)
 194   ,fElAttachOn(p.fElAttachOn)
 195   ,fElAttachProp(p.fElAttachProp)
 196   ,fTRFOn(p.fTRFOn)
 197   ,fTRFsmp(0)
 198   ,fTRFbin(p.fTRFbin)
 199   ,fTRFlo(p.fTRFlo)
 200   ,fTRFhi(p.fTRFhi)
 201   ,fTRFwid(p.fTRFwid)
 202   ,fCTOn(p.fCTOn)
 203   ,fCTsmp(0)
 204   ,fAnodeWireOffset(p.fAnodeWireOffset)
 205   ,fPadCoupling(p.fPadCoupling)
 206   ,fTimeCoupling(p.fTimeCoupling)
 207   ,fTimeStructOn(p.fTimeStructOn)
 208   ,fPRFOn(p.fPRFOn)
 209 {
 210   //
 211   // Copy constructor
 212   //
 213
 214   Int_t iBin = 0;
 215
 216   if (((AliTRDSimParam &) p).fTRFsmp) {
 217     delete [] ((AliTRDSimParam &) p).fTRFsmp;
 218   }
 219   ((AliTRDSimParam &) p).fTRFsmp = new Float_t[fTRFbin];
 220   for (iBin = 0; iBin < fTRFbin; iBin++) {
 221     ((AliTRDSimParam &) p).fTRFsmp[iBin] = fTRFsmp[iBin];
 222   }
 223
 224   if (((AliTRDSimParam &) p).fCTsmp) {
 225     delete [] ((AliTRDSimParam &) p).fCTsmp;
 226   }
 227   ((AliTRDSimParam &) p).fCTsmp  = new Float_t[fTRFbin];
 228   for (iBin = 0; iBin < fTRFbin; iBin++) {
 229     ((AliTRDSimParam &) p).fCTsmp[iBin] = fCTsmp[iBin];
 230   }
 231
 232 }
 233
 234 //_____________________________________________________________________________
 235 AliTRDSimParam &AliTRDSimParam::operator=(const AliTRDSimParam &p)
 236 {
 237   //
 238   // Assignment operator
 239   //
 240
 241   if (this != &p) {
 242     ((AliTRDSimParam &) p).Copy(*this);
 243   }
 244
 245   return *this;
 246
 247 }
 248
 249 //_____________________________________________________________________________
 250 void AliTRDSimParam::Copy(TObject &p) const
 251 {
 252   //
 253   // Copy function
 254   //
 255
 256   AliTRDSimParam *target = dynamic_cast<AliTRDSimParam *> (&p);
 257   if (!target) {
 258     return;
 259   }
 260
 261   target->fGasGain            = fGasGain;
 262   target->fNoise              = fNoise;
 263   target->fChipGain           = fChipGain;
 264   target->fADCoutRange        = fADCoutRange;
 265   target->fADCinRange         = fADCinRange;
 266   target->fADCthreshold       = fADCthreshold;
 267   target->fADCbaseline        = fADCbaseline;
 268   target->fDiffusionOn        = fDiffusionOn;
 269   target->fElAttachOn         = fElAttachOn;
 270   target->fElAttachProp       = fElAttachProp;
 271   target->fTRFOn              = fTRFOn;
 272   target->fTRFbin             = fTRFbin;
 273   target->fTRFlo              = fTRFlo;
 274   target->fTRFhi              = fTRFhi;
 275   target->fTRFwid             = fTRFwid;
 276   target->fCTOn               = fCTOn;
 277   target->fAnodeWireOffset    = fAnodeWireOffset;
 278   target->fPadCoupling        = fPadCoupling;
 279   target->fTimeCoupling       = fTimeCoupling;
 280   target->fPRFOn              = fPRFOn;
 281
 282   if (target->fTRFsmp) {
 283     delete[] target->fTRFsmp;
 284   }
 285   target->fTRFsmp = new Float_t[fTRFbin];
 286   for (Int_t iBin = 0; iBin < fTRFbin; iBin++) {
 287     target->fTRFsmp[iBin] = fTRFsmp[iBin];
 288   }
 289
 290   if (target->fCTsmp) {
 291     delete[] target->fCTsmp;
 292   }
 293   target->fCTsmp  = new Float_t[fTRFbin];
 294   for (Int_t iBin = 0; iBin < fTRFbin; iBin++) {
 295     target->fCTsmp[iBin]  = fCTsmp[iBin];
 296   }
 297
 298 }
 299
 300 //_____________________________________________________________________________
 301 void AliTRDSimParam::ReInit()
 302 {
 303   //
 304   // Reinitializes the parameter class after a change
 305   //
 306
 307   // The range and the binwidth for the sampled TRF
 308   fTRFbin = 200;
 309   // Start 0.2 mus before the signal
 310   fTRFlo  = -0.4;
 311   // End the maximum drift time after the signal
 312   fTRFhi  =  3.58;
 313   fTRFwid = (fTRFhi - fTRFlo) / ((Float_t) fTRFbin);
 314
 315   // Create the sampled TRF
 316   SampleTRF();
 317
 318 }
 319
 320 //_____________________________________________________________________________
 321 void AliTRDSimParam::SampleTRF()
 322 {
 323   //
 324   // Samples the new time response function.
 325   // From Antons measurements with Fe55 source, adjusted by C. Lippmann.
 326   // time bins are -0.4, -0.38, -0.36, ...., 3.54, 3.56, 3.58 microseconds
 327   //
 328
 329   const Int_t kNpasa     = 200;  // kNpasa should be equal to fTRFbin!
 330
 331   Float_t signal[kNpasa]={ 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000
 332                          , 0.0002, 0.0007, 0.0026, 0.0089, 0.0253, 0.0612, 0.1319
 333                          , 0.2416, 0.3913, 0.5609, 0.7295, 0.8662, 0.9581, 1.0000
 334                          , 0.9990, 0.9611, 0.8995, 0.8269, 0.7495, 0.6714, 0.5987
 335                          , 0.5334, 0.4756, 0.4249, 0.3811, 0.3433, 0.3110, 0.2837
 336                          , 0.2607, 0.2409, 0.2243, 0.2099, 0.1974, 0.1868, 0.1776
 337                          , 0.1695, 0.1627, 0.1566, 0.1509, 0.1457, 0.1407, 0.1362
 338                          , 0.1317, 0.1274, 0.1233, 0.1196, 0.1162, 0.1131, 0.1102
 339                          , 0.1075, 0.1051, 0.1026, 0.1004, 0.0979, 0.0956, 0.0934
 340                          , 0.0912, 0.0892, 0.0875, 0.0858, 0.0843, 0.0829, 0.0815
 341                          , 0.0799, 0.0786, 0.0772, 0.0757, 0.0741, 0.0729, 0.0718
 342                          , 0.0706, 0.0692, 0.0680, 0.0669, 0.0655, 0.0643, 0.0630
 343                          , 0.0618, 0.0607, 0.0596, 0.0587, 0.0576, 0.0568, 0.0558
 344                          , 0.0550, 0.0541, 0.0531, 0.0522, 0.0513, 0.0505, 0.0497
 345                          , 0.0490, 0.0484, 0.0474, 0.0465, 0.0457, 0.0449, 0.0441
 346                          , 0.0433, 0.0425, 0.0417, 0.0410, 0.0402, 0.0395, 0.0388
 347                          , 0.0381, 0.0374, 0.0368, 0.0361, 0.0354, 0.0348, 0.0342
 348                          , 0.0336, 0.0330, 0.0324, 0.0318, 0.0312, 0.0306, 0.0301
 349                          , 0.0296, 0.0290, 0.0285, 0.0280, 0.0275, 0.0270, 0.0265
 350                          , 0.0260, 0.0256, 0.0251, 0.0246, 0.0242, 0.0238, 0.0233
 351                          , 0.0229, 0.0225, 0.0221, 0.0217, 0.0213, 0.0209, 0.0206
 352                          , 0.0202, 0.0198, 0.0195, 0.0191, 0.0188, 0.0184, 0.0181
 353                          , 0.0178, 0.0175, 0.0171, 0.0168, 0.0165, 0.0162, 0.0159
 354                          , 0.0157, 0.0154, 0.0151, 0.0148, 0.0146, 0.0143, 0.0140
 355                          , 0.0138, 0.0135, 0.0133, 0.0131, 0.0128, 0.0126, 0.0124
 356                          , 0.0121, 0.0119, 0.0120, 0.0115, 0.0113, 0.0111, 0.0109
 357                          , 0.0107, 0.0105, 0.0103, 0.0101, 0.0100, 0.0098, 0.0096
 358                          , 0.0094, 0.0092, 0.0091, 0.0089, 0.0088, 0.0086, 0.0084
 359                          , 0.0083, 0.0081, 0.0080, 0.0078 };
 360
 361         // Andronic & Bercuci parametrization
 362         // define new TRF parametrization
 363                 // normalizing constant to Fe signal
 364         const Float_t k1=1.055;
 365         // time constants
 366         const Float_t t1=0.04;
 367         const Float_t t2=.9;
 368         // the relative fraction of the long component
 369         const Float_t k2=.15;
 370         // time offset for Fe
 371         const Float_t t0=-.29;
 372         Float_t x = t0; Int_t index;
 373         for(int i=0; i<kNpasa; i++) signal[i] = 0.;
 374   for(int i=0; i<kNpasa; i++){
 375                 index = i+6;
 376                 if(index >= kNpasa) break;
 377                 x += .02;
 378                 signal[index]=k1*(pow((x-t0)/t1, 2.5)*(exp(-(x-t0)/t1))+k2*exp(-(x-t0)/t2));
 379         }
 380
 381         Float_t xtalk[kNpasa];
 382
 383   // With undershoot, positive peak corresponds to ~3% of the main signal:
 384   for (Int_t ipasa = 3; ipasa < kNpasa; ipasa++) {
 385     xtalk[ipasa] = 0.2 * (signal[ipasa-2] - signal[ipasa-3]);
 386   }
 387
 388   xtalk[0]  = 0.0;
 389   xtalk[1]  = 0.0;
 390   xtalk[2]  = 0.0;
 391
 392   signal[0] = 0.0;
 393   signal[1] = 0.0;
 394   signal[2] = 0.0;
 395
 396   if (fTRFsmp) {
 397     delete [] fTRFsmp;
 398   }
 399   fTRFsmp = new Float_t[fTRFbin];
 400
 401   if (fCTsmp)  {
 402     delete [] fCTsmp;
 403   }
 404   fCTsmp  = new Float_t[fTRFbin];
 405
 406   for (Int_t iBin = 0; iBin < fTRFbin; iBin++) {
 407     fTRFsmp[iBin] = signal[iBin];
 408     fCTsmp[iBin]  = xtalk[iBin];
 409   }
 410
 411 }
 412
 413 //_____________________________________________________________________________
 414 Double_t AliTRDSimParam::TimeResponse(Double_t time) const
 415 {
 416   //
 417   // Applies the preamp shaper time response
 418   // (We assume a signal rise time of 0.2us = fTRFlo/2.
 419   //
 420
 421   Int_t iBin = ((Int_t) ((time - fTRFlo/2.0) / fTRFwid));
 422   if ((iBin >=       0) &&
 423       (iBin <  fTRFbin)) {
 424     return fTRFsmp[iBin];
 425   }
 426   else {
 427     return 0.0;
 428   }
 429
 430 }
 431
 432 //_____________________________________________________________________________
 433 Double_t AliTRDSimParam::CrossTalk(Double_t time) const
 434 {
 435   //
 436   // Applies the pad-pad capacitive cross talk
 437   //
 438
 439   Int_t iBin = ((Int_t) ((time - fTRFlo) / fTRFwid));
 440   if ((iBin >=       0) &&
 441       (iBin <  fTRFbin)) {
 442     return fCTsmp[iBin];
 443   }
 444   else {
 445     return 0.0;
 446   }
 447
 448 }