TDPMjet/AliGenDPMjet.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
  17 // Generator using DPMJET as an external generator
  18 // The main DPMJET options are accessable for the user through this interface.
  19 // Uses the TDPMjet implementation of TGenerator.
  20
  21 #include <TDPMjet.h>
  22 #include <TRandom.h>
  23 #include <TArrayI.h>
  24 #include <TParticle.h>
  25 #include <TGraph.h>
  26 #include <TDatabasePDG.h>
  27 #include <TParticlePDG.h>
  28 #include <TParticleClassPDG.h>
  29 #include <TPDGCode.h>
  30 #include <TLorentzVector.h>
  31
  32 #include "AliGenDPMjet.h"
  33 #include "AliGenDPMjetEventHeader.h"
  34 #include "AliPythia.h"
  35 #include "AliRun.h"
  36 #include "AliDpmJetRndm.h"
  37
  38  ClassImp(AliGenDPMjet)
  39
  40
  41 //______________________________________________________________________________
  42 AliGenDPMjet::AliGenDPMjet()
  43                  :AliGenMC()
  44 {
  45 // Constructor
  46     fParticles = 0;
  47     fDPMjet = 0;
  48     AliDpmJetRndm::SetDpmJetRandom(GetRandom());
  49 }
  50
  51
  52 //______________________________________________________________________________
  53 AliGenDPMjet::AliGenDPMjet(Int_t npart)
  54     :AliGenMC(npart)
  55 {
  56 // Default PbPb collisions at 5. 5 TeV
  57 //
  58     fName = "DPMJET";
  59     fTitle= "Particle Generator using DPMJET";
  60
  61     SetBeamEnergy();
  62     SetEnergyCMS();
  63     SetTarget();
  64     SetProjectile();
  65     SetCentral();
  66     SetImpactParameterRange();
  67     SetBoostLHC();
  68
  69     fKeep       =  0;
  70     fDecaysOff  =  1;
  71     fEvaluate   =  0;
  72     fSelectAll  =  0;
  73     fFlavor     =  0;
  74     fSpectators =  1;
  75     fVertex.Set(3);
  76
  77     fParticles = new TClonesArray("TParticle",10000);
  78
  79     // Set random number generator
  80     fDPMjet = 0;
  81     // Instance AliPythia
  82     AliPythia::Instance();
  83     AliDpmJetRndm::SetDpmJetRandom(GetRandom());
  84 }
  85
  86 AliGenDPMjet::AliGenDPMjet(const AliGenDPMjet &/*Dpmjet*/)
  87 :AliGenMC()
  88 {
  89 }
  90
  91 //______________________________________________________________________________
  92 AliGenDPMjet::~AliGenDPMjet()
  93 {
  94 // Destructor
  95     delete fParticles;
  96 }
  97
  98
  99 //______________________________________________________________________________
 100 void AliGenDPMjet::Init()
 101 {
 102 // Initialization
 103
 104     SetMC(new TDPMjet(fAProjectile, fZProjectile, fATarget, fZTarget,
 105                       fBeamEn,fEnergyCMS));
 106
 107     fDPMjet=(TDPMjet*) fMCEvGen;
 108     //
 109     // **** Flag to force central production
 110     // fICentr=1. central production forced
 111     // fICentr<0 && fICentr>-100 -> bmin = fMinImpactParam, bmax = fMaxImpactParam
 112     // fICentr<-99 -> fraction of x-sec. = XSFRAC
 113     // fICentr=-1. -> evaporation/fzc suppressed
 114     // fICentr<-1. -> evaporation/fzc suppressed
 115     if (fAProjectile == 1 && fZProjectile == 1) fDPMjet->SetfIdp(1);
 116
 117     fDPMjet->SetfFCentr(fICentr);
 118     fDPMjet->SetbRange(fMinImpactParam,fMaxImpactParam);
 119
 120 //
 121 //  Initialize DPMjet
 122 //
 123     fDPMjet->Initialize();
 124     //if (fEvaluate) EvaluateCrossSections();
 125
 126     //  Initialize AliIonPDGCodes to define ion PDG codes
 127     /*AliIonPDGCodes *PDGcodes = new AliIonPDGCodes();
 128     PDGcodes->AddParticlesToPdgDataBase();
 129     PDGcodes->MapPDGGEant3Codes();*/
 130 }
 131
 132
 133 //______________________________________________________________________________
 134 void AliGenDPMjet::Generate()
 135 {
 136 // Generate one event
 137
 138   Float_t polar[3]    =   {0,0,0};
 139   Float_t origin[3]   =   {0,0,0};
 140   Float_t origin0[3]  =   {0,0,0};
 141   Float_t p[3], random[6];
 142   Float_t tof;
 143
 144 //  converts from mm/c to s
 145   const Float_t kconv = 0.001/2.999792458e8;
 146   Int_t nt  = 0;
 147   Int_t jev = 0;
 148   Int_t j, kf, ks, imo;
 149   kf = 0;
 150
 151   fTrials = 0;
 152   for (j = 0;j < 3; j++) origin0[j] = fOrigin[j];
 153   if(fVertexSmear == kPerEvent) {
 154       Float_t dv[3];
 155       dv[2] = 1.e10;
 156       while(TMath::Abs(dv[2])>fCutVertexZ*fOsigma[2]) {
 157           Rndm(random,6);
 158           for (j=0; j < 3; j++) {
 159               dv[j] = fOsigma[j]*TMath::Cos(2*random[2*j]*TMath::Pi())*
 160                   TMath::Sqrt(-2*TMath::Log(random[2*j+1]));
 161           }
 162       }
 163       for (j=0; j < 3; j++) origin0[j] += dv[j];
 164   }
 165
 166   while(1)
 167   {
 168 //    Generate one event
 169 // --------------------------------------------------------------------------
 170       fSpecn = 0;
 171       fSpecp = 0;
 172 // --------------------------------------------------------------------------
 173       fDPMjet->GenerateEvent();
 174       fTrials++;
 175
 176       fDPMjet->ImportParticles(fParticles,"All");
 177       if (fLHC) Boost();
 178
 179       // Temporaneo
 180       fGenImpPar = fDPMjet->GetBImpac();
 181
 182       Int_t np = fParticles->GetEntriesFast();
 183       printf("\n **************************************************%d\n",np);
 184       Int_t nc=0;
 185       if (np==0) continue;
 186       Int_t i;
 187       Int_t* newPos     = new Int_t[np];
 188       Int_t* pSelected  = new Int_t[np];
 189
 190       for (i = 0; i<np; i++) {
 191           newPos[i]    = i;
 192           pSelected[i] = 0;
 193       }
 194
 195 //      Get event vertex
 196
 197       //TParticle *iparticle = (TParticle*) fParticles->At(0);
 198       fVertex[0] = origin0[0];
 199       fVertex[1] = origin0[1];
 200       fVertex[2] = origin0[2];
 201       //for(int jj=0; jj<3; jj++) printf("      fEventVertex[%d] = %f\n",jj,fEventVertex[jj]);
 202
 203 //      First select parent particles
 204
 205       for (i = 0; i<np; i++) {
 206           TParticle *iparticle = (TParticle *) fParticles->At(i);
 207           //if(!iparticle) iparticle->Print("");
 208
 209 // Is this a parent particle ?
 210
 211           if (Stable(iparticle)) continue;
 212
 213           Bool_t  selected             =  kTRUE;
 214           Bool_t  hasSelectedDaughters =  kFALSE;
 215
 216           kf = iparticle->GetPdgCode();
 217           if (kf == 92) continue;
 218           ks = iparticle->GetStatusCode();
 219 // No initial state partons
 220           if (ks==21) continue;
 221
 222           if (!fSelectAll) selected = KinematicSelection(iparticle, 0) &&
 223                                SelectFlavor(kf);
 224           hasSelectedDaughters = DaughtersSelection(iparticle);
 225
 226 // Put particle on the stack if it is either selected or
 227 // it is the mother of at least one seleted particle
 228
 229           if (selected || hasSelectedDaughters) {
 230               nc++;
 231               pSelected[i] = 1;
 232           } // selected
 233       } // particle loop parents
 234
 235 // Now select the final state particles
 236
 237
 238       for (i=0; i<np; i++) {
 239           TParticle *iparticle = (TParticle *) fParticles->At(i);
 240           //if(!iparticle) printf("     i = %d -> iparticle==0\n",i);
 241
 242 // Is this a final state particle ?
 243
 244           if (!Stable(iparticle)) continue;
 245
 246           Bool_t  selected =  kTRUE;
 247           kf = iparticle->GetPdgCode();
 248           ks = iparticle->GetStatusCode();
 249
 250 // --------------------------------------------------------------------------
 251 // Count spectator neutrons and protons (ks == 13, 14)
 252           if(ks == 13 || ks == 14){
 253               if(kf == kNeutron) fSpecn += 1;
 254               if(kf == kProton)  fSpecp += 1;
 255           }
 256 // --------------------------------------------------------------------------
 257
 258           if (!fSelectAll) {
 259               selected = KinematicSelection(iparticle,0)&&SelectFlavor(kf);
 260               if (!fSpectators && selected) selected = (ks == 13 || ks == 14);
 261           }
 262
 263 // Put particle on the stack if selected
 264
 265           if (selected) {
 266               nc++;
 267               pSelected[i] = 1;
 268           } // selected
 269       } // particle loop final state
 270
 271 // Write particles to stack
 272
 273       for (i = 0; i<np; i++) {
 274           TParticle *  iparticle = (TParticle *) fParticles->At(i);
 275           Bool_t  hasMother   = (iparticle->GetFirstMother()>=0);
 276 //        Bool_t  hasDaughter = (iparticle->GetFirstDaughter()>=0);
 277
 278           if (pSelected[i]) {
 279
 280               kf   = iparticle->GetPdgCode();
 281               if(kf==99999) continue;
 282               ks   = iparticle->GetStatusCode();
 283
 284               p[0] = iparticle->Px();
 285               p[1] = iparticle->Py();
 286               p[2] = iparticle->Pz();
 287               origin[0] = origin0[0]+iparticle->Vx()/10;
 288               origin[1] = origin0[1]+iparticle->Vy()/10;
 289               origin[2] = origin0[2]+iparticle->Vz()/10;
 290               tof = kconv*iparticle->T();
 291
 292               imo = -1;
 293               TParticle* mother = 0;
 294               if (hasMother) {
 295                   imo = iparticle->GetFirstMother();
 296                   mother = (TParticle *) fParticles->At(imo);
 297                   imo = (mother->GetPdgCode() != 92) ? imo = newPos[imo] : -1;
 298               } // if has mother
 299
 300               // --- Nucleons and photons from nucleus evaporation
 301               //if(ks==-1 && (kf==2212 || kf==2112 || kf==22)) imo=-1;
 302
 303               // --- Offset added to nuclei, alpha particles, deuteron
 304               // --- and triton PDG codes (according to TGeant3 PDG codes)
 305               //if(ks==1000 || ks==1001) kf += 10000000;
 306               if(kf>10000) kf += 10000000;
 307
 308               if(kf>10000 || ks==1000 || ks==1001) printf(" kf = %d, ks = %d imo = %d \n", kf,ks,imo);
 309
 310
 311               Bool_t tFlag = (fTrackIt && (ks == 1));
 312
 313 /*            // --- Particle NOT to be tracked:
 314               // --- (1) chains from valence quark system (idhkk=99999)
 315               // --- (2) quark, diquarks and gluons (idhkk=1->8,...,idhkk=21)
 316               if(kf==99999 || kf==1 || kf==2 || kf==3 || kf==4 || kf==5 ||
 317                  kf==6 || kf==7 || kf==8 || kf==21 ||
 318                  kf==1103 || kf==2101 || kf==2103 || kf==2203 || kf==3101 ||
 319                  kf==3103 || kf==3201 || kf==3203 || kf==3303 || kf==4101 ||
 320                  kf==4103 || kf==4201 || kf==4203 || kf==4301 || kf==4303 ||
 321                  kf==4403 || kf==5101 || kf==5103 || kf==5201 || kf==5203 ||
 322                  kf==5301 || kf==5303 || kf==5401 || kf==5403 || kf==5503)
 323                  tFlag=kFALSE;
 324 */
 325               PushTrack(tFlag,imo,kf,p,origin,polar,tof,kPNoProcess,nt, 1., ks);
 326               KeepTrack(nt);
 327               newPos[i] = nt;
 328           } // if selected
 329       } // particle loop
 330       delete[] newPos;
 331       delete[] pSelected;
 332
 333       printf("\n I've put %i particles on the stack \n",nc);
 334       if (nc>0) {
 335           jev += nc;
 336           if (jev >= fNpart || fNpart == -1) {
 337               printf("\n Trials: %i %i %i\n",fTrials, fNpart, jev);
 338               break;
 339           }
 340           printf("\n Not breaking ### Trials: %i %i %i\n",fTrials, fNpart, jev);
 341       }
 342   } // event loop
 343   MakeHeader();
 344   SetHighWaterMark(nt);
 345 }
 346
 347
 348 //______________________________________________________________________________
 349 void AliGenDPMjet::KeepFullEvent()
 350 {
 351     fKeep=1;
 352 }
 353
 354
 355 //______________________________________________________________________________
 356 /*void AliGenDPMjet::EvaluateCrossSections()
 357 {
 358 //     Glauber Calculation of geometrical x-section
 359 //
 360     Float_t xTot       = 0.;          // barn
 361     Float_t xTotHard   = 0.;          // barn
 362     Float_t xPart      = 0.;          // barn
 363     Float_t xPartHard  = 0.;          // barn
 364     Float_t sigmaHard  = 0.1;         // mbarn
 365     Float_t bMin       = 0.;
 366     Float_t bMax       = fDPMjet->GetProjRadius()+fDPMjet->GetTargRadius();
 367     const Float_t kdib = 0.2;
 368     Int_t   kMax       = Int_t((bMax-bMin)/kdib)+1;
 369
 370
 371     printf("\n Projectile Radius (fm): %f \n",fDPMjet->GetProjRadius());
 372     printf("\n Target     Radius (fm): %f \n",fDPMjet->GetTargRadius());
 373     Int_t i;
 374     Float_t oldvalue= 0.;
 375
 376     Float_t* b   = new Float_t[kMax];
 377     Float_t* si1 = new Float_t[kMax];
 378     Float_t* si2 = new Float_t[kMax];
 379
 380     for (i = 0; i < kMax; i++)
 381     {
 382         Float_t xb  = bMin+i*kdib;
 383         Float_t ov;
 384         ov=fDPMjet->Profile(xb);
 385         // ATT!->Manca la x-sec anel. nucleone-nucleone
 386         Float_t gb  =  2.*0.01*fDPMjet->TMath::Pi()*kdib*xb*(1.-TMath::Exp(-fDPMjet->GetXSFrac()*ov));
 387         Float_t gbh =  2.*0.01*fDPMjet->TMath::Pi()*kdib*xb*sigmaHard*ov;
 388         xTot+=gb;
 389         xTotHard += gbh;
 390         if (xb > fMinImpactParam && xb < fMaxImpactParam)
 391         {
 392             xPart += gb;
 393             xPartHard += gbh;
 394         }
 395
 396         if(oldvalue) if ((xTot-oldvalue)/oldvalue<0.0001) break;
 397         oldvalue = xTot;
 398         printf("\n Total cross section (barn): %d %f %f \n",i, xb, xTot);
 399         printf("\n Hard  cross section (barn): %d %f %f \n\n",i, xb, xTotHard);
 400         if (i>0) {
 401             si1[i] = gb/kdib;
 402             si2[i] = gbh/gb;
 403             b[i]  = xb;
 404         }
 405     }
 406
 407     printf("\n Total cross section (barn): %f \n",xTot);
 408     printf("\n Hard  cross section (barn): %f \n \n",xTotHard);
 409     printf("\n Partial       cross section (barn): %f %f \n",xPart, xPart/xTot*100.);
 410     printf("\n Partial  hard cross section (barn): %f %f \n",xPartHard, xPartHard/xTotHard*100.);
 411
 412 //  Store result as a graph
 413     b[0] = 0;
 414     si1[0] = 0;
 415     si2[0]=si2[1];
 416
 417     fDsigmaDb  = new TGraph(i, b, si1);
 418     fDnDb      = new TGraph(i, b, si2);
 419 }*/
 420
 421
 422 //______________________________________________________________________________
 423 Bool_t AliGenDPMjet::DaughtersSelection(TParticle* iparticle)
 424 {
 425 //
 426 // Looks recursively if one of the daughters has been selected
 427 //
 428 //    printf("\n Consider daughters %d:",iparticle->GetPdgCode());
 429     Int_t imin = -1;
 430     Int_t imax = -1;
 431     Int_t i;
 432     Bool_t hasDaughters = (iparticle->GetFirstDaughter() >=0);
 433     Bool_t selected = kFALSE;
 434     if (hasDaughters) {
 435         imin = iparticle->GetFirstDaughter();
 436         imax = iparticle->GetLastDaughter();
 437         for (i = imin; i <= imax; i++){
 438             TParticle *  jparticle = (TParticle *) fParticles->At(i);
 439             Int_t ip = jparticle->GetPdgCode();
 440             if (KinematicSelection(jparticle,0)&&SelectFlavor(ip)) {
 441                 selected=kTRUE; break;
 442             }
 443             if (DaughtersSelection(jparticle)) {selected=kTRUE; break; }
 444         }
 445     } else {
 446         return kFALSE;
 447     }
 448     return selected;
 449 }
 450
 451
 452
 453 //______________________________________________________________________________
 454 Bool_t AliGenDPMjet::SelectFlavor(Int_t pid)
 455 {
 456 // Select flavor of particle
 457 // 0: all
 458 // 4: charm and beauty
 459 // 5: beauty
 460     Bool_t res = 0;
 461
 462     if (fFlavor == 0) {
 463         res = kTRUE;
 464     } else {
 465         Int_t ifl = TMath::Abs(pid/100);
 466         if (ifl > 10) ifl/=10;
 467         res = (fFlavor == ifl);
 468     }
 469 //
 470 //  This part if gamma writing is inhibited
 471     if (fNoGammas)
 472         res = res && (pid != kGamma && pid != kPi0);
 473 //
 474     return res;
 475 }
 476
 477 //______________________________________________________________________________
 478 Bool_t AliGenDPMjet::Stable(TParticle*  particle)
 479 {
 480 // Return true for a stable particle
 481 //
 482
 483 //    if (particle->GetFirstDaughter() < 0 ) return kTRUE;
 484     if (particle->GetStatusCode() == 1) return kTRUE;
 485     else return kFALSE;
 486
 487 }
 488
 489
 490
 491 //______________________________________________________________________________
 492 /*void AliGenDPMjet::Boost(TClonesArray* particles)
 493 {
 494 //
 495 // Boost cms into LHC lab frame
 496 //
 497     Double_t dy    = - 0.5 * TMath::Log(Double_t(fZProjectile) * Double_t(fATarget) /
 498                                       (Double_t(fZTarget)    * Double_t(fAProjectile)));
 499     Double_t beta  = TMath::TanH(dy);
 500     Double_t gamma = 1./TMath::Sqrt(1.-beta*beta);
 501     Double_t gb    = gamma * beta;
 502
 503     printf("\n Boosting particles to lab frame %f %f %f", dy, beta, gamma);
 504
 505     Int_t i;
 506     Int_t np = particles->GetEntriesFast();
 507     for (i = 0; i < np; i++)
 508     {
 509         TParticle* iparticle = (TParticle*) fParticles->At(i);
 510
 511         Double_t e   = iparticle->Energy();
 512         Double_t px  = iparticle->Px();
 513         Double_t py  = iparticle->Py();
 514         Double_t pz  = iparticle->Pz();
 515
 516         Double_t eb  = gamma * e -      gb * pz;
 517         Double_t pzb =   -gb * e +   gamma * pz;
 518
 519         iparticle->SetMomentum(px, py, pzb, eb);
 520     }
 521 }*/
 522
 523
 524
 525 //______________________________________________________________________________
 526 void AliGenDPMjet::MakeHeader()
 527 {
 528 // Builds the event header, to be called after each event
 529     AliGenEventHeader* header = new AliGenDPMjetEventHeader("DPMJET");
 530     ((AliGenDPMjetEventHeader*) header)->SetNProduced(fDPMjet->GetNumStablePc());
 531     ((AliGenDPMjetEventHeader*) header)->SetImpactParameter(fDPMjet->GetBImpac());
 532     ((AliGenDPMjetEventHeader*) header)->SetTotalEnergy(fDPMjet->GetTotEnergy());
 533 //    ((AliGenDPMjetEventHeader*) header)->SetWounded(fDPMjet->GetProjWounded(),
 534 //                                                  fDPMjet->GetTargWounded());
 535     ((AliGenDPMjetEventHeader*) header)->SetParticipants(fDPMjet->GetfIp(),
 536                                                          fDPMjet->GetfIt());
 537     /*((AliGenDPMjetEventHeader*) header)->SetCollisions(fDPMjet->GetN0(),
 538                                                        fDPMjet->GetN01(),
 539                                                        fDPMjet->GetN10(),
 540                                                        fDPMjet->GetN11());*/
 541     ((AliGenDPMjetEventHeader*) header)->SetSpectators(fSpecn, fSpecp);
 542
 543 // Bookkeeping for kinematic bias
 544     ((AliGenDPMjetEventHeader*) header)->SetTrials(fTrials);
 545 // Event Vertex
 546     header->SetPrimaryVertex(fVertex);
 547     gAlice->SetGenEventHeader(header);
 548 }
 549
 550
 551
 552 //______________________________________________________________________________
 553 AliGenDPMjet& AliGenDPMjet::operator=(const  AliGenDPMjet& /*rhs*/)
 554 {
 555 // Assignment operator
 556     return *this;
 557 }
 558
 559
 560
 561 //______________________________________________________________________________