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| 1 | + |
| 2 | +#include "Pythia8/Pythia.h" |
| 3 | +#include "Pythia8/HeavyIons.h" |
| 4 | +#include "FairGenerator.h" |
| 5 | +#include "FairPrimaryGenerator.h" |
| 6 | +#include "Generators/GeneratorPythia8.h" |
| 7 | +#include "TRandom3.h" |
| 8 | +#include "TParticlePDG.h" |
| 9 | +#include "TDatabasePDG.h" |
| 10 | +#include "CCDB/BasicCCDBManager.h" |
| 11 | +#include "TH1F.h" |
| 12 | +#include "TH1D.h" |
| 13 | + |
| 14 | +#include <map> |
| 15 | +#include <unordered_set> |
| 16 | + |
| 17 | +class GeneratorPythia8SyntheFlowXi : public o2::eventgen::GeneratorPythia8 |
| 18 | +{ |
| 19 | +public: |
| 20 | + /// Constructor |
| 21 | + GeneratorPythia8SyntheFlowXi() { |
| 22 | + lutGen = new o2::eventgen::FlowMapper(); |
| 23 | + |
| 24 | + // -------- CONFIGURE SYNTHETIC FLOW ------------ |
| 25 | + // establish connection to ccdb |
| 26 | + o2::ccdb::CcdbApi ccdb_api; |
| 27 | + ccdb_api.init("https://alice-ccdb.cern.ch"); |
| 28 | + |
| 29 | + // config was placed at midpoint of run 544122, retrieve that |
| 30 | + std::map<string, string> metadataRCT, headers; |
| 31 | + headers = ccdb_api.retrieveHeaders("RCT/Info/RunInformation/544122", metadataRCT, -1); |
| 32 | + int64_t tsSOR = atol(headers["SOR"].c_str()); |
| 33 | + int64_t tsEOR = atol(headers["EOR"].c_str()); |
| 34 | + int64_t midRun = 0.5*tsSOR+0.5*tsEOR; |
| 35 | + |
| 36 | + map<string, string> metadata; // can be empty |
| 37 | + auto list = ccdb_api.retrieveFromTFileAny<TList>("Users/d/ddobrigk/syntheflow", metadata, midRun); |
| 38 | + |
| 39 | + TH1D *hv2vspT = (TH1D*) list->FindObject("hFlowVsPt_ins1116150_v1_Table_1"); |
| 40 | + TH1D *heccvsb = (TH1D*) list->FindObject("hEccentricityVsB"); |
| 41 | + |
| 42 | + cout<<"Generating LUT for flow test"<<endl; |
| 43 | + lutGen->CreateLUT(hv2vspT, heccvsb); |
| 44 | + cout<<"Finished creating LUT!"<<endl; |
| 45 | + // -------- END CONFIGURE SYNTHETIC FLOW ------------ |
| 46 | + |
| 47 | + genMinPt=0.0; |
| 48 | + genMaxPt=20.0; |
| 49 | + genminY=-1.5; |
| 50 | + genmaxY=1.5; |
| 51 | + genminEta=-1.5; |
| 52 | + genmaxEta=1.5; |
| 53 | + |
| 54 | + pdg=0; |
| 55 | + E=0; |
| 56 | + px=0; |
| 57 | + py=0; |
| 58 | + pz=0; |
| 59 | + p=0; |
| 60 | + y=0; |
| 61 | + eta=0; |
| 62 | + xProd=0; |
| 63 | + yProd=0; |
| 64 | + zProd=0; |
| 65 | + xProd=0.; yProd=0.; zProd=0.; |
| 66 | + |
| 67 | + fLVHelper = std::make_unique<TLorentzVector>(); |
| 68 | + |
| 69 | + fSpectrumXi = std::make_unique<TF1>("fSpectrumXi", this, &GeneratorPythia8ExtraStrangeness::boltzPlusPower, 0., genMaxPt, 5, "GeneratorPythia8ExtraStrangeness", "boltzPlusPower"); |
| 70 | + |
| 71 | + fSpectrumXi->FixParameter(0, 1.32171); |
| 72 | + fSpectrumXi->FixParameter(1, 4.84e-1); |
| 73 | + fSpectrumXi->FixParameter(2, 111.9); |
| 74 | + fSpectrumXi->FixParameter(3, -2.56511e+00); |
| 75 | + fSpectrumXi->FixParameter(4, 1.14011e-04); |
| 76 | + |
| 77 | + fSpectrumOm = std::make_unique<TF1>("fSpectrumOm", this, &GeneratorPythia8ExtraStrangeness::boltzPlusPower, 0., genMaxPt, 5, "GeneratorPythia8ExtraStrangeness", "boltzPlusPower"); |
| 78 | + |
| 79 | + fSpectrumOm->FixParameter(0, 1.67245e+00); |
| 80 | + fSpectrumOm->FixParameter(1, 5.18174e-01); |
| 81 | + fSpectrumOm->FixParameter(2, 1.73747e+01); |
| 82 | + fSpectrumOm->FixParameter(3, -2.56681e+00); |
| 83 | + fSpectrumOm->FixParameter(4, 1.87513e-04); |
| 84 | + } |
| 85 | + |
| 86 | + /// Destructor |
| 87 | + ~GeneratorPythia8SyntheFlowXi() = default; |
| 88 | + |
| 89 | + Double_t y2eta(Double_t pt, Double_t mass, Double_t y){ |
| 90 | + Double_t mt = TMath::Sqrt(mass * mass + pt * pt); |
| 91 | + return TMath::ASinH(mt / pt * TMath::SinH(y)); |
| 92 | + } |
| 93 | + |
| 94 | + /// set 4-momentum |
| 95 | + void set4momentum(double input_px, double input_py, double input_pz){ |
| 96 | + px = input_px; |
| 97 | + py = input_py; |
| 98 | + pz = input_pz; |
| 99 | + E = sqrt( m*m+px*px+py*py+pz*pz ); |
| 100 | + fourMomentum.px(px); |
| 101 | + fourMomentum.py(py); |
| 102 | + fourMomentum.pz(pz); |
| 103 | + fourMomentum.e(E); |
| 104 | + p = sqrt( px*px+py*py+pz*pz ); |
| 105 | + y = 0.5*log( (E+pz)/(E-pz) ); |
| 106 | + eta = 0.5*log( (p+pz)/(p-pz) ); |
| 107 | + } |
| 108 | + |
| 109 | + //__________________________________________________________________ |
| 110 | + Pythia8::Particle createParticle(){ |
| 111 | + //std::cout << "createParticle() mass " << m << " pdgCode " << pdg << std::endl; |
| 112 | + Pythia8::Particle myparticle; |
| 113 | + myparticle.id(pdg); |
| 114 | + myparticle.status(11); |
| 115 | + myparticle.px(px); |
| 116 | + myparticle.py(py); |
| 117 | + myparticle.pz(pz); |
| 118 | + myparticle.e(E); |
| 119 | + myparticle.m(m); |
| 120 | + myparticle.xProd(xProd); |
| 121 | + myparticle.yProd(yProd); |
| 122 | + myparticle.zProd(zProd); |
| 123 | + |
| 124 | + return myparticle; |
| 125 | + } |
| 126 | + |
| 127 | + //_________________________________________________________________________________ |
| 128 | + /// generate uniform eta and uniform momentum |
| 129 | + void genSpectraMomentumEtaXi(double minP, double maxP, double minY, double maxY){ |
| 130 | + // random generator |
| 131 | + std::unique_ptr<TRandom3> ranGenerator { new TRandom3() }; |
| 132 | + ranGenerator->SetSeed(0); |
| 133 | + |
| 134 | + // generate transverse momentum |
| 135 | + const double gen_pT = fSpectrumXi->GetRandom(genMinPt,genMaxPt); |
| 136 | + |
| 137 | + //Actually could be something else without loss of generality but okay |
| 138 | + const double gen_phi = ranGenerator->Uniform(0,2*TMath::Pi()); |
| 139 | + |
| 140 | + // sample flat in rapidity, calculate eta |
| 141 | + Double_t gen_Y=10, gen_eta=10; |
| 142 | + |
| 143 | + while( gen_eta>genmaxEta || gen_eta<genminEta ){ |
| 144 | + gen_Y = ranGenerator->Uniform(minY,maxY); |
| 145 | + //(Double_t pt, Double_t mass, Double_t y) |
| 146 | + gen_eta = y2eta(gen_pT, m, gen_Y); |
| 147 | + } |
| 148 | + |
| 149 | + fLVHelper->SetPtEtaPhiM(gen_pT, gen_eta, gen_phi, m); |
| 150 | + set4momentum(fLVHelper->Px(),fLVHelper->Py(),fLVHelper->Pz()); |
| 151 | + } |
| 152 | + |
| 153 | + //_________________________________________________________________________________ |
| 154 | + /// generate uniform eta and uniform momentum |
| 155 | + void genSpectraMomentumEtaOm(double minP, double maxP, double minY, double maxY){ |
| 156 | + // random generator |
| 157 | + std::unique_ptr<TRandom3> ranGenerator { new TRandom3() }; |
| 158 | + ranGenerator->SetSeed(0); |
| 159 | + |
| 160 | + // generate transverse momentum |
| 161 | + const double gen_pT = fSpectrumOm->GetRandom(genMinPt,genMaxPt); |
| 162 | + |
| 163 | + //Actually could be something else without loss of generality but okay |
| 164 | + const double gen_phi = ranGenerator->Uniform(0,2*TMath::Pi()); |
| 165 | + |
| 166 | + // sample flat in rapidity, calculate eta |
| 167 | + Double_t gen_Y=10, gen_eta=10; |
| 168 | + |
| 169 | + while( gen_eta>genmaxEta || gen_eta<genminEta ){ |
| 170 | + gen_Y = ranGenerator->Uniform(minY,maxY); |
| 171 | + //(Double_t pt, Double_t mass, Double_t y) |
| 172 | + gen_eta = y2eta(gen_pT, m, gen_Y); |
| 173 | + } |
| 174 | + |
| 175 | + fLVHelper->SetPtEtaPhiM(gen_pT, gen_eta, gen_phi, m); |
| 176 | + set4momentum(fLVHelper->Px(),fLVHelper->Py(),fLVHelper->Pz()); |
| 177 | + } |
| 178 | + |
| 179 | + //_________________________________________________________________________________ |
| 180 | + /// shape function |
| 181 | + Double_t boltzPlusPower(const Double_t *x, const Double_t *p) |
| 182 | + { |
| 183 | + // a plain parametrization. not meant to be physics worthy. |
| 184 | + // adjusted to match preliminary 5 TeV shape. |
| 185 | + |
| 186 | + Double_t pt = x[0]; |
| 187 | + Double_t mass = p[0]; |
| 188 | + Double_t mt = TMath::Sqrt(pt * pt + mass * mass); |
| 189 | + Double_t T = p[1]; |
| 190 | + Double_t norm = p[2]; |
| 191 | + |
| 192 | + Double_t lowptpart = mt * TMath::Exp(-mt / T); |
| 193 | + Double_t highptpart = p[4]*TMath::Power(x[0], p[3]); |
| 194 | + |
| 195 | + Double_t mixup = 1./(1.+TMath::Exp((x[0]-4.5)/.1)); |
| 196 | + |
| 197 | + //return pt * norm * (mixup * mt * TMath::Exp(-mt / T) + (1.-mixup)*highptpart) ; |
| 198 | + return pt * norm * (mt * TMath::Exp(-mt / T) + (1.-mixup)*highptpart) ; |
| 199 | + } |
| 200 | + |
| 201 | + //__________________________________________________________________ |
| 202 | + Bool_t generateEvent() override { |
| 203 | + |
| 204 | + // Generate PYTHIA event |
| 205 | + Bool_t lPythiaOK = kFALSE; |
| 206 | + while (!lPythiaOK){ |
| 207 | + lPythiaOK = mPythia.next(); |
| 208 | + } |
| 209 | + |
| 210 | + //+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 211 | + // add extra xi/omega content |
| 212 | + // characterise event |
| 213 | + Long_t nParticles = mPythia.event.size(); |
| 214 | + Long_t nChargedParticlesAtMidRap = 0; |
| 215 | + Long_t nPionsAtMidRap = 0; |
| 216 | + for ( Long_t j=0; j < nParticles; j++ ) { |
| 217 | + Int_t pypid = mPythia.event[j].id(); |
| 218 | + Float_t pyrap = mPythia.event[j].y(); |
| 219 | + Float_t pyeta = mPythia.event[j].eta(); |
| 220 | + |
| 221 | + // final only |
| 222 | + if (!mPythia.event[j].isFinal()) continue; |
| 223 | + |
| 224 | + if ( TMath::Abs(pyrap) < 0.5 && TMath::Abs(pypid)==211 ) nPionsAtMidRap++; |
| 225 | + if ( TMath::Abs(pyeta) < 0.5 && TMath::Abs(mPythia.event[j].charge())>1e-5 ) nChargedParticlesAtMidRap++; |
| 226 | + } |
| 227 | + |
| 228 | + // now we have the multiplicity |
| 229 | + //+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 230 | + // XI ABUNDANCE FIX |
| 231 | + //Adjust relative abundance of multi-strange particles by injecting some |
| 232 | + Double_t lExpectedXiToPion = TMath::Max(4.74929e-03 - 4.08255e-03*TMath::Exp(-nChargedParticlesAtMidRap/4.76660e+00) - 0.00211334,0.); |
| 233 | + Double_t lExpectedXi = 5.0*nPionsAtMidRap*lExpectedXiToPion; // extra rich, factor 5 |
| 234 | + Int_t lXiYield = gRandom->Poisson(3*lExpectedXi); //factor 3: fix the rapidity acceptance |
| 235 | + m = 1.32171; |
| 236 | + pdg = 3312; |
| 237 | + cout<<"Adding extra xi: "<<lXiYield<<" (to reach average "<<Form("%.6f",lExpectedXi)<<" at this Nch = "<<nChargedParticlesAtMidRap<<", ratio: "<<Form("%.6f",lExpectedXiToPion)<<")"<<endl; |
| 238 | + for(Int_t ii=0; ii<lXiYield; ii++){ |
| 239 | + pdg *= gRandom->Uniform()>0.5?+1:-1; |
| 240 | + xProd=0.0; |
| 241 | + yProd=0.0; |
| 242 | + zProd=0.0; |
| 243 | + genSpectraMomentumEtaXi(genMinPt,genMaxPt,genminY,genmaxY); |
| 244 | + Pythia8::Particle lAddedParticle = createParticle(); |
| 245 | + mPythia.event.append(lAddedParticle); |
| 246 | + //lAddedParticles++; |
| 247 | + } |
| 248 | + //+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 249 | + |
| 250 | + //+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 251 | + // OMEGA ABUNDANCE FIX |
| 252 | + //Adjust relative abundance of multi-strange particles by injecting some |
| 253 | + Double_t lExpectedOmegaToPion = TMath::Max(8.55057e-04 - 7.38732e-04*TMath::Exp(-nChargedParticlesAtMidRap/2.40545e+01) - 6.56785e-05,0.); |
| 254 | + Double_t lExpectedOmega = 5.0*nPionsAtMidRap*lExpectedOmegaToPion; // extra rich, factor 5 |
| 255 | + Int_t lOmegaYield = gRandom->Poisson(3*lExpectedOmega); //factor 3: fix the rapidity acceptance |
| 256 | + m = 1.67245; |
| 257 | + pdg = 3334; |
| 258 | + cout<<"Adding extra omegas: "<<lOmegaYield<<" (to reach average "<<Form("%.6f",lExpectedOmega)<<" at this Nch = "<<nChargedParticlesAtMidRap<<", ratio: "<<Form("%.6f",lExpectedOmegaToPion)<<")"<<endl; |
| 259 | + for(Int_t ii=0; ii<lOmegaYield; ii++){ |
| 260 | + pdg *= gRandom->Uniform()>0.5?+1:-1; |
| 261 | + xProd=0.0; |
| 262 | + yProd=0.0; |
| 263 | + zProd=0.0; |
| 264 | + genSpectraMomentumEtaOm(genMinPt,genMaxPt,genminY,genmaxY); |
| 265 | + Pythia8::Particle lAddedParticle = createParticle(); |
| 266 | + mPythia.event.append(lAddedParticle); |
| 267 | + //lAddedParticles++; |
| 268 | + } |
| 269 | + //+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 270 | + |
| 271 | + //+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 272 | + // loop over the entire event record and rotate all particles |
| 273 | + // synthetic flow exercise |
| 274 | + // first: get event plane |
| 275 | + float eventPlaneAngle = mPythia.info.hiInfo->phi(); |
| 276 | + float impactParameter = mPythia.info.hiInfo->b(); |
| 277 | + |
| 278 | + for ( Long_t j=0; j < mPythia.event.size(); j++ ) { |
| 279 | + float pyphi = mPythia.event[j].phi(); |
| 280 | + float pypT = mPythia.event[j].pT(); |
| 281 | + |
| 282 | + // calculate delta with EP |
| 283 | + float deltaPhiEP = pyphi - eventPlaneAngle; |
| 284 | + float shift = 0.0; |
| 285 | + while(deltaPhiEP<0.0){ |
| 286 | + deltaPhiEP += 2*TMath::Pi(); |
| 287 | + shift += 2*TMath::Pi(); |
| 288 | + } |
| 289 | + while(deltaPhiEP>2*TMath::Pi()){ |
| 290 | + deltaPhiEP -= 2*TMath::Pi(); |
| 291 | + shift -= 2*TMath::Pi(); |
| 292 | + } |
| 293 | + float newDeltaPhiEP = lutGen->MapPhi(deltaPhiEP, impactParameter, pypT); |
| 294 | + float pyphiNew = newDeltaPhiEP - shift + eventPlaneAngle; |
| 295 | + |
| 296 | + if(pyphiNew>TMath::Pi()) |
| 297 | + pyphiNew -= 2.0*TMath::Pi(); |
| 298 | + if(pyphiNew<-TMath::Pi()) |
| 299 | + pyphiNew += 2.0*TMath::Pi(); |
| 300 | + mPythia.event[j].rot(0.0, pyphiNew-pyphi); |
| 301 | + } |
| 302 | + //+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 303 | + |
| 304 | + return true; |
| 305 | + } |
| 306 | + |
| 307 | +private: |
| 308 | + double genMinPt; /// minimum 3-momentum for generated particles |
| 309 | + double genMaxPt; /// maximum 3-momentum for generated particles |
| 310 | + double genminY; /// minimum pseudorapidity for generated particles |
| 311 | + double genmaxY; /// maximum pseudorapidity for generated particles |
| 312 | + double genminEta; |
| 313 | + double genmaxEta; |
| 314 | + |
| 315 | + Pythia8::Vec4 fourMomentum; /// four-momentum (px,py,pz,E) |
| 316 | + |
| 317 | + double E; /// energy: sqrt( m*m+px*px+py*py+pz*pz ) [GeV/c] |
| 318 | + double m; /// particle mass [GeV/c^2] |
| 319 | + int pdg; /// particle pdg code |
| 320 | + double px; /// x-component momentum [GeV/c] |
| 321 | + double py; /// y-component momentum [GeV/c] |
| 322 | + double pz; /// z-component momentum [GeV/c] |
| 323 | + double p; /// momentum |
| 324 | + double y; /// rapidity |
| 325 | + double eta; /// pseudorapidity |
| 326 | + double xProd; /// x-coordinate position production vertex [cm] |
| 327 | + double yProd; /// y-coordinate position production vertex [cm] |
| 328 | + double zProd; /// z-coordinate position production vertex [cm] |
| 329 | + |
| 330 | + std::unique_ptr<TLorentzVector> fLVHelper; |
| 331 | + std::unique_ptr<TF1> fSpectrumXi; |
| 332 | + std::unique_ptr<TF1> fSpectrumOm; |
| 333 | + o2::eventgen::FlowMapper *lutGen; // for mapping phi angles |
| 334 | +}; |
| 335 | + |
| 336 | + FairGenerator *generator_syntheFlowXi() |
| 337 | + { |
| 338 | + return new GeneratorPythia8SyntheFlowXi(); |
| 339 | + } |
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