[MC] Scripts needed to run upcgen as external generator (#1811)

* Adding scripts which are required to use the event generator upcgen in O2 simulations.

Author: pbuehler

MC/config/PWGUD/external/generator/GeneratorUpcgen.C

@@ -0,0 +1,175 @@
+R__LOAD_LIBRARY(libUpcgenlib.so)
+R__ADD_INCLUDE_PATH($upcgen_ROOT/include)
+
+#include "UpcGenerator.h"
+
+// usage: o2-sim -n 100 -g external --configKeyValues 'GeneratorExternal.fileName=GeneratorUpcgen.C;GeneratorExternal.funcName=GeneratorUpcgen("kDiTau")'
+
+namespace o2 {
+namespace eventgen {
+class GeneratorUPCgen_class : public Generator {
+public:
+  GeneratorUPCgen_class() { mUPCgen = new UpcGenerator(); };
+  ~GeneratorUPCgen_class() = default;
+  void selectConfiguration(std::string val) { mSelectedConfiguration = val; };
+  void setLumiFileDirectory(std::string lumiFileDirectory) {
+    mUPCgen->setLumiFileDirectory(lumiFileDirectory);
+  };
+  void setCollisionSystem(float energyCM, int beamZ, int beamA) {
+    eCM = energyCM;
+    projZ = beamZ;
+    projA = beamA;
+  };
+  void setSeed(int seed) { mUPCgen->setSeed(seed); }
+
+  // predefined generator configurations
+  const static int nProcess = 5;
+  const static int nElements = 9;
+  const struct UpcgenConfig {
+    std::string pnames[nElements]{"PROC_ID",   "LEP_A",      "ALP_MASS",
+                                  "ALP_WIDTH", "PT_MIN",     "ETA_MIN",
+                                  "ETA_MAX",   "FLUX_POINT", "BREAKUP_MODE"};
+    const struct definitions {
+      const char *name;
+      std::string elements[nElements];
+    } sets[nProcess] = {
+        {"kDiElectron",
+         {"11", "0.0", "0.0", "0.0", "0.0", "-1.0", "1.0", "1", "1"}},
+        {"kDiMuon",
+         {"13", "0.0", "0.0", "0.0", "0.0", "-1.0", "1.0", "1", "1"}},
+        {"kDiTau", {"15", "0.0", "0.0", "0.0", "0.0", "-1.0", "1.0", "1", "1"}},
+        {"kLightByLight",
+         {"22", "0.0", "0.0", "0.0", "0.0", "-1.0", "1.0", "1", "1"}},
+        {"kAxionLike",
+         {"51", "0.0", "0.0", "0.0", "0.0", "-1.0", "1.0", "1", "1"}}};
+  } upcgenConfig;
+
+  bool Config() {
+    // select a specific set of parameters
+    int idx = -1;
+    for (int i = 0; i < nProcess; ++i) {
+      if (mSelectedConfiguration.compare(upcgenConfig.sets[i].name) == 0) {
+        idx = i;
+        break;
+      }
+    }
+
+    if (idx == -1) {
+      std::cout << "UPCGEN process " << mSelectedConfiguration
+                << " is not supported" << std::endl;
+      return false;
+    }
+
+    // new generator
+    mUPCgen->setDebugLevel(0);
+    mUPCgen->setNumThreads(1);
+
+    // update generator parameters - configure
+    mUPCgen->setParameterValue("DO_PT_CUT", "1");
+    mUPCgen->setParameterValue("DO_ETA_CUT", "1");
+    mUPCgen->setParameterValue("USE_ROOT_OUTPUT", "0");
+    mUPCgen->setParameterValue("USE_HEPMC_OUTPUT", "0");
+
+    for (int i = 0; i < nElements; ++i) {
+      mUPCgen->setParameterValue(upcgenConfig.pnames[i],
+                                 upcgenConfig.sets[idx].elements[i]);
+    }
+
+    return true;
+  }
+
+  bool Init() override {
+    Generator::Init();
+
+    // initialize the generator
+    mUPCgen->init();
+
+    return true;
+  };
+
+  bool generateEvent() override {
+    if (!mUPCgen) {
+      std::cout << "GenerateEvent: upcgen class/object not properly constructed"
+                << std::endl;
+      return false;
+    }
+
+    // generate a new event
+    vector<int> pdgs;
+    vector<int> statuses;
+    vector<int> mothers;
+    vector<TLorentzVector> particles;
+    // events can be rejected due to applied cuts
+    bool goon = true;
+    while (goon) {
+      auto stat = mUPCgen->generateEvent(pdgs, statuses, mothers, particles);
+      if (stat == 0) {
+        nRejected++;
+      } else {
+        nAccepted++;
+        goon = false;
+      }
+    }
+
+    return true;
+  };
+
+  bool importParticles() override {
+    std::cout << "\n";
+    auto upcgenParticles = mUPCgen->getParticles();
+    for (auto part : upcgenParticles) {
+      part.Print();
+      TParticle particle(part.GetPdgCode(), 1, part.GetFirstMother(), -1,
+                         part.GetFirstDaughter(), part.GetLastDaughter(),
+                         part.Px(), part.Py(), part.Pz(), part.Energy(), 0., 0.,
+                         0., 0.);
+      mParticles.push_back(particle);
+      o2::mcutils::MCGenHelper::encodeParticleStatusAndTracking(
+          mParticles.back(), true);
+    }
+    return true;
+  };
+
+  long int acceptedEvents() { return nAccepted; }
+  long int rejectedEvents() { return nRejected; }
+  double fiducialXSection() {
+    return mUPCgen->totNuclX() * nAccepted / (nAccepted + nRejected);
+  }
+
+private:
+  UpcGenerator *mUPCgen = 0x0;
+  std::string mSelectedConfiguration = "";
+
+  // keep track of the rejected and accepted events
+  long int nAccepted{0};
+  long int nRejected{0};
+
+  float eCM = 5020;
+  int projZ = 82;
+  int projA = 208;
+};
+
+} // namespace eventgen
+} // namespace o2
+
+FairGenerator *GeneratorUpcgen(std::string configuration = "kDiTau",
+                               std::string lumiFileDirectory = ".",
+                               float energyCM = 5020., int beamZ = 82,
+                               int beamA = 208) {
+  // create generator
+  auto gen = new o2::eventgen::GeneratorUPCgen_class();
+
+  // set generator parameters
+  gen->selectConfiguration(configuration);
+  gen->setLumiFileDirectory(lumiFileDirectory);
+  gen->setCollisionSystem(energyCM, beamZ, beamA);
+
+  // configure the generator
+  cout << "Upcgen is initialized ...";
+  gen->Config();
+  cout << " config done ...";
+  gen->Init();
+  cout << " init done!\n";
+
+  return gen;
+}

MC/config/PWGUD/ini/makeUpcgenConfig.py

@@ -0,0 +1,59 @@
+#! /usr/bin/env python3
+
+### @author: Paul Buehler
+### @email: paul.buhler@cern.ch
+
+import argparse
+
+parser = argparse.ArgumentParser(description='Make Upcgen configuration',
+                                 formatter_class=argparse.ArgumentDefaultsHelpFormatter)
+
+parser.add_argument('--collType',default='PbPb', choices=['PbPb', 'OO'],
+                   help='Colission system')
+                   
+parser.add_argument('--eCM', type=float, default='5360',
+                    help='Centre-of-mass energy')
+
+parser.add_argument('--rapidity', default='cent', choices=['cent_eta', 'muon_eta'],
+                    help='Rapidity to select')
+
+parser.add_argument('--process',default=None, choices=['kDiElectron', 'kDiMuon', 'kDiTau', 'kLightByLight', 'kAxionLike'],
+                    help='Process to switch on')
+                    
+                    
+parser.add_argument('--output', default='GenUpcgen.ini',
+                    help='Where to write the configuration')
+
+
+args = parser.parse_args()
+
+if 'PbPb' in args.collType:
+    pZ = 82
+    pA = 208
+
+if 'OO' in args.collType:
+    pZ = 8
+    pA = 16
+
+### open output file
+fout = open(args.output, 'w')
+
+### Generator
+fout.write('[GeneratorExternal] \n')
+fout.write('fileName = ${O2DPG_ROOT}/MC/config/PWGUD/external/generator/GeneratorUpcgen.C \n')
+fout.write('funcName = GeneratorUpcgen("%s", "%s", %f, %d, %d)  \n' % (args.process,"../.",args.eCM,pZ,pA))
+    
+###Trigger
+fout.write('[TriggerExternal] \n')
+fout.write('fileName = ${O2DPG_ROOT}/MC/config/PWGUD/trigger/selectParticlesInAcceptance.C \n')
+if args.rapidity == 'cent_rap':
+    fout.write('funcName = selectMotherPartInAcc(-0.9,0.9) \n')
+if args.rapidity == 'muon_rap':
+    fout.write('funcName = selectMotherPartInAcc(-4.0,-2.5) \n')
+if args.rapidity == 'cent_eta':
+    fout.write('funcName = selectDaughterPartInAcc(-0.95,0.95) \n')
+if args.rapidity == 'muon_eta':
+    fout.write('funcName = selectDaughterPartInAcc(-4.05,-2.45) \n')
+
+### close outout file
+fout.close()

MC/run/PWGUD/runUpcgenANCHOR.sh

@@ -0,0 +1,30 @@
+# Run as:  ${O2DPG_ROOT}/GRID/utils/grid_submit.sh --script ./runUpcgenANCHOR.sh --jobname SLtest --outputspec "*.log@disk=1","*.root@disk=2" --packagespec "VO_ALICE@O2sim::v20240626-1" --wait --fetch-output --asuser pbuhler --local
+
+export ALIEN_JDL_LPMANCHORPASSNAME=apass2
+export ALIEN_JDL_MCANCHOR=apass2
+export ALIEN_JDL_COLLISIONSYSTEM=PbPb
+export ALIEN_JDL_CPULIMIT=8
+export ALIEN_JDL_LPMPASSNAME=apass2
+export ALIEN_JDL_LPMRUNNUMBER=544389
+export ALIEN_JDL_LPMPRODUCTIONTYPE=MC
+export ALIEN_JDL_LPMINTERACTIONTYPE=PbPb
+export ALIEN_JDL_LPMPRODUCTIONTAG=MyPass2Test
+export ALIEN_JDL_LPMANCHORRUN=544389
+export ALIEN_JDL_LPMANCHORPRODUCTION=LHC23zzi
+export ALIEN_JDL_LPMANCHORYEAR=2023
+
+export NTIMEFRAMES=2
+export NSIGEVENTS=5
+export NBKGEVENTS=1
+export SPLITID=2
+export PRODSPLIT=100
+export CYCLE=0
+export ALIEN_PROC_ID=2963436952
+
+
+#export ALIEN_JDL_ANCHOR_SIM_OPTIONS="-gen external -ini ${PWD}/GenUpcgen.ini --embedding -nb ${NBKGEVENTS} -colBkg PbPb -genBkg pythia8 -procBkg heavy_ion"
+
+${O2DPG_ROOT}/MC/config/PWGUD/ini/makeUpcgenConfig.py --process kDiTau --collType PbPb --eCM 5360 --rapidity cent_eta
+export ALIEN_JDL_ANCHOR_SIM_OPTIONS="-gen external -ini ${PWD}/GenUpcgen.ini"
+
+${O2DPG_ROOT}/MC/run/ANCHOR/anchorMC.sh