Add hypertriton gun on top of Pythia8 HI

Author: mpuccio

MC/config/PWGLF/ini/GeneratorLFHypertritonPbPb.ini

@@ -0,0 +1,9 @@
+[GeneratorExternal]
+fileName=${O2DPG_ROOT}/MC/config/PWGLF/pythia8/generator_pythia8_longlived.C
+funcName=generateLongLived(1010010030, 10)
+
+[GeneratorPythia8]
+config=${O2_ROOT}/share/Generators/egconfig/pythia8_hi.cfg
+
+[DecayerPythia8]
+config[0]=${O2_ROOT}/share/Generators/pythia8/decays/hypertriton.cfg

MC/config/PWGLF/pythia8/generator_pythia8_longlived.C

@@ -0,0 +1,83 @@
+#include "Pythia8/Pythia.h"
+#include "FairGenerator.h"
+#include "FairPrimaryGenerator.h"
+#include "Generators/GeneratorPythia8.h"
+#include "TRandom3.h"
+#include "TParticlePDG.h"
+#include "TDatabasePDG.h"
+#include "TMath.h"
+#include <cmath>
+
+using namespace Pythia8;
+
+class GeneratorPythia8LongLivedGun : public o2::eventgen::GeneratorPythia8
+{
+public:
+  /// constructor
+  GeneratorPythia8LongLivedGun(int input_pdg, int nInject = 1) : pdg{input_pdg}, nParticles{nInject}, m{getMass(input_pdg)}
+  {
+  }
+
+  ///  Destructor
+  ~GeneratorPythia8LongLivedGun() = default;
+
+  /// randomize the PDG code sign of core particle
+  void setRandomizePDGsign(bool val) { randomizePDGsign = val; }
+
+  /// get mass from TParticlePDG
+  double getMass(int input_pdg)
+  {
+    double mass = 0;
+    if (TDatabasePDG::Instance())
+    {
+      TParticlePDG *particle = TDatabasePDG::Instance()->GetParticle(input_pdg);
+      if (particle)
+      {
+        mass = particle->Mass();
+      }
+      else
+      {
+        std::cout << "===> Unknown particle requested, mass set to 0" << std::endl;
+      }
+    }
+    return mass;
+  }
+
+  //__________________________________________________________________
+  Bool_t importParticles() override
+  {
+    GeneratorPythia8::importParticles();
+    static int sign{1};
+    for (int i{0}; i < nParticles; ++i)
+    {
+      const double pt = gRandom->Uniform(genMinPt, genMaxPt);
+      const double eta = gRandom->Uniform(genMinEta, genMaxEta);
+      const double phi = gRandom->Uniform(0, TMath::TwoPi());
+      const double px{pt * std::cos(phi)};
+      const double py{pt * std::sin(phi)};
+      const double pz{pt * std::sinh(eta)};
+      const double et{std::hypot(std::hypot(pt, pz), m)};
+      sign *= randomizePDGsign ? -1 : 1;
+      mParticles.push_back(TParticle(sign * pdg, 1, -1, -1, -1, -1, px, py, pz, et, 0., 0., 0., 0.));
+    }
+    return true;
+  }
+
+private:
+  double genMinPt = 0.5;  /// minimum 3-momentum for generated particles
+  double genMaxPt = 12.;  /// maximum 3-momentum for generated particles
+  double genMinEta = -1.; /// minimum pseudorapidity for generated particles
+  double genMaxEta = -1.; /// maximum pseudorapidity for generated particles
+
+  double m = 0;       /// particle mass [GeV/c^2]
+  int pdg = 0;        /// particle pdg code
+  int nParticles = 1; /// Number of injected particles
+
+  bool randomizePDGsign = true; /// bool to randomize the PDG code of the core particle
+};
+
+///___________________________________________________________
+FairGenerator *generateLongLived(int pdg, int nInject)
+{
+  return new GeneratorPythia8LongLivedGun(pdg, nInject);
+}

MC/run/PWGLF/run_PbPb_HypertritonInjected.sh

@@ -0,0 +1,31 @@
+#!/bin/bash
+
+#
+# A example workflow MC->RECO->AOD for a simple pp min bias
+# production, targetting test beam conditions.
+
+# make sure O2DPG + O2 is loaded
+[ ! "${O2DPG_ROOT}" ] && echo "Error: This needs O2DPG loaded" && exit 1
+[ ! "${O2_ROOT}" ] && echo "Error: This needs O2 loaded" && exit 1
+
+# ----------- LOAD UTILITY FUNCTIONS --------------------------
+. ${O2_ROOT}/share/scripts/jobutils.sh
+
+# ----------- START ACTUAL JOB  -----------------------------
+
+NWORKERS=${NWORKERS:-8}
+MODULES="--skipModules ZDC"
+SIMENGINE=${SIMENGINE:-TGeant3}
+NSIGEVENTS=${NSIGEVENTS:-1}
+NBKGEVENTS=${NBKGEVENTS:-1}
+NTIMEFRAMES=${NTIMEFRAMES:-1}
+INTRATE=${INTRATE:-50000}
+[[ ${SPLITID} != "" ]] && SEED="-seed ${SPLITID}" || SEED=""
+
+# create workflow
+${O2DPG_ROOT}/MC/bin/o2dpg_sim_workflow.py -eCM 5500 -col PbPb -gen external -j ${NWORKERS} -ns ${NSIGEVENTS} -tf ${NTIMEFRAMES} -interactionRate ${INTRATE} -confKey "Diamond.width[2]=6." -e ${SIMENGINE} ${SEED} -mod "--skipModules ZDC" \
+        -ini ${O2DPG_ROOT}/MC/config/PWGLF/ini/GeneratorLFHypertritonPbPb.ini
+
+# run workflow
+# allow increased timeframe parallelism with --cpu-limit 32
+${O2DPG_ROOT}/MC/bin/o2_dpg_workflow_runner.py -f workflow.json -tt aod --cpu-limit 32