[SigmaProton generator] Add minPt for protons and sigmas separately (#2417)

Co-authored-by: Francesco Mazzaschi <fmazzasc@alipap1.cern.ch>

Author: fmazzasc

MC/config/PWGLF/ini/GeneratorSigmaProtonTriggered.ini

@@ -1,5 +1,5 @@
 [GeneratorExternal]
 fileName=${O2DPG_MC_CONFIG_ROOT}/MC/config/PWGLF/pythia8/generator_pythia8_sigma_hadron.C
-funcName=generateSigmaHadron(2212, 2, 1, 10, 0.8)
+funcName=generateSigmaHadron(2212, 2, 1, 0.5, 10, 0.5)
 [GeneratorPythia8] 
 config=${O2_ROOT}/share/Generators/egconfig/pythia8_inel.cfg

MC/config/PWGLF/pythia8/generator_pythia8_sigma_hadron.C

@@ -26,19 +26,20 @@ class GeneratorPythia8SigmaHadron : public o2::eventgen::GeneratorPythia8
 {
 public:
   /// Constructor
-  GeneratorPythia8SigmaHadron(int hadronPdg, int gapSize = 4, double minPt = 0.2,
+  GeneratorPythia8SigmaHadron(int hadronPdg, int gapSize = 4, double minSigmaPt = 0.2, double minHadronPt = 0.2,
                               double maxPt = 10, double maxEta = 0.8, double kStarMax = 1.0)
       : o2::eventgen::GeneratorPythia8(),
         mHadronPdg(hadronPdg),
         mGapSize(gapSize),
-        mMinPt(minPt),
+        mMinSigmaPt(minSigmaPt),
+        mMinHadronPt(minHadronPt),
         mMaxPt(maxPt),
         mMaxEta(maxEta),
         mKStarMax(kStarMax)
   {
     fmt::printf(
-        ">> Pythia8 generator: Sigma± + hadron(PDG=%d), gap = %d, minPt = %f, maxPt = %f, |eta| < %f, k* < %f\n",
-        hadronPdg, gapSize, minPt, maxPt, maxEta, kStarMax);
+        ">> Pythia8 generator: Sigma± + hadron(PDG=%d), gap = %d, minSigmaPt = %f, minHadronPt = %f, maxPt = %f, |eta| < %f, k* < %f\n",
+        hadronPdg, gapSize, minSigmaPt, minHadronPt, maxPt, maxEta, kStarMax);
   }
 
   ~GeneratorPythia8SigmaHadron() = default;
@@ -135,19 +136,19 @@ protected:
     for (int i = 0; i < event.size(); i++) {
       const auto& p = event[i];
 
-      if (std::abs(p.eta()) > mMaxEta || p.pT() < mMinPt || p.pT() > mMaxPt) {
+      if (std::abs(p.eta()) > mMaxEta || p.pT() > mMaxPt) {
         continue;
       }
 
       const int pdg = p.id();
       const int absPdg = std::abs(pdg);
 
       // Sigma- or Sigma+
-      if (absPdg == 3112 || absPdg == 3222) {
+      if ((absPdg == 3112 || absPdg == 3222) && p.pT() >= mMinSigmaPt) {
         sigmaIndices.push_back(i);
       }
 
-      if (std::abs(pdg) == mHadronPdg && !isFromSigmaDecay(p, event)) {
+      if (std::abs(pdg) == mHadronPdg && p.pT() >= mMinHadronPt && !isFromSigmaDecay(p, event)) {
         hadronIndices.push_back(i);
       }
     }
@@ -178,18 +179,19 @@ protected:
 private:
   int mHadronPdg{211};
   int mGapSize{4};
-  double mMinPt{0.2};
+  double mMinSigmaPt{0.2};
+  double mMinHadronPt{0.2};
   double mMaxPt{10.0};
   double mMaxEta{0.8};
   double mKStarMax{1.0};
   uint64_t mGeneratedEvents{0};
 };
 
 ///___________________________________________________________
-FairGenerator* generateSigmaHadron(int hadronPdg, int gap = 4, double minPt = 0.2,
+FairGenerator* generateSigmaHadron(int hadronPdg, int gap = 4, double minSigmaPt = 0.2, double minHadronPt = 0.2,
                                    double maxPt = 10, double maxEta = 0.8, double kStarMax = 1.0)
 {
-  auto myGenerator = new GeneratorPythia8SigmaHadron(hadronPdg, gap, minPt, maxPt, maxEta, kStarMax);
+  auto myGenerator = new GeneratorPythia8SigmaHadron(hadronPdg, gap, minSigmaPt, minHadronPt, maxPt, maxEta, kStarMax);
   auto seed = (gRandom->TRandom::GetSeed() % 900000000);
   myGenerator->readString("Random:setSeed on");
   myGenerator->readString("Random:seed " + std::to_string(seed));