PWGEM/PhotonMeson: apply min pt cut to trackiu (#6684)

Author: dsekihat

PWGEM/PhotonMeson/TableProducer/photonconversionbuilder.cxx

@@ -85,9 +85,10 @@ struct PhotonConversionBuilder {
   Configurable<float> maxTPCNsigmaEl{"maxTPCNsigmaEl", 4.0, "max. TPC n sigma for electron"};
   Configurable<float> dcanegtopv{"dcanegtopv", 0.1, "DCA Neg To PV"};
   Configurable<float> dcapostopv{"dcapostopv", 0.1, "DCA Pos To PV"};
-  Configurable<float> min_pt_leg{"min_pt_leg", 0.04, "min pT for v0 legs at SV"};
+  Configurable<float> min_pt_leg_at_sv{"min_pt_leg_at_sv", 0.0, "min pT for v0 legs at SV"};                                                    // this is obsolete.
   Configurable<float> max_mean_its_cluster_size{"max_mean_its_cluster_size", 16.f, "max. <ITS cluster size> x cos(lambda) for ITSonly tracks"}; // this is to suppress random combination for V0s with ITSonly tracks. default 3 + 1 for skimming.
   Configurable<float> maxX{"maxX", 83.1, "max X for track IU"};
+  Configurable<float> min_pt_trackiu{"min_pt_trackiu", 0.05, "min pT for trackiu"}; // this comes from online processing. pT of track seed is above 50 MeV/c in B = 0.5 T, 20 MeV/c in B = 0.2 T.
 
   // v0 cuts
   Configurable<float> min_v0cospa_tpconly{"min_v0cospa_tpconly", 0.99, "min V0 CosPA to V0s with TPConly tracks"}; // double -> N.B. dcos(x)/dx = 0 at x=0)
@@ -103,7 +104,7 @@ struct PhotonConversionBuilder {
   Configurable<float> margin_z{"margin_z", 7.0, "margin for z cut in cm"};
   Configurable<float> max_alpha_ap{"max_alpha_ap", 0.95, "max alpha for AP cut"};
   Configurable<float> max_qt_ap{"max_qt_ap", 0.01, "max qT for AP cut"};
-  Configurable<float> min_pt_v0{"min_pt_v0", 0.05, "min pT for v0 photons at PV"};
+  Configurable<float> min_pt_v0{"min_pt_v0", 0.1, "min pT for v0 photons at PV"};
   Configurable<float> max_pt_v0_itsonly{"max_pt_v0_itsonly", 0.3, "max pT for v0 photons wth 2 ITSonly tracks at PV"};
   Configurable<float> max_eta_v0{"max_eta_v0", 0.9, "max eta for v0 photons at PV"};
   Configurable<float> kfMassConstrain{"kfMassConstrain", -1.f, "mass constrain for the KFParticle mother particle"};
@@ -357,6 +358,10 @@ struct PhotonConversionBuilder {
       return;
     }
 
+    if (pos.pt() < min_pt_trackiu || ele.pt() < min_pt_trackiu) {
+      return;
+    }
+
     if (pos.globalIndex() == ele.globalIndex()) {
       return;
     }
@@ -537,7 +542,7 @@ struct PhotonConversionBuilder {
 
     float pos_pt = RecoDecay::sqrtSumOfSquares(kfp_pos_DecayVtx.GetPx(), kfp_pos_DecayVtx.GetPy());
     float ele_pt = RecoDecay::sqrtSumOfSquares(kfp_ele_DecayVtx.GetPx(), kfp_ele_DecayVtx.GetPy());
-    if (pos_pt < min_pt_leg || ele_pt < min_pt_leg) {
+    if (pos_pt < min_pt_leg_at_sv || ele_pt < min_pt_leg_at_sv) {
       return;
     }