diff --git a/PWGCF/GenericFramework/Tasks/flowGenericFramework.cxx b/PWGCF/GenericFramework/Tasks/flowGenericFramework.cxx
index 9f419324209..4378565008e 100644
--- a/PWGCF/GenericFramework/Tasks/flowGenericFramework.cxx
+++ b/PWGCF/GenericFramework/Tasks/flowGenericFramework.cxx
@@ -115,7 +115,7 @@ struct FlowGenericFramework {
   Configurable<std::vector<double>> cfgTrackDensityP0{"cfgTrackDensityP0", std::vector<double>{0.7217476707, 0.7384792571, 0.7542625668, 0.7640680200, 0.7701951667, 0.7755299053, 0.7805901710, 0.7849446786, 0.7957356586, 0.8113039262, 0.8211968966, 0.8280558878, 0.8329342135}, "parameter 0 for track density efficiency correction"};
   Configurable<std::vector<double>> cfgTrackDensityP1{"cfgTrackDensityP1", std::vector<double>{-2.169488e-05, -2.191913e-05, -2.295484e-05, -2.556538e-05, -2.754463e-05, -2.816832e-05, -2.846502e-05, -2.843857e-05, -2.705974e-05, -2.477018e-05, -2.321730e-05, -2.203315e-05, -2.109474e-05}, "parameter 1 for track density efficiency correction"};
 
-  Configurable<GFWBinningCuts> cfgGFWBinning{"cfgGFWBinning", {40, 16, 72, 300, 0, 3000, 0.2, 10.0, 0.2, 3.0, {0.2, 0.25, 0.3, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, 0.65, 0.7, 0.75, 0.8, 0.85, 0.9, 0.95, 1, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2, 2.2, 2.4, 2.6, 2.8, 3, 3.5, 4, 5, 6, 8, 10}, {0, 5, 10, 20, 30, 40, 50, 60, 70, 80, 90}}, "Configuration for binning"};
+  Configurable<GFWBinningCuts> cfgGFWBinning{"cfgGFWBinning", {40, 16, 72, 300, 0, 3000, 0.2, 10.0, 0.2, 3.0, {0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1, 1.25, 1.5, 1.75, 2, 2.25, 2.5, 2.75, 3, 3.25, 3.5, 3.75, 4, 4.5, 5, 5.5, 6, 7, 8, 9, 10}, {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90}}, "Configuration for binning"};
   Configurable<GFWRegions> cfgRegions{"cfgRegions", {{"refN", "refP", "refFull"}, {-0.8, 0.4, -0.8}, {-0.4, 0.8, 0.8}, {0, 0, 0}, {1, 1, 1}}, "Configurations for GFW regions"};
 
   Configurable<GFWCorrConfigs> cfgCorrConfig{"cfgCorrConfig", {{"refP {2} refN {-2}", "refP {3} refN {-3}", "refP {4} refN {-4}", "refFull {2 -2}", "refFull {2 2 -2 -2}"}, {"ChGap22", "ChGap32", "ChGap42", "ChFull22", "ChFull24"}, {0, 0, 0, 0, 0}, {15, 1, 1, 0, 0}}, "Configurations for each correlation to calculate"};
@@ -261,6 +261,7 @@ struct FlowGenericFramework {
       nchbinning.push_back(nchskip * i + o2::analysis::gfw::nchlow + 0.5);
     }
     AxisSpec nchAxis = {nchbinning, "N_{ch}"};
+    AxisSpec bAxis = {200, 0, 20, "#it{b}"};
     AxisSpec t0cAxis = {70, 0, 70000, "N_{ch} (T0C)"};
     AxisSpec t0aAxis = {200, 0, 200, "N_{ch}"};
     AxisSpec multpvAxis = {4000, 0, 4000, "N_{ch} (PV)"};
@@ -277,10 +278,11 @@ struct FlowGenericFramework {
     int ptbins = o2::analysis::gfw::ptbinning.size() - 1;
     fPtAxis = new TAxis(ptbins, &o2::analysis::gfw::ptbinning[0]);
 
-    if (doprocessMCGen) {
+    if (doprocessMCGen || doprocessOnTheFly) {
       registry.add("MCGen/before/pt_gen", "", {HistType::kTH1D, {ptAxis}});
       registry.add("MCGen/before/phi_eta_vtxZ_gen", "", {HistType::kTH3D, {phiAxis, etaAxis, vtxAxis}});
       registry.addClone("MCGen/before/", "MCGen/after/");
+      registry.add("MCGen/impactParameter", "", {HistType::kTH2D, {{bAxis, nchAxis}}});
     }
     if (doprocessMCReco || doprocessData || doprocessRun2) {
       registry.add("trackQA/before/phi_eta_vtxZ", "", {HistType::kTH3D, {phiAxis, etaAxis, vtxAxis}});
@@ -349,7 +351,7 @@ struct FlowGenericFramework {
       fFC->SetXAxis(fPtAxis);
       fFC->Initialize(oba, multAxis, cfgNbootstrap);
     }
-    if (doprocessMCGen) {
+    if (doprocessMCGen || doprocessOnTheFly) {
       fFCgen->SetName("FlowContainer_gen");
       fFCgen->SetXAxis(fPtAxis);
       fFCgen->Initialize(oba, multAxis, cfgNbootstrap);
@@ -988,6 +990,7 @@ struct FlowGenericFramework {
 
   o2::framework::expressions::Filter collisionFilter = nabs(aod::collision::posZ) < cfgVtxZ;
   o2::framework::expressions::Filter trackFilter = nabs(aod::track::eta) < cfgEta && aod::track::pt > cfgPtmin&& aod::track::pt < cfgPtmax && ((requireGlobalTrackInFilter()) || (aod::track::isGlobalTrackSDD == (uint8_t) true)) && nabs(aod::track::dcaXY) < cfgDCAxy&& nabs(aod::track::dcaZ) < cfgDCAz;
+
   using GFWTracks = soa::Filtered<soa::Join<aod::Tracks, aod::TracksExtra, aod::TrackSelection, aod::TracksDCA, aod::pidTOFPi, aod::pidTPCPi, aod::pidTOFKa, aod::pidTPCKa, aod::pidTOFPr, aod::pidTPCPr>>;
 
   void processData(soa::Filtered<soa::Join<aod::Collisions, aod::EvSels, aod::Mults, aod::CentFT0Cs, aod::CentFT0CVariant1s, aod::CentFT0Ms, aod::CentFV0As>>::iterator const& collision, aod::BCsWithTimestamps const&, GFWTracks const& tracks)
@@ -1101,6 +1104,7 @@ struct FlowGenericFramework {
   {
     float centrality = -1;
     int run = 0;
+    registry.fill(HIST("MCGen/impactParamter"), mcCollision.impactParameter(), mcParticles.size());
     processCollision<kGen>(mcCollision, mcParticles, centrality, run);
   }
   PROCESS_SWITCH(FlowGenericFramework, processOnTheFly, "Process analysis for MC on-the-fly generated events", false);