Charged-particle multiplicity distribution of heavy flavor decay leptons in proton–proton collisions using Pythia8 at LHC energies.

In this report, the production of heavy-flavor (HF) hadron decay leptons as a function of self-normalized charged-particle multiplicity ( N ch / 〈 N ch 〉) for proton–proton (p-p) collisions at s = 13 TeV has been discussed. The production of heavy-flavor (charm and bottom quarks) decay electrons (HFE) and muons (HFM) are measured at mid- (| y | < 1) and forward- (2.5 < y < 4) rapidity regions, respectively. The charged-particle multiplicity ( N ch ) is estimated at | η | < 1. The recent studies of ALICE experiment on charm production as a function of multiplicity in p-p collisions at s = 7 TeV and also inclusive and multiplicity-dependent production from heavy-flavor hadron decays in p-p and p-Pb collisions at s = 13 TeV and s N N = 8.16 TeV, respectively, are done. These studies motivate to calculate multiplicity dependence of HF meson decay leptons i.e., for electron and muon channels both. The multiplicity dependence HFE and HFM production are calculated using PYTHIA8 event generator. The multiple-parton interactions (MPI)-based color reconnection (CR) mechanism is added to the standalone PYTHIA8, to observe the signature of collectivity. To observe the impact of MPI effect, the simulation results (w/ and w/o CR mechanism) for pT-differential production cross-section of HFE in p-p collisions at s = 13 TeV at mid-rapidity in a pT range (0.5 < p T < 16 GeV/c) compared with ALICE data. At LHC, a linear increase of relative J / ψ as a function of charged-particle multiplicity is observed in p-p collisions. We have added the results of average pT (〈 p T 〉 and 〈 p T 2 〉) contributions as a function of multiplicity for both HFE and HFM productions. The same increasing trend is observed for relative HFE and HFM versus multiplicity. However, the results of mean pT (〈 p T 〉 and 〈 p T 2 〉) for HFE show much sharper increase with respect to HFM production. The results of nuclear modification factors like observables ( R c p and R p p ) versus pT could make us understand about the formation of quantum chromodynamics (QCD) medium in high multiplicity p-p collisions. [ABSTRACT FROM AUTHOR]