On the thermalisation of leptons from heavy-flavour meson decay in pp collisions

It is shown that the ${\mu }^{\pm }$ originating from the decay of heavy-flavour mesons in the simulated proton-proton collisions at $\sqrt{s}=13$ TeV using the PYTHIA 8 event generator can be made into two groups based on the value of their light front variable such that one among these two groups of ${\mu }^{\pm }$ follow the Boltzmann statistics with a nearly isotropic angular distribution. A similar effect is not observed for $e^{\pm }$ from the decay of heavy-flavour mesons in these collisions.