Mean multiplicity of light and heavy quark initiated jets

TL;DR

This paper extends QCD jet evolution equations to include heavy quark masses, revealing that heavy-quark initiated jets have significantly lower multiplicities than massless jets, aiding collider particle identification.

Contribution

It introduces a mass-dependent modification to QCD evolution equations, extending the dead cone effect to jet multiplicity phenomenology.

Findings

Heavy-quark jets have lower charged hadron multiplicity than massless jets.

The study provides a new method to distinguish heavy-quark jets at colliders.

Results support improved b-tagging techniques at Tevatron and LHC.

Abstract

After inserting the heavy quark mass dependence into QCD partonic evolution equations, we determine the mean charged hadron multiplicity of jets produced in high energy collisions. We thereby extend the so-called dead cone effect to the phenomenology of multiparticle production in QCD jets and find that the average multiplicity of heavy-quark initiated jets decreases significantly as compared to the massless case, even taking into account the weak decay products of the leading primary quark. We emphasize the relevance of our study as a complementary check of $b$-tagging techniques at hadron colliders like the Tevatron and the LHC.