Analytic and Monte Carlo studies of jets with heavy mesons and quarkonia

We study jets with identified hadrons in which a family of jet-shape variables called angularities are measured, extending the concept of fragmenting jet functions (fjfs) to these observables. fjfs determine the fraction of energy, z, carried by an identified hadron in a jet with angularity, τ a . the fjfs are convolutions of fragmentation functions (ffs), evolved to the jet energy scale, with perturbatively calculable matching coefficients. renormalization group equations are used to provide resummed calculations with next-to-leading logarithm prime (nll’) accuracy. we apply this formalism to two-jet events in e + e − collisions with b mesons in the jets, and three-jet events in which a j/ψ is produced in the gluon jet. in the case of b mesons, we use a phenomenological ff extracted from e + e − collisions at the z 0 pole evaluated at the scale μ = m b . for events with j/ψ, the ff can be evaluated in terms of non-relativistic qcd (nrqcd) matrix elements at the scale μ = 2m c . the z and τ a distributions from our nll’ calculations are compared with predictions from monte carlo event generators. while we find consistency between the predictions for b mesons and the j/ψ distributions in τ a , we find the z distributions for j/ψ differ significantly. we describe an attempt to merge pythia showers with nrqcd ffs that gives good agreement with nll’ calculations of the z distributions.