Gluon jets from quarkonia

Abstract

A detailed analysis is made within perturbative QCD of the decays into gluon jets of P-wave and S-wave quarkonia ( J PC = 0 ++, 1 ++, 2 ++, 1 +− and 0 −+, 1 −−). For all those states we compute to leading non-trivial order in α s the conventional fraction f( ϵ, δ) of the jet-like hadronic final states, characterized by the back-to-back cone of half angle δ, in which all but a small fraction ϵ of the total energy is emitted. To the same order we give also the average values of thrust momenta and spherocity distributions.