Jet-fragmentation properties in p¯p collisions at √s =1.8 TeV

The charged-particle fractional momentum distribution within jets, D(z), has been measured in dijet events from 1.8-TeV p¯p collisions in the Collider Detector at Fermilab. As expected from scale breaking in quantum chromodynamics, the fragmentation function D(z) falls more steeply as dijet invariant mass increases from 60 to 200 GeV/${\mathit{c}}^2$. The average fraction of the jet momentum carried by charged particles is 0.65±0.02(stat)±0.08(syst).