Heavy flavors in jets from perturbative QCD

We evaluate the charm and b-flavor content of high-$p_T$ jets in pp¯ collisions at √s =540 GeV, on the basis of perturbative QCD through order ${\alpha }_s$ ${\mathrm{}}^3$. The resulting charm fraction is of order 5% for jets with ‖η‖≤1 and 10<$p_T$<50 GeV, in agreement with estimates based on evolution equations for structure and fragmentation functions, indicating that the much larger value found in a recent experiment by the UA1 collaboration requires a nonperturbative origin.