Fragmentation production of J ψ and ψ′ at the Tevatron

Abstract

We present a calculation of the charm and gluon fragmentation contributions to inclusive J ψ and ψ′ production at large transverse momentum at the Tevatron. For ψ production, we include both fragmentation directly into ψ and fragmentation into χc followed by the radiative decay χc → ψ + λ. We find that fragmentation overwhelms the leading-order mechanisms for prompt ψ production at large pT, and that the dominant contributions come from fragmentation into χc. Our results are consistent with recent data on ψ production from the CDF and D0 experiments. In the case of prompt ψ′ production, the dominant mechanism at large pT is charm fragmentation into ψ′. We find serious disagreement between our theoretical predictions and recent ψ′ data from the Tevatron. © 1994.