Fragmentation production of J/psi and psi' at the Tevatron

Abstract

We present a calculation of the charm and gluon fragmentation contributions to inclusive $J/\psi$ and ${\psi }^{\prime }$ production at large transverse momentum at the Tevatron. For $\psi$ production, we include both fragmentation directly into $\psi$ and fragmentation into ${\chi }_c$ followed by the radiative decay ${\chi }_c\to \psi +\gamma$. We find that fragmentation overwhelms the leading-order mechanisms for prompt $\psi$ production at large $p_T$, and that the dominant contributions come from fragmentation into ${\chi }_c$. Our results are consistent with recent data on $\psi$ production from the CDF and D0 experiments. In the case of prompt ${\psi }^{\prime }$ production, the dominant mechanism at large $p_T$ is charm fragmentation into ${\psi }^{\prime }$. We find serious disagreement between our theoretical predictions and recent ${\psi }^{\prime }$ data from the Tevatron.

Comments: 13 pages with 4 figures appended to end as TOPDRAWER files