Charm-sea Contribution to High-p_T \psi Production at the Fermilab Tevatron

The direct production of $J\mathrm{/}\psi ({\psi }^{\mathrm{\prime }})$ at large transverse momentum, $p_T \gg M_{J/\psi}$, at the Fermilab Tevatron is revisited. It is found that the sea-quark initiated processes dominate in the high-$p_T$ region within the framework of color-singlet model, which is not widely realized. We think this finding is enlightening for further investigation on the charmonium production mechanism.