Leptoproduction of J/{psi}

We study leptoproduction of J/{psi} at large Q{sup 2} within the nonrelativistic QCD (NRQCD) factorization formalism. The cross section is dominated by color-octet terms that are of order {alpha}{sub s}. The color-singlet term, which is of order {alpha}{sub s}{sup 2}, is shown to make a small contribution to the total cross section. We also calculate the tree diagrams for color-octet production at order {alpha}{sub s}{sup 2} in a region of phase space where there is no leading color-octet contribution. We find that in this regime the color-singlet contribution dominates. We argue that nonperturbative corrections arising from diffractive leptoproduction, higher twist effects, and higher order terms in the NRQCD velocity expansion should be suppressed as Q{sup 2} is increased. Therefore, the color-octet matrix elements {l_angle}O{sub 8}{sup {psi}}({sup 1}S{sub 0}){r_angle} and {l_angle}O{sub 8}{sup {psi}}({sup 3}P{sub 0}){r_angle} can be reliably extracted from this process. Finally, we point out that an experimental measurement of the polarization of leptoproduced J/{psi} will provide an excellent test of the NRQCD factorization formalism. {copyright} {ital 1998} {ital The American Physical Society}