We study leptoproduction of at large within the nonrelativistic QCD (NRQCD) factorization formalism. The cross section is dominated by color-octet terms that are of order The color-singlet term, which is of order , is shown to make a small contribution to the total cross section. We also calculate the tree diagrams for color-octet production at order 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 is increased. Therefore, the color-octet matrix elements and can be reliably extracted from this process. Finally, we point out that an experimental measurement of the polarization of leptoproduced will provide an excellent test of the NRQCD factorization formalism.
- Received 17 July 1997
- Published in the issue dated 1 February 1998
© 1998 The American Physical Society