Abstract
Elastic virtual photoproduction cross sections and total charmonium-nucleon cross sections for and states are calculated in a parameter-free way with the light-cone dipole formalism and the same input: factorization in impact parameters, light-cone wave functions for the and the charmonia, and the universal phenomenological dipole cross section which is fitted to other data. The charmonium wave functions are calculated with four known realistic potentials, and two models for the dipole cross section are tested. Very good agreement with data for the cross section of charmonium photoproduction is found in a wide range of s and The inclusion of the Melosh spin rotation increases the photoproduction rate by a factor of 2–3 and removes previously observed discrepancies in the to ratio in photoproduction. We also calculate the charmonium-proton cross sections whose absolute values and energy dependences are found to correlate strongly with the sizes of the states.
- Received 20 July 2000
DOI:https://doi.org/10.1103/PhysRevD.62.094022
©2000 American Physical Society