DIFFRACTIVE J PSI PRODUCTION AS A PROBE OF THE GLUON COMPONENT IN THEPOMERON/

We present a study of large p(T) J/psi production in hard diffractive processes by Pomeron exchange at the Fermilab Tevatron. We find that t his process (<p(p)over bar>-->p + J/psi + X) can be used to probe the gluon content of the Pomeron and to measure the gluon fraction of the Pomeron. Direct diffractive J/psi production can also provide another crucial test for the color-octet fragmentation mechanism. Using the re normalized Pomeron Bur factor D approximate to 1/9, the single diffrac tive J/psi production cross section at large p(T)(greater than or equa l to 8 GeV) is found to be of the order of 0.01 nb, and the ratio of s ingle diffractive to nondiffractive J/psi production is 0.65+/-0.15% f or the gluon fraction f(g) = 0.7 +/- 0.2.