Double Diffractive Process Factorization from ηc and γ Associated Production at Tevatron and LHC**The project supported in part by National Natural Science Foundation of China under Grant No. 10175074, the Natural Science Foundation of Hebei Province of China under Grant No. 103143, and the Youth Foundation of North China Electric Power University under Grant No. 060214

Abstract

We present a study of associated and double diffractive production in collision based on Ingelman-Schlein model, and the framework of non-relativistic QCD factorization formalism for quarkonia production. The prediction of and is more reliable than production, because the associated and production is a pure color-octet process, and the dominant contribution comes from color octet subprocess, which is related to the color octet matrix element of of by the heavy quark spin symmetry and the large production data. We find that the ratio of diffractive to inclusive cross sections is independent of the values of color octet matrix elements, but is sensitive to the gluon factor of the Pomeron and renormalized Pomeron flux factors. So experimental measurement of this ratio can give us more information of the nature of Pomeron and test the assumption of hard diffractive factorization in hadron-hadron collisions.