Diffractive Dijet Production at sqrt(s)=630 and 1800 GeV at the Fermilab Tevatron

Abstract

We report a measurement of the diffractive structure function $F_{jj}^D$ of the antiproton obtained from a study of dijet events produced in association with a leading antiproton in $\bar{p}p$ collisions at $\sqrt{s}=630$ GeV at the Fermilab Tevatron. The ratio of $F_{jj}^D$ at $\sqrt{s}=630$ GeV to $F_{jj}^D$ obtained from a similar measurement at $\sqrt{s}=1800$ GeV is compared with expectations from QCD factorization and with theoretical predictions. We also report a measurement of the $\xi$ ($x$-Pomeron) and $\beta$ ($x$ of parton in Pomeron) dependence of $F_{jj}^D$ at $\sqrt{s}=1800$ GeV. In the region $0.035<\xi <0.095$, $|t|<1$ GeV${}^2$ and $\beta <0.5$, $F_{jj}^D(\beta ,\xi )$ is found to be of the form ${\beta }^{-1.0\pm 0.1}{\xi }^{-0.9\pm 0.1}$, which obeys $\beta$-$\xi$ factorization.

LaTeX, 9 pages, Submitted to Phys. Rev. Letters