Diffractive dijet production in (p)over-barp collisions at root s=1.96 TeV

We report on a study of diffractive dijet production in (p) over barp collisions at root s = 1.96 TeV using the CDF II detector at the Fermilab Tevatron (p) over barp collider. A data sample from 310 pb(-1) of integrated luminosity collected by triggering on a high transverse energy jet, E-T(jet), in coincidence with a recoil antiproton detected in a Roman pot spectrometer is used to measure the ratio of single-diffractive to inclusive-dijet event rates as a function of x((p) over bar) of the interacting parton in the antiproton, the Bjorken-x, x(Bj)((p) over bar), and a Q(2) approximate to (E-T(jet))(2) in the ranges 10(-3) < x(Bj)((p) over bar) < 10(-1) and 10(2) < Q(2) < 10(4) GeV2, respectively. Results are presented for the region of (p) over bar -momentum-loss fraction 0.03 < xi((p) over bar) < 0.09 and a four-momentum transfer squared t((p) over bar) > -4 GeV2. The t((p) over bar) dependence is measured as a function of Q(2) and x(Bj)((p) over bar) and compared with that of inclusive single diffraction dissociation. We find weak x(Bj)((p) over bar) and Q(2) dependencies in the ratio of single diffractive to inclusive event rates, and no significant Q(2) dependence in the diffractive t((p) over bar) distributions.