Inclusive two jet triply differential cross section.

We study the inclusive two jet triply differential cross section {ital d}{sup 3}{sigma}/{ital dE}{sub {ital T}}{ital d}{eta}{sub 1}{ital d}{eta}{sub 2} at Fermilab energies. Different {eta}{sub 1} and {eta}{sub 2} pseudorapidity regions are directly related to both the parton level matrix elements and the parton densities at leading order. We present the next-to-leading order [{ital O}({alpha}{sub {ital s}}{sup 3})] corrections and show that the shape of the distribution at fixed transverse energy {ital E}{sub {ital T}} is a particularly powerful tool for constraining the parton distributions at small to moderate {ital x} values. We investigate the renormalization and/or factorization scale uncertainty present in the normalization and shape of the distribution at next-to-leading order. We discuss specific slices of the distribution, the same-side/opposite-side ratio, and the signed pseudorapidity distribution in detail and compare them with preliminary experimental data.