Extracting the proton $ū$ content from $p\overrightarrow{p}$ direct photon plus jet cross sections

An analysis procedure is proposed to measure the antiquark distributions in the proton over the region $0.01<x<\mathrm{}0.1\mathrm{}$. The procedure involves the measurement of high $p_t$ asymmetric direct photon and jet final states in $\mathrm{pp}$ interactions. This measurement can be made at the BNL RHIC collider running in $\mathrm{pp}$ mode at an energy of $\sqrt{s}=500\mathrm{}$ $\mathrm{GeV}/c$. This analysis identifies a region of phase space where the contribution from quark-antiquark annihilation uncharacteristically approaches the magnitude of the contribution from the leading process, quark-gluon Compton scattering. The forward-backward angular asymmetry in the parton center of mass is sensitive to the antiquark content of the proton and the $ū$ parton density function can be extracted.