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Extracting the Proton ubar content from pp->Direct Photon plus Jet Cross Sections

R. G. Badalian·S. Heppelmann
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Abstract

An analysis procedure is proposed to measure the antiquark distributions in the proton over the region 0.01 < x < 0.1. The procedure involves the measurement of high p_t asymmetric direct photon and jet final states in pp interactions. This measurement can be made at the RHIC collider running in pp mode at an energy of sqrt(s)=500 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 ubar parton density function can be extracted.

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R. G. Badalian, S. Heppelmann. 1997-04-07. Extracting the Proton ubar content from pp->Direct Photon plus Jet Cross Sections. https://doi.org/10.1103/physrevd.57.4367

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