- Conference date: 19-24 May 2003
- Location: New York, NY (USA)
The Fermilab E866/NuSea Collaboration has measured the Drell‐Yan dimuon cross sections in 800 GeV/c proton‐proton and proton‐deuterium collisions. This is the first measurement of the absolute Drell‐Yan cross section in proton‐proton collisions over a broad kinematic region and the most extensive study to date of the Drell‐Yan cross section in proton‐deuterium collisions. The Drell‐Yan mechanism is sensitive to both the beam and target parton distributions. In particular, with the kinematics of the E866/NuSea data, the Drell‐Yan mechanism is sensitive to the target antiquark distributions at low and intermediate Bjorken‐x and to the beam quark distributions at high‐x. Approximately 55K proton‐proton and 121K proton‐deuterium Drell‐Yan events over the longitudinal momentum fraction (Feynman‐x) range −0.05 < xF < 0.8 and the mass ranges 4.2 < M μ+μ− < 8.7 GeV and 10.85 < M < 16.85 GeV are included. The data analysis will be described, and the doubly‐differential M 3 d 2σ/dMdxF , and triply‐differential cross sections Ed 3σ/dp 3 will be presented. These results will be compared with previous measurements by E605 and E772 and to predictions based upon next‐to‐leading order calculations utilizing the MRST2001 and CTEQ6 global parton distribution function fits. The results indicate that recent global parton distribution fits provide a good description of the light antiquark sea in the nucleon over the Bjorken‐x range 0.03 < x < 0.15. In contrast, the valence quark distributions appear to be overestimated by the current parton distribution fits as x → 1; a region in which, prior to this data, there was very little proton data to constrain the global fits.
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