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arXiv · hep-ex/9807013

The Flavor Asymmetry of the Light Quark Sea from Semi-inclusive Deep-inelastic Scattering

K. Ackerstaff
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Abstract

The flavor asymmetry of the light quark sea of the nucleon is determined in the kinematic range 0.02<x<0.3 and 1 GeV^2<Q^2<10 GeV^2, for the first time from semi-inclusive deep-inelastic scattering. The quantity (dbar(x)-ubar(x))/(u(x)-d(x)) is derived from a relationship between the yields of positive and negative pions from unpolarized hydrogen and deuterium targets. The flavor asymmetry dbar-ubar is found to be non-zero and x dependent, showing an excess of dbar over ubar quarks in the proton.

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K. Ackerstaff. 1998-11-15. The Flavor Asymmetry of the Light Quark Sea from Semi-inclusive Deep-inelastic Scattering. https://doi.org/10.1103/physrevlett.81.5519

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