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arXiv · 0901.2169

Direct Measurement of the $W$ Production Charge Asymmetry in $\ppbar$ Collisions at $\sqrt{s} = 1.96$ TeV

The CDF Collaboration·T. Aaltonen
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Abstract

We present the first direct measurement of the $W$ production charge asymmetry as a function of the $W$ boson rapidity $\yW$ in $\ppbar$ collisions at $\sqrt{s} = 1.96$ $\TeV$. We use a sample of $\wenu$ events in data from 1 $\ifb$ of integrated luminosity collected using the CDF II detector. In the region $|\yW| <$ 3.0, this measurement is capable of constraining the ratio of up and down quark momentum distributions in the proton more directly than in previous measurements of the asymmetry that are a function of the charged-lepton pseudorapidity.

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The CDF Collaboration, T. Aaltonen. 2009-04-15. Direct Measurement of the $W$ Production Charge Asymmetry in $\ppbar$ Collisions at $\sqrt{s} = 1.96$ TeV. https://doi.org/10.1103/physrevlett.102.181801

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