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arXiv · 1103.2929

Measurement of the $W$ Charge Asymmetry in the $W \rightarrow \mu\nu$ Decay Mode in $pp$ Collisions at $\sqrt{s} = 7$ TeV with the ATLAS detector

The ATLAS Collaboration
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Abstract

This letter reports a measurement of the muon charge asymmetry from $W$ bosons produced in proton-proton collisions at a centre-of-mass energy of 7 TeV with the ATLAS experiment at the LHC. The asymmetry is measured in the $W \rightarrow \mu\nu$ decay mode as a function of the muon pseudorapidity using a data sample corresponding to a total integrated luminosity of 31 pb$^{-1}$. The results are compared to predictions based on next-to-leading order calculations with various parton distribution functions. This measurement provides information on the $u$ and $d$ quark momentum fractions in the proton.

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The ATLAS Collaboration. 2011-03-15. Measurement of the $W$ Charge Asymmetry in the $W \rightarrow \mu\nu$ Decay Mode in $pp$ Collisions at $\sqrt{s} = 7$ TeV with the ATLAS detector. https://doi.org/10.1016/j.physletb.2011.05.024

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