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Parity-violating asymmetry of $W$ bosons produced in $p$-$p$ collisions

Xun Chen·Yajun Mao·Bo-Qiang Ma
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Abstract

The parity-violating asymmetry is an ideal tool to study the quark helicity distribution in the proton. We study the parity-violating asymmetry of $W^{\pm}$ bosons produced by longitudinally polarized $p$-$p$ collision in RHIC, based on predictions of quark distributions of the proton in the SU(6) quark-spectator-diquark model and a perturbative QCD based counting rule analysis. We find that the two models give nearly equal asymmetry for $W^+$ but that for $W^-$ quite different. Therefore future experiments on such quantity can help to clarify different predictions of the value $Δd(x)/d(x)$ at $x \to 1$ in the proton.

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Xun Chen, Yajun Mao, Bo-Qiang Ma. 2005-07-13. Parity-violating asymmetry of $W$ bosons produced in $p$-$p$ collisions. https://doi.org/10.1016/j.nuclphysa.2005.05.146

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