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arXiv · 1012.4535

Measurement of Longitudinal Spin Asymmetries From $W\rightarrow e$ Boson Decay in Polarized pp Collisions at $\sqrt{s}=500$ GeV at RHIC-PHENIX

Kensuke Okada et al.
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Abstract

We report the measurement of the parity violating single spin asymmetries for inclusive high transverse momentum electrons and positrons in polarized $p+p$ collisions at a center of mass energy of $\sqrt{s}=500$ GeV with the PHENIX detector at RHIC. These electrons are attributed to the decay of $W^\pm$ and $Z^0$ bosons, and measured production cross section is consistent with the expectations. The $W$ production is confirmed for the first time in $p+p$ collisions. Its spin asymmetry in the polarized $p+p$ collisions is a important probe for the quark flavor decomposition of the proton spin.

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Kensuke Okada et al.. 2010-12-21. Measurement of Longitudinal Spin Asymmetries From $W\rightarrow e$ Boson Decay in Polarized pp Collisions at $\sqrt{s}=500$ GeV at RHIC-PHENIX. https://doi.org/10.1088/1742-6596%2F295%2F1%2F012072

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