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arXiv · 2108.01029

Measurements of $W$ and $Z/\gamma^*$ cross sections and their ratios in $pp$ collisions at STAR

Jae Nam
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Abstract

While the unpolarized parton distribution functions of the valence quarks ($d$ and $u$) are well determined from DIS experiments, the sea quark counterparts, $\bar{d}$ and $\bar{u}$, are much less constrained, in particular, near the valence region. Measurements of $W^+/W^-$ production ratio in $pp$ collider experiments, such as the STAR experiment at RHIC, can probe the $\bar{d}/\bar{u}$ ratio at a large $Q^2$ set by the $W$ mass. These proceedings will discuss recent results of $W$ and $Z$ cross-section measurements using the STAR $pp$ collision data at a center-of-mass energy of $\sqrt{s} = 500/510\;\mathrm{GeV}$ collected in 2011, 2012, 2013 and 2017.

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Jae Nam. 2021-08-02. Measurements of $W$ and $Z/\gamma^*$ cross sections and their ratios in $pp$ collisions at STAR. https://arxiv.org/abs/2108.01029

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