CJ15 global PDF analysis with new electroweak data from the STAR and SeaQuest experiments

TL;DR

This paper updates the CJ global analysis of parton distribution functions by incorporating new electroweak data from STAR and SeaQuest experiments, enhancing quark flavor separation insights.

Contribution

It introduces new constraints on light quark and antiquark distributions at large x through recent experimental data, improving the accuracy of PDF flavor asymmetry modeling.

Findings

Enhanced constraints on light quark distributions near the valence region.

Extended large-x coverage of antiquark distributions.

Insights into the flavor asymmetry of the light antiquark sea.

Abstract

We present updates to a recent CTEQ-Jefferson Lab (CJ) global analysis of parton distribution functions with a new set of electroweak data that provide unique access to quark flavor separation in the proton. In particular, recent $W$ and $Z$ boson measurements from the STAR experiment at RHIC put additional constraints on light quarks and antiquarks near the valence regime. The new measurement of the Drell-Yan lepton pair production ratio in $p+p$ and $p+d$ collisions by the SeaQuest experiment at Fermilab extends the large-$x$ coverage of the previous E866 experiment and sheds new light on the light antiquarks distribution. In this report, the impact of these new data sets on parton distribution functions will be presented with emphasis given to the flavor asymmetry of the light antiquark sea at large values of the parton momentum $x$.