Speaker
Christopher Cocuzza
(Temple University)
Description
We perform a global QCD analysis of unpolarized parton distributions within a Bayesian Monte Carlo framework, including the new $W$-lepton production data from the STAR Collaboration at RHIC and Drell-Yan di-muon data from the SeaQuest experiment at Fermilab. We assess the impact of these two new measurements on the light antiquark sea in the proton, and the $\bar{d}-\bar{u}$ asymmetry in particular. The SeaQuest data are found to significantly reduce the uncertainty on the $\bar{d}/\bar{u}$ ratio at large parton momentum fractions $x$, strongly favoring an enhanced $\bar d$ sea up to $x \approx 0.4$, in general agreement with nonperturbative calculations based on chiral symmetry breaking in QCD.
| Submitted on behalf of a Collaboration? | No |
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Authors
Andreas Metz
(Temple University)
Christopher Cocuzza
(Temple University)
Wally Melnitchouk
(Jefferson Lab)
nobuo sato
(jlab)
