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arXiv · 2108.02070

JAM small-$x$ helicity phenomenology

Daniel Adamiak
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Abstract

We present the first-ever description the world data on the $g_1^{p,n}$ structure function at small Bjorken $x$ using evolution equations in $x$ derived from first principles QCD. This is a Monte-Carlo analysis within the JAM global framework that allows us to fit all existing polarized DIS data below $x<0.1$ as well as predict future measurements of small $x$ $g_1^{p,n}$ at the EIC. This is a necessary step in determining the quark helicity PDFs and, ultimately, the quark contribution to the proton spin.

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Daniel Adamiak. 2021-08-04. JAM small-$x$ helicity phenomenology. https://arxiv.org/abs/2108.02070

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