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arXiv · 0707.0060

Global reanalysis of nPDFs

K. J. Eskola·V. J. Kolhinen·H. Paukkunen·C. A. Salgado
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Abstract

In this talk, we present the results from our recent global reanalysis of nuclear parton distribution functions (nPDFs), where the DGLAP-evolving nPDFs are constrained by nuclear hard process data from deep inelastic $l+A$ scattering (DIS) and the Drell-Yan (DY) process in $p+A$ collisions, and by sum rules. The main improvements over our earlier work {\em EKS98} are the automated $χ^2$ minimization, better controllable fit functions and possibility for error estimates. The obtained 16-parameter fit to N=514 datapoints is good, $χ^2/{\rm d.o.f}=0.82$. Fit quality comparison and the error estimates obtained show that the old {\em EKS98} parametrization is fully consistent with the present automated reanalysis. Comparison with other global nPDF analyses is presented as well. Within the DGLAP framework we also discuss the possibility of incorporating a clearly stronger gluon shadowing, which is suggested by the RHIC BRAHMS data from d+Au collisions.

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K. J. Eskola, V. J. Kolhinen, H. Paukkunen, C. A. Salgado. 2007-06-30. Global reanalysis of nPDFs. https://arxiv.org/abs/0707.0060

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