Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Constraints on nuclear gluon densities from J/psi data   The gluon density in nuclei, G^A(x), is poorly constrained at all x from the
current DIS and Drell-Yan data. In this paper, we point out that J/psi
production measured in proton-nucleus collisions at sqrt(s)=38.8 GeV by the
E866 collaboration puts stringent constraints on the x-dependence of the
G^W/G^Be ratio in the x=0.02-0.1 range. The E866 data suggest a rather mild
x-dependence of G^W/G^Be, and consequently tend to favour DS and HKM sets,
rather than the DSg, EKS, and EPS parametrizations which exhibit a large
shadowing and anti-shadowing.

29
The categories of this paper are: funct-an
35
The categories of this paper are: mtrl-th
26
The categories of this paper are: bayes-an
16
The categories of this paper are: stat
31
The categories of this paper are: ao-sci
37
The categories of this paper are: supr-con
4
The categories of this paper are: cond-mat
22
The categories of this paper are: chao-dyn
25
The categories of this paper are: patt-sol
17
The categories of this paper are: q-fin
11
The categories of this paper are: hep-lat
6
The categories of this paper are: astro-ph
24
The categories of this paper are: dg-ga
23
The categories of this paper are: solv-int
1
The categories of this paper are: cs
7
The categories of this paper are: hep-th