Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: How to probe the spin-dependent gluon distributions   Two-spin asymmetries $A_{LL}^{\pi^0}$ are calculated for various types of
spin-dependent gluon distributions. It is concluded that the E581/704 data on
$A_{LL}^{\pi^0}$ do not necessarily rule out the large gluon polarization but
restrict severely the $x$ dependence of its distribution. Moreover,
$A_{LL}^{J/\psi}$ are calculated for the forthcoming test of spin-dependent
gluon distributions.

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The categories of this paper are: astro-ph
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The categories of this paper are: q-fin
29
The categories of this paper are: funct-an
24
The categories of this paper are: dg-ga
8
The categories of this paper are: hep-ex
21
The categories of this paper are: adap-org
18
The categories of this paper are: econ
9
The categories of this paper are: nlin
13
The categories of this paper are: quant-ph
30
The categories of this paper are: q-alg
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The categories of this paper are: gr-qc
36
The categories of this paper are: cmp-lg
35
The categories of this paper are: mtrl-th
2
The categories of this paper are: math
37
The categories of this paper are: supr-con
14
The categories of this paper are: math-ph