Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Measurement of the Proton Spin Structure Function $g_1(x,Q^2)$ for $Q^2$
  from 0.15 to 1.6 GeV$^2$ with CLAS   Double-polarization asymmetries for inclusive $ep$ scattering were measured
at Jefferson Lab using 2.6 and 4.3 GeV longitudinally polarized electrons
incident on a longitudinally polarized NH$_3$ target in the CLAS detector. The
polarized structure function $g_1(x,Q^2)$ was extracted throughout the nucleon
resonance region and into the deep inelastic regime, for $Q^2 = 0.15 -1.64
$GeV$^2$. The contributions to the first moment $\Gamma_1(Q^2) = \int
g_1(x,Q^2)dx$ were determined up to $Q^2=1.2$ GeV$^2$. Using a parametrization
for $g_1$ in the unmeasured low $x$ regions, the complete first moment was
estimated over this $Q^2$ region. A rapid change in $\Gamma_1$ is observed for
$Q^2 < 1 $GeV$^2$, with a sign change near $Q^2 = 0.3 $GeV$^2$, indicating
dominant contributions from the resonance region. At $Q^2=1.2$ GeV$^2$ our data
are below the pQCD evolved scaling value.

19
The categories of this paper are: eess
33
The categories of this paper are: plasm-ph
4
The categories of this paper are: cond-mat
10
The categories of this paper are: q-bio
30
The categories of this paper are: q-alg
27
The categories of this paper are: comp-gas
2
The categories of this paper are: math
25
The categories of this paper are: patt-sol
29
The categories of this paper are: funct-an
20
The categories of this paper are: acc-phys
31
The categories of this paper are: ao-sci
21
The categories of this paper are: adap-org
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The categories of this paper are: chao-dyn
9
The categories of this paper are: nlin
5
The categories of this paper are: gr-qc
13
The categories of this paper are: quant-ph