Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Axion Condensate Dark Matter Constraints from Resonant Enhancement of
  Background Radiation   We investigate the possible parametric growth of photon amplitudes in a
background of axion-like particle (ALP) dark matter. The observed extragalactic
background radiation limits the allowed enhancement effect. We derive the
resulting constraints on the axion-photon coupling constant $g_{a\gamma}$ from
Galactic ALP condensates as well as over-densities. If ALP condensates of size
$R$ exist in our Galaxy, a scan for extremely narrow unresolved spectral lines
with frequency $\nu$ can constrain the axion-photon coupling at ALP mass
$m_a=4\pi\nu$ to $g_{a\gamma}\lesssim2\times10^{-14}(10\,{\rm kpc}/R)\,{\rm
GeV}^{-1}$. Radio to optical background data yield constraints at this level
within observed wavebands or ALP mass windows over a broad range $0.08\, \mu
\text{eV} \lesssim m_a \lesssim 8 \text{ eV}$. These condensate constraints on
$g_{a\gamma}$ probe down to the QCD axion band for $m_a \gtrsim$ 10 $\mu$eV.

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The categories of this paper are: atom-ph
10
The categories of this paper are: q-bio
26
The categories of this paper are: bayes-an
17
The categories of this paper are: q-fin
1
The categories of this paper are: cs
12
The categories of this paper are: nucl-th
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The categories of this paper are: stat
5
The categories of this paper are: gr-qc
21
The categories of this paper are: adap-org
27
The categories of this paper are: comp-gas
7
The categories of this paper are: hep-th
22
The categories of this paper are: chao-dyn
9
The categories of this paper are: nlin
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The categories of this paper are: q-alg
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The categories of this paper are: chem-ph
28
The categories of this paper are: alg-geom