Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Probing Cold Dark Matter Cusps by Gravitational Lensing   I elaborate on my prediction that an indirect detection of cold dark matter
(CDM) may be possible by observing the gravitational lensing effects of the CDM
cusp caustics at cosmological distances. Cusps in the distribution of CDM are
plentiful once density perturbations enter the nonlinear regime of structure
formation. Caustic ring model of galactic halo formation provides a well
defined density profile and geometry near the cusps of the caustic rings. I
calculate the gravitational lensing effects of the cusps in this model. As a
pointlike background source passes behind a cusp of a cosmological foreground
halo, the magnification in its image may be detected by present instruments.
Depending on the strength of detected effect and the time scale of brightness
change, it may even be possible to discriminate between the CDM candidates:
axions and weakly interacting massive particles.

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The categories of this paper are: funct-an
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The categories of this paper are: supr-con
13
The categories of this paper are: quant-ph
3
The categories of this paper are: physics
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The categories of this paper are: acc-phys
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The categories of this paper are: patt-sol
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The categories of this paper are: plasm-ph
14
The categories of this paper are: math-ph
9
The categories of this paper are: nlin
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The categories of this paper are: chem-ph
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The categories of this paper are: atom-ph
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The categories of this paper are: adap-org
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The categories of this paper are: nucl-th
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The categories of this paper are: hep-lat
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The categories of this paper are: q-alg
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The categories of this paper are: mtrl-th