Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Consistent explanation for the cosmic-ray positron excess in $p$-wave
  Breit-Wigner enhanced dark matter annihilation   Dark matter (DM) annihilation in the galactic halo can be enhanced relative
to that in the early Universe due to the Breit-Wigner enhancement, if the DM
particles annihilate through a narrow resonance. Although the $s$-wave
Breit-Wigner enhancement can provide a consistent explanation for both the
observed cosmic-ray (CR) positron excess and the DM thermal relic density, it
is severely constrained by the observations of gamma rays from dwarf spheroidal
satellite galaxies (dSphs) and the cosmic microwave background (CMB), which
have relatively lower allowed DM annihilation cross section and typical DM
velocities than that in the galactic halo. Furthermore, in the $s$-wave
Breit-Wigner enhancement, the case where the resonance mass is below a
threshold (twice the DM mass) is ruled out due to the monotonically increasing
annihilation cross section with decreasing DM velocity. In this work, we
consider Breit-Wigner enhanced $p$-wave DM annihilation. We explore the
parameter regions which can simultaneously account for the CR positron excess
and DM thermal relic density without violating the constraints from dSphs gamma
rays and CMB. We show that the velocity-dependent cross section in this
scenario can peak around the typical DM velocity in the galactic halo for the
resonance mass both above and below the threshold. Moreover, the highly
suppressed annihilation cross section at extremely low DM velocity can evade
the constraints from dSphs gamma rays and CMB easily, which results in larger
allowed parameter regions than that in the $s$-wave case.

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The categories of this paper are: chem-ph
7
The categories of this paper are: hep-th
4
The categories of this paper are: cond-mat
6
The categories of this paper are: astro-ph
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The categories of this paper are: dg-ga
11
The categories of this paper are: hep-lat
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The categories of this paper are: econ
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The categories of this paper are: supr-con
13
The categories of this paper are: quant-ph
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The categories of this paper are: comp-gas
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The categories of this paper are: acc-phys
23
The categories of this paper are: solv-int
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The categories of this paper are: ao-sci
5
The categories of this paper are: gr-qc
14
The categories of this paper are: math-ph
1
The categories of this paper are: cs