Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Bremsstrahlung and Gamma Ray Lines in 3 Scenarios of Dark Matter
  Annihilation   Gamma ray spectral features are of interest for indirect searches of dark
matter (DM). Following Barger et al, we consider 3 simple scenarios of DM that
annihilates into Standard Model (SM) fermion pairs. Scenario 1 is a Majorana DM
candidate coupled to a charged scalar, scenario 2 is a Majorana DM coupled to a
charged gauge boson and scenario 3 is a real scalar DM coupled a charged
vector-like fermion. As shown by Barger et al, these 3 scenarios share
precisely the same internal Bremsstrahlung spectral signature into gamma rays.
Their phenomenology is however distinct. In particular for annihilation into
light SM fermions, in the chiral limit, the 2-body annihilation cross section
is p-wave suppressed for the Majorana candidates while it is d-wave suppressed
for the real scalar. In the present work we study the annihilation into 2
gammas, showing that these three scenarios have distinct, and so potentially
distinguishable, spectral signatures into gamma rays. In the case of the real
scalar candidate we provide a new calculation of the amplitude for annihilation
into 2 gammas.

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The categories of this paper are: q-alg
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The categories of this paper are: patt-sol
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The categories of this paper are: eess
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The categories of this paper are: chao-dyn
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The categories of this paper are: plasm-ph
1
The categories of this paper are: cs
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The categories of this paper are: nucl-ex
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The categories of this paper are: nucl-th
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The categories of this paper are: chem-ph
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The categories of this paper are: alg-geom
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The categories of this paper are: q-fin
3
The categories of this paper are: physics
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The categories of this paper are: econ
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The categories of this paper are: dg-ga
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The categories of this paper are: ao-sci
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The categories of this paper are: hep-th