Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Selection Rule for Enhanced Dark Matter Annihilation   We point out a selection rule for enhancement (suppression) of odd (even)
partial waves of dark matter coannihilation or annihilation using Sommerfeld
effect. Using this, the usually velocity-suppressed p-wave annihilation can
dominate the annihilation signals in the present Universe. The selection
mechanism is a manifestation of the exchange symmetry of identical incoming
particles, and generic for multi-state DM with off-diagonal long-range
interactions. As a consequence, the relic and late-time annihilation rates are
parametrically different and a distinctive phenomenology, with large but
strongly velocity-dependent annihilation rates, is predicted.

36
The categories of this paper are: cmp-lg
3
The categories of this paper are: physics
8
The categories of this paper are: hep-ex
13
The categories of this paper are: quant-ph
5
The categories of this paper are: gr-qc
20
The categories of this paper are: acc-phys
35
The categories of this paper are: mtrl-th
19
The categories of this paper are: eess
10
The categories of this paper are: q-bio
14
The categories of this paper are: math-ph
37
The categories of this paper are: supr-con
15
The categories of this paper are: nucl-ex
22
The categories of this paper are: chao-dyn
11
The categories of this paper are: hep-lat
17
The categories of this paper are: q-fin
32
The categories of this paper are: atom-ph