Title: Enabling forbidden dark matter

Abstract

The thermal relic density of dark matter is conventionally set by two-body annihilations. We point out that in many simple models, 3 → 2 annihilations can play an important role in determining the relic density over a broad range of model parameters. This occurs when the two-body annihilation is kinematically forbidden, but the 3 → 2 process is allowed; we call this scenario not-forbidden dark matter. We illustrate this mechanism for a vector-portal dark matter model, showing that for a dark matter mass of m _χ ~ MeV-10 GeV, 3 → 2 processes not only lead to the observed relic density, but also imply a selfinteraction cross section that can solve the cusp/core problem. This can be accomplished while remaining consistent with stringent CMB constraints on light dark matter, and can potentially be discovered at future direct detection experiments.

Authors:

Cline, James M. ^[1]; Liu, Hongwan ^[2]; Slatyer, Tracy R. ^[2]; Xue, Wei ^[2]

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+ Show Author Affiliations

1. European Organization for Nuclear Research (CERN), Geneva (Switzerland); Rue Univ., Montreal, QC (Canada)
2. Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)

Publication Date:

2017-10-20

Research Org.:

Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)

Sponsoring Org.:

USDOE Office of Science (SC)

OSTI Identifier:

1400426

Alternate Identifier(s):

OSTI ID: 1503863

Grant/Contract Number:  

SC0013999; SC00012567

Resource Type:

Published Article

Journal Name:

Physical Review D

Additional Journal Information:

Journal Volume: 96; Journal Issue: 8; Journal ID: ISSN 2470-0010

Publisher:

American Physical Society (APS)

Country of Publication:

United States

Language:

English

Subject:

79 ASTRONOMY AND ASTROPHYSICS