skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Structure formation constraints on Sommerfeld-enhanced dark matter annihilation

Abstract

We study the growth of cosmic structure in a ΛCDM universe under the assumption that dark matter self-annihilates with an averaged cross section times relative velocity that grows with the scale factor, an increase known as Sommerfeld-enhancement. Such an evolution is expected in models in which a light force carrier in the dark sector enhances the annihilation cross section of dark matter particles, and has been invoked, for instance, to explain anomalies in cosmic ray spectra reported in the past. In order to make our results as general as possible, we assume that dark matter annihilates into a relativistic species that only interacts gravitationally with the standard model. This assumption also allows us to test whether the additional relativistic species mildly favored by cosmic-microwave background data could originate from dark matter annihilation. We do not find evidence for Sommerfeld-enhanced dark matter annihilation and derive the corresponding upper limits on the annihilation cross-section.

Authors:
Publication Date:
OSTI Identifier:
22279900
Resource Type:
Journal Article
Journal Name:
Journal of Cosmology and Astroparticle Physics
Additional Journal Information:
Journal Volume: 2012; Journal Issue: 12; Other Information: Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 1475-7516
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ANNIHILATION; COSMIC RADIATION; COSMOLOGICAL CONSTANT; COSMOLOGY; CROSS SECTIONS; ENERGY SPECTRA; EVOLUTION; LIMITING VALUES; NONLUMINOUS MATTER; RELATIVISTIC RANGE; RELICT RADIATION; STANDARD MODEL; UNIVERSE; VISIBLE RADIATION

Citation Formats

Armendariz-Picon, Cristian, and Neelakanta, Jayanth T., E-mail: armen@phy.syr.edu, E-mail: jtneelak@syr.edu. Structure formation constraints on Sommerfeld-enhanced dark matter annihilation. United States: N. p., 2012. Web. doi:10.1088/1475-7516/2012/12/009.
Armendariz-Picon, Cristian, & Neelakanta, Jayanth T., E-mail: armen@phy.syr.edu, E-mail: jtneelak@syr.edu. Structure formation constraints on Sommerfeld-enhanced dark matter annihilation. United States. https://doi.org/10.1088/1475-7516/2012/12/009
Armendariz-Picon, Cristian, and Neelakanta, Jayanth T., E-mail: armen@phy.syr.edu, E-mail: jtneelak@syr.edu. Sat . "Structure formation constraints on Sommerfeld-enhanced dark matter annihilation". United States. https://doi.org/10.1088/1475-7516/2012/12/009.
@article{osti_22279900,
title = {Structure formation constraints on Sommerfeld-enhanced dark matter annihilation},
author = {Armendariz-Picon, Cristian and Neelakanta, Jayanth T., E-mail: armen@phy.syr.edu, E-mail: jtneelak@syr.edu},
abstractNote = {We study the growth of cosmic structure in a ΛCDM universe under the assumption that dark matter self-annihilates with an averaged cross section times relative velocity that grows with the scale factor, an increase known as Sommerfeld-enhancement. Such an evolution is expected in models in which a light force carrier in the dark sector enhances the annihilation cross section of dark matter particles, and has been invoked, for instance, to explain anomalies in cosmic ray spectra reported in the past. In order to make our results as general as possible, we assume that dark matter annihilates into a relativistic species that only interacts gravitationally with the standard model. This assumption also allows us to test whether the additional relativistic species mildly favored by cosmic-microwave background data could originate from dark matter annihilation. We do not find evidence for Sommerfeld-enhanced dark matter annihilation and derive the corresponding upper limits on the annihilation cross-section.},
doi = {10.1088/1475-7516/2012/12/009},
url = {https://www.osti.gov/biblio/22279900}, journal = {Journal of Cosmology and Astroparticle Physics},
issn = {1475-7516},
number = 12,
volume = 2012,
place = {United States},
year = {2012},
month = {12}
}