Abstract
We suggest that two-to-two dark matter fusion may be the relaxation process that resolves the small-scale structure problems of the cold collisionless dark matter paradigm. In order for the fusion cross section to scale correctly across many decades of astrophysical masses from dwarf galaxies to galaxy clusters, we require the fractional binding energy released to be greater than , where , 2 depends on local dark sector chemistry. The size of the dark-sector interaction cross sections must be barn, moderately larger than for standard model deuteron fusion, indicating a dark nuclear scale . Dark fusion firmly predicts constant below the characteristic velocities of galaxy clusters. Observations of the inner structure of galaxy groups with velocity dispersion of several hundred kilometers per second, of which a handful have been identified, could differentiate dark fusion from a dark photon model.
- Received 29 November 2017
- Revised 7 May 2018
DOI:https://doi.org/10.1103/PhysRevLett.120.221806
Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP3.
Published by the American Physical Society