Heating of galactic gas by dark matter annihilation in ultracompact minihalos

Hamish A. Clark, Nikolas Iwanus, Pascal J. Elahi, Geraint F. Lewis, Pat Scott

Research output: Contribution to journalArticlepeer-review

9 Citations (Scopus)


The existence of substructure in halos of annihilating dark matter would be expected to substantially boost the rate at which annihilation occurs. Ultracompact minihalos of dark matter (UCMHs) are one of the more extreme examples of this. The boosted annihilation can inject significant amounts of energy into the gas of a galaxy over its lifetime. Here we determine the impact of the boost factor from UCMH substructure on the heating of galactic gas in a Milky Way-type galaxy, by means of N-body simulation. If 1% of the dark matter exists as UCMHs, the corresponding boost factor can be of order 10(5). For reasonable values of the relevant parameters (annihilation cross section 3 x 10(-26) cm(3) s(-1), dark matter mass 100 GeV, 10% heating efficiency), we show that the presence of UCMHs at the 0.1% level would inject enough energy to eject significant amounts of gas from the halo, potentially preventing star formation within similar to 1 kpc of the halo centre.

Original languageEnglish
Article number048
Number of pages14
JournalJournal of Cosmology and Astroparticle Physics
Issue number5
Publication statusPublished - 25 May 2017


Dive into the research topics of 'Heating of galactic gas by dark matter annihilation in ultracompact minihalos'. Together they form a unique fingerprint.

Cite this