HAL will be down for maintenance from Friday, June 10 at 4pm through Monday, June 13 at 9am. More information
Skip to Main content Skip to Navigation
Journal articles

A model for halo formation with axion mixed dark matter

Abstract : There are several issues to do with dwarf galaxy predictions in the standard Λ cold dark matter (ΛCDM) cosmology that have suscitated much recent debate about the possible modification of the nature of dark matter as providing a solution. We explore a novel solution involving ultralight axions that can potentially resolve the missing satellites problem, the cusp-core problem and the `too big to fail' problem. We discuss approximations to non-linear structure formation in dark matter models containing a component of ultralight axions across four orders of magnitude in mass, 10-24 ≲ ma ≲ 10-20 eV, a range too heavy to be well constrained by linear cosmological probes such as the cosmic microwave background and matter power spectrum, and too light/non-interacting for other astrophysical or terrestrial axion searches. We find that an axion of mass ma ≈ 10-21 eV contributing approximately 85 per cent of the total dark matter can introduce a significant kpc scale core in a typical Milky Way satellite galaxy in sharp contrast to a thermal relic with a transfer function cut off at the same scale, while still allowing such galaxies to form in significant number. Therefore, ultralight axions do not suffer from the Catch 22 that applies to using a warm dark matter as a solution to the small-scale problems of CDM. Our model simultaneously allows formation of enough high-redshift galaxies to allow reconciliation with observational constraints, and also reduces the maximum circular velocities of massive dwarfs so that baryonic feedback may more plausibly resolve the predicted overproduction of massive Milky Way Galaxy dwarf satellites.
Complete list of metadata

https://hal-insu.archives-ouvertes.fr/insu-03645744
Contributor : Hal Sorbonne Université Gestionnaire Connect in order to contact the contributor
Submitted on : Friday, April 22, 2022 - 4:32:06 PM
Last modification on : Thursday, May 12, 2022 - 6:22:03 PM

File

stt2079.pdf
Publisher files allowed on an open archive

Identifiers

Citation

David J. E. Marsh, Joseph Silk. A model for halo formation with axion mixed dark matter. Monthly Notices of the Royal Astronomical Society, Oxford University Press (OUP): Policy P - Oxford Open Option A, 2014, 437, pp.2652-2663. ⟨10.1093/mnras/stt2079⟩. ⟨insu-03645744⟩

Share

Metrics

Record views

20

Files downloads

1