Strong Constraints on Fuzzy Dark Matter from Ultrafaint Dwarf Galaxy Eridanus II
| Autor: | Jens C. Niemeyer, David J. E. Marsh |
|---|---|
| Rok vydání: | 2019 |
| Předmět: |
Physics
Cosmology and Nongalactic Astrophysics (astro-ph.CO) Milky Way Dark matter FOS: Physical sciences General Physics and Astronomy Astrophysics Astrophysics::Cosmology and Extragalactic Astrophysics 01 natural sciences Astrophysics - Astrophysics of Galaxies Gravitation High Energy Physics - Phenomenology High Energy Physics - Phenomenology (hep-ph) Star cluster Astrophysics of Galaxies (astro-ph.GA) 0103 physical sciences Bosonic field Matter wave Eridanus 010306 general physics Dwarf galaxy Astrophysics - Cosmology and Nongalactic Astrophysics |
| Zdroj: | Physical review letters. 123(5) |
| ISSN: | 1079-7114 |
| Popis: | The fuzzy dark matter (FDM) model treats DM as a bosonic field with astrophysically large de Broglie wavelength. A striking feature of this model is $\mathcal{O}(1)$ fluctuations in the dark matter density on time scales which are shorter than the gravitational timescale. Including for the first time the effect of core oscillations, we demonstrate how such fluctuations lead to heating of star clusters, and thus an increase in their size over time. From the survival of the old star cluster in Eridanus II we infer $m_a\gtrsim 0.6\rightarrow 1\times 10^{-19}\text{ eV}$ within modelling uncertainty if FDM is to compose all of the DM, and derive constraints on the FDM fraction at lower masses. The subhalo mass function in the Milky Way implies $m_a\gtrsim 0.8\times 10^{-21}\text{ eV}$ to successfully form Eridanus II. The window between $10^{-21}\text{ eV}\lesssim m_a\lesssim 10^{-20}\text{ eV}$ is affected by narrow band resonances, and the limited applicability of the diffusion approximation. Some of this window may be consistent with observations of Eridanus II and more detailed investigations are required. 6 pages, 2 figures; v2 comments and clarifications added, matches version accepted for publication in PRL |
| Databáze: | OpenAIRE |
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