Dwarf galaxies in CDM and SIDM with baryons: observational probes of the nature of dark matter
We present the first cosmological simulations of dwarf galaxies, which include dark matter self-interactions and baryons. We study two dwarf galaxies within cold dark matter, and four different elastic self-interacting scenarios with constant and velocity-dependent cross-sections, motivated by a new...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | en_US |
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Oxford University Press
2015
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| Online Access: | http://hdl.handle.net/1721.1/98452 https://orcid.org/0000-0001-8593-7692 |
| _version_ | 1826196221759324160 |
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| author | Vogelsberger, Mark Zavala, Jesus Simpson, Christine Jenkins, Adrian |
| author2 | Massachusetts Institute of Technology. Department of Physics |
| author_facet | Massachusetts Institute of Technology. Department of Physics Vogelsberger, Mark Zavala, Jesus Simpson, Christine Jenkins, Adrian |
| author_sort | Vogelsberger, Mark |
| collection | MIT |
| description | We present the first cosmological simulations of dwarf galaxies, which include dark matter self-interactions and baryons. We study two dwarf galaxies within cold dark matter, and four different elastic self-interacting scenarios with constant and velocity-dependent cross-sections, motivated by a new force in the hidden dark matter sector. Our highest resolution simulation has a baryonic mass resolution of 1.8 × 10[superscript 2]M[subscript ⊙] and a gravitational softening length of 34 pc at z = 0. In this first study we focus on the regime of mostly isolated dwarf galaxies with halo masses ~ 10[superscript 10]M[subscript ⊙] where dark matter dynamically dominates even at sub-kpc scales. We find that while the global properties of galaxies of this scale are minimally affected by allowed self-interactions, their internal structures change significantly if the cross-section is large enough within the inner sub-kpc region. In these dark-matter-dominated systems, self-scattering ties the shape of the stellar distribution to that of the dark matter distribution. In particular, we find that the stellar core radius is closely related to the dark matter core radius generated by self-interactions. Dark matter collisions lead to dwarf galaxies with larger stellar cores and smaller stellar central densities compared to the cold dark matter case. The central metallicity within 1 kpc is also larger by up to ∼15 per cent in the former case. We conclude that the mass distribution and characteristics of the central stars in dwarf galaxies can potentially be used to probe the self-interacting nature of dark matter. |
| first_indexed | 2024-09-23T10:23:26Z |
| format | Article |
| id | mit-1721.1/98452 |
| institution | Massachusetts Institute of Technology |
| language | en_US |
| last_indexed | 2024-09-23T10:23:26Z |
| publishDate | 2015 |
| publisher | Oxford University Press |
| record_format | dspace |
| spelling | mit-1721.1/984522022-09-30T20:46:24Z Dwarf galaxies in CDM and SIDM with baryons: observational probes of the nature of dark matter Vogelsberger, Mark Zavala, Jesus Simpson, Christine Jenkins, Adrian Massachusetts Institute of Technology. Department of Physics MIT Kavli Institute for Astrophysics and Space Research Vogelsberger, Mark We present the first cosmological simulations of dwarf galaxies, which include dark matter self-interactions and baryons. We study two dwarf galaxies within cold dark matter, and four different elastic self-interacting scenarios with constant and velocity-dependent cross-sections, motivated by a new force in the hidden dark matter sector. Our highest resolution simulation has a baryonic mass resolution of 1.8 × 10[superscript 2]M[subscript ⊙] and a gravitational softening length of 34 pc at z = 0. In this first study we focus on the regime of mostly isolated dwarf galaxies with halo masses ~ 10[superscript 10]M[subscript ⊙] where dark matter dynamically dominates even at sub-kpc scales. We find that while the global properties of galaxies of this scale are minimally affected by allowed self-interactions, their internal structures change significantly if the cross-section is large enough within the inner sub-kpc region. In these dark-matter-dominated systems, self-scattering ties the shape of the stellar distribution to that of the dark matter distribution. In particular, we find that the stellar core radius is closely related to the dark matter core radius generated by self-interactions. Dark matter collisions lead to dwarf galaxies with larger stellar cores and smaller stellar central densities compared to the cold dark matter case. The central metallicity within 1 kpc is also larger by up to ∼15 per cent in the former case. We conclude that the mass distribution and characteristics of the central stars in dwarf galaxies can potentially be used to probe the self-interacting nature of dark matter. 2015-09-10T17:45:34Z 2015-09-10T17:45:34Z 2014-09 2014-08 Article http://purl.org/eprint/type/JournalArticle 0035-8711 1365-2966 http://hdl.handle.net/1721.1/98452 Vogelsberger, M., J. Zavala, C. Simpson, and A. Jenkins. “Dwarf Galaxies in CDM and SIDM with Baryons: Observational Probes of the Nature of Dark Matter.” Monthly Notices of the Royal Astronomical Society 444, no. 4 (September 15, 2014): 3684–3698. https://orcid.org/0000-0001-8593-7692 en_US http://dx.doi.org/10.1093/mnras/stu1713 Monthly Notices of the Royal Astronomical Society Creative Commons Attribution-Noncommercial-Share Alike http://creativecommons.org/licenses/by-nc-sa/4.0/ application/pdf Oxford University Press arXiv |
| spellingShingle | Vogelsberger, Mark Zavala, Jesus Simpson, Christine Jenkins, Adrian Dwarf galaxies in CDM and SIDM with baryons: observational probes of the nature of dark matter |
| title | Dwarf galaxies in CDM and SIDM with baryons: observational probes of the nature of dark matter |
| title_full | Dwarf galaxies in CDM and SIDM with baryons: observational probes of the nature of dark matter |
| title_fullStr | Dwarf galaxies in CDM and SIDM with baryons: observational probes of the nature of dark matter |
| title_full_unstemmed | Dwarf galaxies in CDM and SIDM with baryons: observational probes of the nature of dark matter |
| title_short | Dwarf galaxies in CDM and SIDM with baryons: observational probes of the nature of dark matter |
| title_sort | dwarf galaxies in cdm and sidm with baryons observational probes of the nature of dark matter |
| url | http://hdl.handle.net/1721.1/98452 https://orcid.org/0000-0001-8593-7692 |
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