Formation of Milky Way-type stellar haloes in a Λ-CDM cosmology
Recent observations suggest that the Milky Way stellar halo has a ‘dual nature’, meaning that both dissipational and dissipationless processes play a role in its build-up. The GIMIC suite of cosmological hydro-dynamical simulations show that, for Milky Way-mass haloes, in situ star formation is the...
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| Format: | Article |
| Language: | English |
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EDP Sciences
2012-02-01
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| Series: | EPJ Web of Conferences |
| Online Access: | http://dx.doi.org/10.1051/epjconf/20121901002 |
| _version_ | 1818900156548907008 |
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| author | Font A.S. |
| author_facet | Font A.S. |
| author_sort | Font A.S. |
| collection | DOAJ |
| description | Recent observations suggest that the Milky Way stellar halo has a ‘dual nature’, meaning that both dissipational and dissipationless processes play a role in its build-up. The GIMIC suite of cosmological hydro-dynamical simulations show that, for Milky Way-mass haloes, in situ star formation is the dominant factor in the inner < 20 − 30 kpc, while tidal disruption of satellite galaxies contributes primarily to the outer regions. The in situ stars are found to originate in the earlier disc, at redshifts ~ 1– 1.5, and subsequently diffusing out of the disc by dynamical heating associated with mergers. The in situ component has a more flattened shape, a net prograde rotation and more metal-rich populations, in quantitative agreement with the observations. We conclude that the dual nature of the stellar halo is entirely compatible with the currently favoured Λ-CDM model. |
| first_indexed | 2024-12-19T19:59:23Z |
| format | Article |
| id | doaj.art-35866df86b80414284b6757ac86eda13 |
| institution | Directory Open Access Journal |
| issn | 2100-014X |
| language | English |
| last_indexed | 2024-12-19T19:59:23Z |
| publishDate | 2012-02-01 |
| publisher | EDP Sciences |
| record_format | Article |
| series | EPJ Web of Conferences |
| spelling | doaj.art-35866df86b80414284b6757ac86eda132022-12-21T20:07:42ZengEDP SciencesEPJ Web of Conferences2100-014X2012-02-01190100210.1051/epjconf/20121901002Formation of Milky Way-type stellar haloes in a Λ-CDM cosmologyFont A.S.Recent observations suggest that the Milky Way stellar halo has a ‘dual nature’, meaning that both dissipational and dissipationless processes play a role in its build-up. The GIMIC suite of cosmological hydro-dynamical simulations show that, for Milky Way-mass haloes, in situ star formation is the dominant factor in the inner < 20 − 30 kpc, while tidal disruption of satellite galaxies contributes primarily to the outer regions. The in situ stars are found to originate in the earlier disc, at redshifts ~ 1– 1.5, and subsequently diffusing out of the disc by dynamical heating associated with mergers. The in situ component has a more flattened shape, a net prograde rotation and more metal-rich populations, in quantitative agreement with the observations. We conclude that the dual nature of the stellar halo is entirely compatible with the currently favoured Λ-CDM model.http://dx.doi.org/10.1051/epjconf/20121901002 |
| spellingShingle | Font A.S. Formation of Milky Way-type stellar haloes in a Λ-CDM cosmology EPJ Web of Conferences |
| title | Formation of Milky Way-type stellar haloes in a Λ-CDM cosmology |
| title_full | Formation of Milky Way-type stellar haloes in a Λ-CDM cosmology |
| title_fullStr | Formation of Milky Way-type stellar haloes in a Λ-CDM cosmology |
| title_full_unstemmed | Formation of Milky Way-type stellar haloes in a Λ-CDM cosmology |
| title_short | Formation of Milky Way-type stellar haloes in a Λ-CDM cosmology |
| title_sort | formation of milky way type stellar haloes in a λ cdm cosmology |
| url | http://dx.doi.org/10.1051/epjconf/20121901002 |
| work_keys_str_mv | AT fontas formationofmilkywaytypestellarhaloesinalcdmcosmology |