تقرير
Discy dwarf disruption and the shape of the Galactic halo
| العنوان: | Discy dwarf disruption and the shape of the Galactic halo |
|---|---|
| المؤلفون: | Gibbons, S. L. J., Belokurov, V., Erkal, D., Evans, N. W. |
| سنة النشر: | 2016 |
| المجموعة: | Astrophysics |
| مصطلحات موضوعية: | Astrophysics - Astrophysics of Galaxies |
| الوصف: | The shape of the Galactic dark halo can, in principle, be inferred through modelling of stellar tidal streams in the Milky Way halo. The brightest and the longest of these, the Sagittarius stream, reaches out to large Galactocentric distances and hence can deliver the tightest constraints on the Galaxy's potential. In this contribution, we revisit the idea that the Sagittarius Stream was formed from a rotating progenitor. We demonstrate that the angle between the disk's angular momentum and the progenitor's orbital angular momentum does not remain constant throughout the disruption. Instead, it undergoes a dramatic evolution caused, in part, by the changes in the progenitor's moment of inertia tensor. We show that, even in a spherical potential, the streams produced as a result of a disky dwarf disruption appear to be "precessing". Yet, this debris plane evolution is illusory as it is solely caused by the swaying and wobbling of the progenitor's disk. Stream plane precession is therefore not an unambiguous indicator of asphericity of the dark halo. Comment: 5 pages, 5 figures. Updated title to match published version. This is a pre-copyedited, author-produced version of an article accepted for publication in MNRAS following peer review |
| نوع الوثيقة: | Working Paper |
| DOI: | 10.1093/mnrasl/slw018 |
| URL الوصول: | http://arxiv.org/abs/1601.07720 |
| رقم الأكسشن: | edsarx.1601.07720 |
| قاعدة البيانات: | arXiv |
| DOI: | 10.1093/mnrasl/slw018 |
|---|