تقرير
Major Substructure in the M31 Outer Halo: the South-West Cloud
| العنوان: | Major Substructure in the M31 Outer Halo: the South-West Cloud |
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| المؤلفون: | Bate, N. F., Conn, A. R., McMonigal, B., Lewis, G. F., Martin, N. F., McConnachie, A. W., Veljanoski, J., Mackey, A. D., Ferguson, A. M. N., Ibata, R. A., Irwin, M. J., Fardal, M., Huxor, A. P., Babul, A. |
| سنة النشر: | 2013 |
| المجموعة: | Astrophysics |
| مصطلحات موضوعية: | Astrophysics - Astrophysics of Galaxies |
| الوصف: | We undertake the first detailed analysis of the stellar population and spatial properties of a diffuse substructure in the outer halo of M31. The South-West Cloud lies at a projected distance of ~100 kpc from the centre of M31, and extends for at least ~50 kpc in projection. We use Pan-Andromeda Archaeological Survey photometry of red giant branch stars to determine a distance to the South-West Cloud of 793 +/- 45 kpc. The metallicity of the cloud is found to be [Fe/H] = -1.3 +/- 0.1. This is consistent with the coincident globular clusters PAndAS-7 and PAndAS-8, which have metallicities determined using an independent technique of [Fe/H] = -1.35 +/- 0.15. We measure a brightness for the Cloud of M_V = -12.1 mag; this is ~75 per cent of the luminosity implied by the luminosity-metallicity relation. Under the assumption that the South-West Cloud is the visible remnant of an accreted dwarf satellite, this suggests that the progenitor object was amongst M31's brightest dwarf galaxies prior to disruption. Comment: 13 pages, 9 figures, accepted for publication in MNRAS |
| نوع الوثيقة: | Working Paper |
| DOI: | 10.1093/mnras/stt2139 |
| الوصول الحر: | http://arxiv.org/abs/1311.0906Test |
| رقم الانضمام: | edsarx.1311.0906 |
| قاعدة البيانات: | arXiv |
| DOI: | 10.1093/mnras/stt2139 |
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