1995/03/05 by Héctor Velázquez, H. Velazquez, S. D. M. White +1 · 5 citations
Physics and Astronomy · #Astronomy #Astrophysics #Dwarf galaxy #Dwarf spheroidal galaxy #Galactic halo #Galaxies: Formation, Evolution, Phenomena #Galaxy #Galaxy rotation curve #Halo #Interacting galaxy #Milky Way #Physics #Population #Sagittarius #Scientific Research and Discoveries #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.1093/mnras/275.1.l23
8 pages, uuencoded compressed postscript file (4 figures are included). Submitted to MNRAS.
arxiv created 1995/03/05 · openalex publication_date 1995/07/01 · arxiv updated 2016/06/08 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We use numerical simulations to test the feasibility of the suggestion by Ibata, Gilmore & Irwin that the excess population of stars which they discovered in the Sagittarius region may be the disrupted remains of a dwarf spheroidal galaxy. We find that a Fornax-like model for the pre-disruption system can indeed reproduce the data. However, the galaxy must be on a relatively short-period orbit with a pericentre of about 10 kpc and an apocentre of about 52 kpc, giving a current transverse velocity of 255 km s−1 and a period of ~760 Myr. Furthermore, disruption must have occurred predominantly on the last pericentric passage rather than on the present one. The data are consistent with transverse motion either towards or away from the Galactic Plane. These results depend primarily on the rotation curve of the Galaxy and are insensitive to the mass distribution in its outer halo or to the mass of its disk.