2003/11/06 by E. I. Vorobyov, U. Klein, Yu. A. Shchekinov +1 · 1 citation
Engineering · Physics and Astronomy · #Astronomy and Astrophysical Research #Galaxies: Formation, Evolution, Phenomena #Space Technology and Applications #astro-ph
paper · pdf · doi:10.1051/0004-6361:20031523
published as Astron.Astrophys. 413 (2004) 939-948 · 11 pages, 11 figures, accepted for publication in Astronomy and Astrophysics
arxiv created 2003/11/06 · openalex publication_date 2004/01/01 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/01
Numerical hydrodynamical modelling of supernova-driven shell formation is performed with a purpose to reproduce a giant HI ring (diameter 1.7 kpc) in the dwarf irregular galaxy Holmberg I (Ho I). We find that the contrast in HI surface density between the central HI depression and the ring is sensitive to the shape of the gravitational potential. This circumstance can be used to constrain the total mass (including the dark matter halo) of nearly face-on dwarf irregulars. We consider two models of Ho I, which differ by an assumed mass of the dark matter halo Mh. The contrast in HI surface density between the central HI depression and the ring, as well as the lack of gas expansion in the central hole, are better reproduced by the model with a massive halo of than by that with a small halo of , implying that Ho I is halo-dominated. Assuming the halo mass of , we determine the mechanical energy required to form the observed ring equal to ergs, equivalent Type II supernovae. The inclination of Ho I is constrained to by comparing the modelled HI spectrum and channel maps with those observed.