Astrophysical Seminar (28 April 2016, 11:00)Опубликовано: 21/04/2016
Speaker: E.V. Polyachenko (INASAN)
Title: “Bar formation in galaxies with cuspy bulges”
We suggest a solution for a problem of bar formation in galaxies with cuspy bulges, e.g., the Milky Way galaxy. The problem is connected with the presence of a so-called inner Lindblad resonance (ILR), which exists for any possible pattern speed of the bar. From theoretical point of view, ILR prevents bar formation, although N-body experiments show bar development by usual bar instability during 3 Gyr. A possible reason is due to the initial disc thickness, to which the pattern speed and orbit resonances are very sensitive. Accounting for the disc thickness in a toy model allows us to reproduce the bar mode by a global mode analysis in the framework of linear perturbation theory.