Volume 388, Number 3, June IV 2002
|Page(s)||766 - 770|
|Section||Cosmology (including clusters of galaxies)|
|Published online||10 June 2002|
Dynamical modeling of the stellar nucleus of M 31
Inter–University Centre for Astronomy and Astrophysics, Ganeshkhind, Pune 411 007, India
Corresponding author: N. Sambhus, firstname.lastname@example.org
Accepted: 27 February 2002
We present stellar dynamical models of the lopsided, double–peaked nucleus of M 31, derived from Hubble Space Telescope (HST) photometry. A Schwarzschild–type method, in conjunction with Richardson–Lucy deconvolution, was employed to construct steadily rotating, hot, stellar disks. The stars orbit a massive dark object, on prograde and retrograde quasi–periodic loop orbits. Our results support Tremaine's eccentric disk model, extended to include a more massive disk, non zero pattern speed (Ω), and different viewing angle. Most of the disk mass populated prograde orbits, with 3.4% on retrograde orbits. The best fits to photometric and kinematic maps were disks with . We speculate on the origins of the lopsidedness, invoking recent work on the linear overstability of nearly Keplerian disks, that possess even a small amount of a counter – rotating component. Accretion of material – no more massive than a globular cluster – onto a preexisting stellar disk, will account for the mass in our retrograde orbits, and could have stimulated the lopsidedness seen in the nucleus of M 31.
Key words: galaxies: individual: M 31 / galaxies: kinematics and dynamics / galaxies: nuclei
© ESO, 2002
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.