Hydrodynamic simulations of the triaxial bulge of M 31
TLDR
In this article, the potential of the stellar bulge is derived from its surface brightness prole, which is assumed to be triaxial and rotating in the same plane as the disk in order to explain the twisted nature of M 31's central isophotes and the non circular gas velocities in the inner disk.Abstract:
The interstellar gas flow in the inner disk of M 31 is modelled using a new, two dimensional, grid based, hydrodynamics code. The potential of the stellar bulge is derived from its surface brightness prole. The bulge is assumed to be triaxial and rotating in the same plane as the disk in order to explain the twisted nature of M 31's central isophotes and the non circular gas velocities in the inner disk. Results are compared with CO observations and the bulge is found to be a fast rotator with a B-band mass-to-light ratio, B =6 .5 0.8, and a ratio of co-rotation radius to bulge semi-major axis,R =1 .2 0.1, implying that any dark halo must have a low density core in contradiction to the predictions of CDM. These conclusions would be strengthened by further observations conrming the model's o axis CO velocity predictions.read more
Citations
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Journal ArticleDOI
Structural properties of disk galaxies. II. Intrinsic shape of bulges
TL;DR: In this article, the intrinsic shape of S0-Sb galaxies was derived based on the geometrical relationship between the apparent and intrinsic shapes of bulges and disks, and the authors found that a large fraction of them are characterized by an elliptical section (B/A 2) or equivalently by the bulges of galaxies with a bulge-to-total ratio B/T>0.3.
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Minor-axis velocity gradients in disk galaxies
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Self-Gravitating Eccentric Disk Models for the Double Nucleus of M31
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The Intrinsic Shape of Galaxy Bulges
TL;DR: In this paper, the authors discuss the main developments and results in the quest to better understand the 3D shape of galaxy bulges and present the current view on the Milky Way bulge and future prospects in the field.
Journal ArticleDOI
Evidence for non-axisymmetry in M31 from wide-field kinematics of stars and gas
TL;DR: In this article, the authors derived stellar line-of-sight velocity distributions from the stellar absorption lines, as well as velocity distributions and line fluxes of the emission lines H$\beta$ and [NI] and obtained approximately 220 separate fields with the optical IFU spectrograph VIRUS-W.
References
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