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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Large-scale Hydrodynamical Shocks as the Smoking-gun Evidence for a Bar in M31
TL;DR: In this paper , the authors identify sharp velocity jump features with a typical amplitude over 100 km s−1 in the central region of M31 (4.6 kpc × 2.3 kpc, or 20′×10′ ).
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The Complex Structure of the Bulge of M31
TL;DR: In this paper , the authors constructed models for the luminosity distribution of the bulge of M31 using the UVIT data and the galaxy image fitting algorithm GALFIT.
Book ChapterDOI
Molecular Gas in Spiral Galaxies
TL;DR: In this article, the authors highlight a number of recent surveys of molecular gas in nearby spiral galaxies and highlight the contributions of the recent BIMA Survey of Nearby Galaxies (SONG).
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