Galaxy formation and evolution

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The FIR/submm window on galaxy formation

(1999)

Authors:

B Guiderdoni, FR Bouchet, J Devriendt, E Hivon, JL Puget

Kinematical signatures of hidden stellar discs

(1999)

Rates of tidal disruption of stars by massive central black holes

(1999)

Authors:

John Magorrian, Scott Tremaine

Central UV Spikes in two Galactic Spheroids

(1999)

Authors:

Michele Cappellari, Francesco Bertola, David Burstein, Lucio M Buson, Laura Greggio, Alvio Renzini

Kinematical signatures of hidden stellar discs

Monthly Notices of the Royal Astronomical Society 302:3 (1999) 530-536

Abstract:

The deprojection of the surface brightness distribution of an axisymmetric galaxy does not have a unique solution unless the galaxy is viewed precisely edge-on. I present an algorithm that finds the full range of smooth axisymmetric density distributions consistent with a given surface brightness distribution and inclination angle, and use it to investigate the effects of this non-uniqueness on the line-of-sight velocity profiles (VPs) of two-integral models of both real and toy discy galaxies viewed at a range of inclination angles. Photometrically invisible face-on discs leave very clear signatures in the minor-axis VPs of the models (Gauss-Hermite coefficients h4 ≳ 0.1), provided the disc-to-bulge ratio is greater than about 3 per cent. I discuss the implications of these hitherto neglected discs for dynamical modelling.