The distribution of ionized gas in early-type galaxies III. M/L determinations based on triaxial models

Author(s)
Alessandro Pizzella, P Amico, Francesco Bertola, Lucio M Buson, I. John Danziger, Herwig B. Dejonghe, Elaine M Sadler, Roberto P Saglia, P Tim de Zeeuw, Werner Zeilinger
Abstract

The velocity fields of ionized gas disks in four elliptical galaxies have been exploited to derive the mass-to-light ratios as function of radial distance. For each galaxy, namely NGC 1453, NGC 2974, NGC 5077 and NGC 7097, we derive a set of intrinsic shapes of the stellar component and viewing angles that are consistent with the observed ellipticities and orientation of the isophotes. A least-squares fit to the observed velocity field gives the set of parameters defining the potential that best reproduces the kinematics of the ionized gas disk as well as the mass density and light density radial profiles. For three galaxies a satisfactory model is found. The M/L ratio does change within individual galaxies, though not showing any systematic increase with radius and has a mean value of about 5M?/LB ?out to ~ 1Re.

Organisation(s)
Department of Astrophysics
External organisation(s)
University of Padova, European Southern Observatory (Germany), Osservatorio Astronomico, INAF Osservatorio Astronomico di Palermo, Ghent University , The University of Sydney, Max-Planck-Institut für extraterrestrische Physik, Leiden University
Journal
Astronomy & Astrophysics
Volume
323
Pages
349-356
No. of pages
8
ISSN
0004-6361
Publication date
1997
Peer reviewed
Yes
Austrian Fields of Science 2012
103003 Astronomy
Portal url
https://ucris.univie.ac.at/portal/en/publications/the-distribution-of-ionized-gas-in-earlytype-galaxies-iii-ml-determinations-based-on-triaxial-models(ed18e4a3-5542-4cf9-a2ad-bd4e1e2c2e16).html