Modelling gaseous and stellar kinematics in the disc galaxies NGC 772, 3898 and 7782
- Author(s)
- Ezio Pignatelli, Enrico Maria Corsini, Juan Carlos Vega Beltran, C Scarlata, Alessandro Pizzella, Jose Gabriel Funes, Werner Zeilinger, John E. Beckman, Francesco Bertola
- Abstract
We present V-band surface photometry and major-axis kinematics of stars and ionized gas of three early-type spiral galaxies, namely NGC 772, 3898 and 7782. For each galaxy we present a self-consistent Jeans model for the stellar kinematics, adopting the light distribution of bulge and disc derived by means of a two-dimensional parametric photometric decomposition. This allows us to investigate the presence of non-circular gas motions, and derive the mass distribution of luminous and dark matter in these objects. NGC 772 and 7782 have apparently normal kinematics with the ionized gas tracing the gravitational equilibrium circular speed. This is not true in the innermost region (|r| ? 8 arcsec) of NGC 3898, where the ionized gas is rotating more slowly than the circular velocity predicted by dynamical modelling. This phenomenon is common in the bulge-dominated galaxies for which dynamical modelling enables us to make the direct comparison between the gas velocity and the circular speed, and it poses questions about the reliability of galaxy mass distributions derived by the direct decomposition of the observed ionized-gas rotation curve into the contributions of luminous and dark matter.
- Organisation(s)
- Department of Astrophysics
- External organisation(s)
- Osservatorio Astronomico, University of Padova, Institute of Astrophysics of the Canary Islands, Vatican Observatory
- Journal
- Monthly Notices of the Royal Astronomical Society
- Volume
- 323
- Pages
- 188-210
- No. of pages
- 23
- ISSN
- 0035-8711
- Publication date
- 2001
- Peer reviewed
- Yes
- Austrian Fields of Science 2012
- 103003 Astronomy
- Portal url
- https://ucrisportal.univie.ac.at/en/publications/modelling-gaseous-and-stellar-kinematics-in-the-disc-galaxies-ngc-772-3898-and-7782(ccaeebc1-368d-4589-b63e-bac492af8e58).html