Bibcode
Pignatelli, E.; Corsini, E. M.; Vega Beltrán, J. C.; Scarlata, C.; Pizzella, A.; Funes, J. G.; Zeilinger, W. W.; Beckman, J. E.; Bertola, F.
Referencia bibliográfica
Monthly Notices of the Royal Astronomical Society, Volume 323, Issue 1, pp. 188-210.
Fecha de publicación:
5
2001
Número de citas
29
Número de citas referidas
26
Descripción
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|<~8arcsec) 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.