Astronomy and Astrophysics, volume 307, 391-402 (1996/3-2)
Extended ionized gas in elliptical galaxies. I. Multicomponents in NGC 1052 and NGC 7332.
PLANA H. and BOULESTEIX J.
Abstract (from CDS):
A number of elliptical galaxies possess an extended gaseous disk usually detected in [OIII]5007A, Hα or [NII]6583A emission lines. 3-D scanning Perot-Fabry observations of two of these objects, NGC 1052 and NGC 7332, show multiple profiles of the ionized faint and extended gas. We separate clearly two extended gaseous components in both galaxies where gas kinematics is largely decoupled from stellar one. Several gas systems, kinematically decoupled and possibly located in different basic planes of the ellipsoids, could be related to different external origins. We used gas kinematics to constraint the triaxial shape of these galaxies. Both present a typical gaseous disk which may lie in an allowed preferred plane of the ellipsoid. But there is no clear coherence between dynamical parameters derived separately from the gaseous disks. Different hypothesis, in which one component is not definitively stable, are presented. They suppose that successive mergers occurred within a relatively small time scale.
galaxies: elliptical and lenticular - kinematics and dynamics: individual: NGC 1052, NGC 7332