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We present the ionized-gas kinematics and photometry of a sample of 4 spiral galaxies which are characterized by a zero-velocity plateau along the major axis and a velocity gradient along the minor axis, respectively. By combining these new kinematical data with those available in the literature for the ionized-gas component of the S0s and spirals listed in the Revised Shapley-Ames Catalog of Bright Galaxies we realized that about 50% of unbarred galaxies show a remarkable gas velocity gradient along the optical minor axis. This fraction rises to about 60% if we include unbarred galaxies with an irregular velocity profile along the minor axis. This phenomenon is observed all along the Hubble sequence of disk galaxies, and it is particularly frequent in early-type spirals. Since minor-axis velocity gradients are unexpected if the gas is moving onto circular orbits in a disk coplanar to the stellar one, we conclude that non-circular and off-plane gas motions are not rare in the inner regions of disk galaxies.
(Abridged) Spiral galaxies often have extended outflows that permeate beyond the region of the disk. Such outflows have been seen both in starburst galaxies, actively star forming galaxies and galaxies with an AGN. In the latter galaxies it is unknow
We present minor axis kinematic profiles for a well-studied sample of 19 early- to intermediate-type disk galaxies. We introduce, for the first time, the use of single-burst stellar population (SSP) models to obtain stellar velocities, velocity dispe
The relationship between abundances and orbital parameters for 235 F- and G-type intermediate- and low- mass stars in the Galaxy is analyzed. We found that there are abundance gradients in the thin disk in both radial and vertical directions (-0.116
We present absorption-line index gradients for a sample of S0 galaxies in the Fornax Cluster. The sample has been selected to span a wide range in galaxy mass, and the deep VLT-FORS2 spectroscopy allows us to explore the stellar populations all the w
The M82 `cap is a gas cloud at a projected radius of 11.6 kpc along the minor axis of this well known superwind source. The cap has been detected in optical line emission and X-ray emission and therefore provides an important probe of the wind energe