Related papers: The vertical structure and kinematics of HI in spi…
The results of observational studies on the vertical HI density distribution and kinematics of the disks of spiral galaxies are reported and discussed. Attention is drawn to the presence of HI emission, unknown before and here referred to…
We discuss new, high sensitivity HI observations of the spiral galaxy NGC2403 which show extended emission at anomalous velocities with respect to the `cold' disk. This `anomalous' gas component (~1/10 of the total HI mass) is probably…
The neutral hydrogen line profiles along the major axis of the nearby spiral galaxy NGC 2403 show a wing towards the sytemic velocity. This asymmetry can be explained with the presence of an abnormally thick HI disk (FWHM ~ 5 kpc) or with a…
High sensitivity H I observations of the nearby spiral galaxy NGC 2403 obtained with the VLA are presented and discussed. The properties of the extended, differentially rotating H I layer with its H I holes, spiral structure and outer warp…
Recent, high sensitivity, HI observations of nearby spiral galaxies show that their thin `cold' disks are surrounded by thick layers (halos) of neutral gas with anomalous kinematics. We present results for three galaxies viewed at different…
We present a study of the kinematics of the ionised gas in the nearby spiral galaxy NGC 2403 using deep long-slit spectra obtained with the 4.2-m William Herschel Telescope. The data show the presence of a halo component of ionised gas that…
A study is presented of HI line observations of the nearby spiral galaxy NGC 3521 observed with the VLA as part of The HI Nearby Galaxy Survey. Clearly evident in the HI data cube is the presence of an anomalous HI component that is both…
We have analyzed high velocity resolution HI synthesis observations of the nearly face-on Sc galaxy NGC 1232. The neutral gas distribution extends well beyond the optical extent of the galaxy. As expected, local peaks in the HI column…
VLA and Parkes 64 m radiotelescope 21-cm observations of the starburst dwarf galaxy NGC 5253 reveal a multi-component non-axisymmetric HI distribution. The component associated with the stellar body shows evidence for a small amount of…
Neutral hydrogen observations of the nearby, edge-on spiral galaxy NGC 891 reveal the presence of an HI halo extending up to at least 5 kpc from the plane. This halo gas appears to rotate 25 to 100 km/s more slowly than the gas in the…
Observations of the nearby starburst galaxy NGC 253 in the 21-cm line reveal the presence of neutral hydrogen in the halo, up to 12 kpc from the galactic plane. This extra-planar HI is found only in one half of the galaxy and is…
We present 21-cm observations and models of the HI kinematics and distribution of NGC 4244, a nearby edge-on Scd galaxy observed as part of the Westerbork Hydrogen Accretion in LOcal GAlaxieS (HALOGAS) survey. Our models give insight into…
Observations of the neutral atomic hydrogen (HI) in the nuclear starburst galaxy NGC 4945 with MeerKAT are presented. We find a large amount of halo gas, previously missed by HI observations, accounting for 6.8% of the total HI mass. This…
We have mapped the emission from atomic hydrogen at 21 cm from the galaxy NGC 3783 with the Australia Telescope Compact Array. Our main results are: a) the HI morphology is irregular and perturbed, gathered in three blobs apparently…
We study the neutral hydrogen distribution and kinematics in the Local Group dwarf irregular galaxy IC 1613 and compare them with the ionized gas distribution and stellar content of the galaxy. We discuss several mechanisms which may be…
We present a study of the distribution and kinematics of the neutral gas in the low-inclination Scd galaxy NGC 6946. The galaxy has been observed for 192 hours at 21-cm with the Westerbork Synthesis Radio Telescope. These are among the…
Deep VLA HI observations of the nearby spiral galaxy NGC 2403 reveal the presence of an extended HI halo that shows slower rotation and a general inflow (about 15-25 km\s) towards the center of the galaxy.
We present UBVJHKHalpha and HI data of the irregular galaxy NGC 2366. It is a normal boxy-shaped disk seen at high inclination angle. We do not see any unambiguous observational signature of a bar. There is an asymmetrical extension of…
We model the observed vertical distribution of the neutral hydrogen (HI) in the faint (M_B ~ -13.7 mag) edge-on dwarf irregular galaxy KK250. Our model assumes that the galaxy consists of axi-symmetric, co-planar gas and stellar discs in…
Spiral galaxies appear to be dynamical systems whose disks are still forming at the current epoch and which continue to accrete mass. The presence of extraplanar gas in spirals indicates that galactic halos can contain at least part of the…