Related papers: Dark Matter and HI in Ultra-Diffuse Galaxy UGC 216…
We present the results of HI observations of five groups of galaxies spanning a range of velocity dispersion and spiral fraction (brightest optical group member in parenthesis): NGC 7582 (NGC 7552), USGC U207 (NGC 2759), USGC U070 (NGC…
We present 21-cm HI line and 408 MHz and 1.4 GHz continuum observations of the dwarf galaxy UGCA 86 with the DRAO synthesis telescope. UGCA 86 is detected in the continuum at 408 MHz (S_{408} = 120 +/- 30 mJy) and 1.4 GHz (S_{1400} = 79 +/-…
NGC 2915 is a nearby blue compact dwarf with the HI properties of a late-type spiral. Its large, rotating HI disk (extending out to R ~ 22 B-band scale lengths) and apparent lack of stars in the outer HI disk make it a useful candidate for…
We use recent very extended HI kinematics (out to 48 kpc) along with previous H$\alpha$ kinematics of the spiral galaxy NGC 3198 in order to derive its distribution of dark matter (DM). First, we used a chi-square method to model the…
We analyse the detailed structure of a highly-inclined (i>~80 degrees) disc galaxy which lies within the Hubble Ultra Deep Field (UDF). The unprecedented depth of the UDF data allow disc and extraplanar emission to be reliably traced to…
Many ultra diffuse galaxies (UDGs) have now been identified in clusters of galaxies. However, the number of nearby UDGs suitable for detailed follow-up remain rare. Our aim is to begin to identify UDGs in the environments of nearby bright…
We have used the VLA to image the HI 21-cm line emission in the edge-on Sd galaxy IC2233 and the blue compact dwarf NGC2537. We also present new optical B,R, and H alpha imaging of IC2233 obtained with the WIYN telescope. Despite evidence…
We present VLA H I observations of the low surface brightness galaxy UGC 12695 and its two companions, UGC 12687 and a newly discovered dwarf galaxy 2333+1234. UGC 12695 shows solid body rotation but has a very lopsided morphology of the H…
Based on a new HI survey using the Five-hundred-meter Aperture Spherical radio Telescope (FAST), combined with the Pan-STARRS1 images, we identified an isolated HI cloud without any optical counterpart, named FAST J0139+4328. The newly…
There is a growing consensus that the vast majority of ultra-diffuse galaxies (UDGs) are dwarf galaxies. However, there remain a few UDGs that seem to be special in terms of their globular cluster (GC) systems. In particular, according to…
Australia Telescope Compact Array HI-line observations of the nearby dwarf galaxy NGC 1705 are presented. The data are used to trace the gravitational potential of the galaxy out to several stellar disc scale lengths. A rotation curve is…
Recent observations have highlighted a significant population of faint but large (r_eff>1.5 kpc) galaxies in the Coma cluster. The origin of these Ultra Diffuse Galaxies (UDGs) remains puzzling, as the interpretation of the observational…
We report the discovery of diffuse ultraviolet light around late-type galaxies out to 5-20 kpc from the midplane using Swift and GALEX images. The emission is consistent with the stellar outskirts in the early-type galaxies but not in the…
We present spatially-resolved stellar kinematics of the well-studied ultra diffuse galaxy (UDG) Dragonfly 44, as determined from 25.3 hrs of observations with the Keck Cosmic Web Imager. The luminosity-weighted dispersion within the…
To date, there has been significant interest in globular cluster (GC)-rich ultra-diffuse galaxies (UDGs) and the evidence that they have formed via an unexpected, ``failed galaxy'' formation pathway. The majority of the evidence for…
We theoretically study the vertical structure of the edge-on low surface brightness (LSB) galaxy UGC 7321. This is one of the few well-observed LSBs. We modeled it as a gravitationally coupled disk system of stars and atomic hydrogen gas in…
We provide evidence that UGC1382, long believed to be a passive elliptical galaxy, is actually a giant low surface brightness (GLSB) galaxy which rivals the archetypical GLSB Malin 1 in size. Like other GLSB galaxies, it has two components:…
We present new multi-configuration HI aperture synthesis imaging of the nearby dwarf starburst galaxy NGC 625 obtained with the Australia Telescope Compact Array. Total HI column density images show gas well-aligned with the optical major…
VLA neutral hydrogen observations of the shell elliptical NGC 3656 reveal an edge-on, warped minor axis gaseous disk (M_HI ~ 2.10^9 Msun) extending 7 kpc. HI is also found outside the optical image, on two complexes to the North-East and…
We present new, high sensitivity VLA observations of HI in four dwarf galaxies (UGCA 292, GR8, DDO 210, and DDO 216) and we use these data to study interactions between star formation and the interstellar medium. HI velocity dispersions and…