Related papers: Free-Floating HI Clouds in the M 81 Group
The Local Group offers an excellent laboratory for near-field cosmology by permitting us to use the resolved stellar content of its constituent galaxies as probes of galaxy formation and evolution, which in turn is an important means for…
Previous searches for atomic gas in our Galaxy's dwarf spheroidal companions have not been complete enough to settle the question of whether or not these galaxies have HI, especially in their outer parts. We present new observations of the…
The HI mass function (HIMF) for galaxies in the local universe is constructed from the results of the Arecibo HI Strip Survey, a blind extragalactic survey in the 21cm line. The survey consists of two strips covering in total 65 square…
We present an analysis of the properties of HI holes detected in 20 galaxies that are part of "The HI Nearby Galaxy Survey" (THINGS). We detected more than 1000 holes in total in the sampled galaxies. Where they can be measured, their sizes…
We report the results of a survey of the region within 40 arcmin of NGC 891, a nearby nearly perfectly edge-on spiral galaxy. Candidate "non-stars" with diameters greater than 15 arcsec were selected from the GSC 2.3.2 catalog and…
Dwarf satellite galaxies are a key probe of dark matter and of galaxy formation on small scales and of the dark matter halo masses of their central galaxies. They have very low surface brightness, which makes it difficult to identify and…
We have commenced a 21-cm survey of the entire southern sky (\delta < 0 degrees, -1200 km/s < v < 12700 km/s) which is ''blind'', i.e. unbiased by previous optical information. In the present paper we report on the results of a pilot…
Dwarf spheroidal galaxies (dSphs) have been extensively investigated in the Local Group, but their low luminosity and surface brightness make similar work in more distant galaxy groups challenging. Modern instrumentation unlocks the…
A survey of 329 nearby galaxies (redshift z < 0.045) has been conducted to study the distribution of mass and light within spiral galaxies over a range of environments. The 18 observed clusters and groups span a range of richness, density,…
We present observations of the HI tidal arm near dwarf galaxy NGC 3077 (member of the M81 galaxy group) in narrow band [SII] and H_alpha filters. Observations were carried out in March 2011 with the 2m RCC telescope at NAO Rozhen, Bulgaria.…
Sensitive 21cm HI observations have been made with the Green Bank Telescope toward the newly-discovered Local Group dwarf galaxy Hydra II, which may lie within the leading arm of the Magellanic Stream. No neutral hydrogen was detected. Our…
A number of mechanisms have been proposed to connect star-forming dwarf irregular galaxies with the formation of non-star-forming dwarf spheroidal galaxies, but distinguishing between these mechanisms has been difficult. We use the Via…
We provide new post-COSTAR data on one sightline (Mrk 421) and updated data from another (I Zw 1) from our Hubble Space Telescope (HST) survey of intergalactic Lyman-alpha clouds located along sightlines to four bright quasars passing…
We present new multi-wavelength scaling relations between the neutral hydrogen content (HI) and the stellar properties of nearby galaxies selected from the HI Parkes All-Sky Survey (HIPASS). We use these new scaling relations to investigate…
We have obtained deep Hubble Space Telescope (HST) imaging of 19 dwarf galaxy candidates in the vicinity of M101. Advanced Camera for Surveys HST photometry for 2 of these objects showed resolved stellar populations and Tip of the Red Giant…
Neutral hydrogen VLA D-array observations of the dwarf irregular galaxy HoII, a prototype galaxy for studies of shell formation, are presented. HI is detected to radii over 16' or 4 R_25, and M_HI=6.44x10^8 M_sun. The total HI map has a…
We present the analysis of the diffuse, low column density HI environment of 18 MHONGOOSE galaxies. We obtained deep observations with the Robert C. Byrd Green Bank Telescope, and reached down to a 3sigma column density detection limit of…
Long-slit observations of 4 dwarf spheroidal galaxies in the M81 group are presented. We have obtained a heliocentric velocity of globular cluster candidate located near the center of DDO78 to be +55 +- 10 km/s by cross-correlation with…
The fine details of the large-scale structure in the local universe provide important empirical benchmarks for testing cosmological models of structure formation. Dwarf galaxies are key object for such studies. Enlarge the sample of known…
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…