Related papers: A Bigger Cloud 9? New HI Observations of the RELHI…
For the GMRT, we calculate the expected signal from redshifted HI emission at two frequency bands centered at 610 and 325 MHz. The study focuses on the visibility-visibility cross-correlations, proposed earlier as the optimal statistical…
We present a 21cm line HI self-absorption (HISA) survey of cold atomic gas within Galactic longitudes 75 to 146 degrees and latitudes -3 to +5 degrees. We identify HISA as spatially and spectrally confined dark HI features and extract it…
A bright feature 80 pc away from the core in the powerful jet of M87 shows highly unusual properties. Earlier radio, optical and X-ray observations have shown that this feature, labeled HST-1, is superluminal, and is possibly connected with…
We present an analysis comparing the properties of 45 giant molecular clouds (GMCs) in M33 and the atomic hydrogen (HI) with which they are associated. High-resolution VLA observations are used to measure the properties of HI in the…
We use a large N-body simulation to examine the detectability of HI in emission at redshift z ~ 1, and the constraints imposed by current observations on the neutral hydrogen mass function of galaxies at this epoch. We consider three…
The Canadian Large Adaptive Reflector (CLAR) is a proposed prototype of a new concept for large, filled-aperture radio telescopes. The prototype would have a 300-metre aperture, working up to frequencies of at least 1.4 GHz, and would be…
We present HI observations of the edge-on galaxy NGC 891. These are among the deepest ever performed on an external galaxy. They reveal a huge gaseous halo, much more extended than seen previously and containing almost 30 % of the HI. This…
Five galaxy groups with properties similar to those of the Local Group have been surveyed for HI clouds with the Arecibo Telescope. In total 300 pointings have been observed on grids of approximately 2.5 x 1.5 Mpc centred on the groups. The…
Ultra-deep WFC3/IR observations on the HUDF from the HUDF09 program revealed just one plausible z~10 candidate UDFj-39546284. UDFj-39546284 had all the properties expected of a galaxy at z~10 showing (1) no detection in the deep ACS+WFC3…
The planetary nebula M94--20 in the Large Magellanic Cloud was serendipitously observed with the Space Telescope Imaging Spectrograph on board the Hubble Space Telescope as part of the Hubble Space Telescope Archival Pure Parallel Program.…
We present a comprehensive analysis of atomic hydrogen (HI) properties using a semi-analytical model of galaxy formation and N-body simulations covering a large cosmological volume at high resolution. We examine the HI mass function and the…
We present aperture synthesis imaging of dense molecular gas in the Large Magellanic Cloud, taken with the prototype millimeter receivers of the Australia Telescope Compact Array (ATCA). Our observations of the N113 HII region reveal a…
We present results on two related topics: 1. A discussion of high redshift candidates (z>4.5), and 2. A study of very small galaxies at intermediate redshifts, both sets being detected in the region of the northern Hubble Deep Field covered…
We have observed 11 compact high-velocity clouds in the 21-cm line of neutral hydrogen with the 100-m telescope in Effelsberg. Our observations show that most of the clouds have a rather complex morphology. Head-tail structures and…
The results of a spectroscopic survey of H alpha emission line stars associated with fourteen bright rimmed clouds are presented. Slit-less optical spectroscopy was carried out with the Inter University Centre for Astronomy and Astrophysics…
A sample of 279 massive red spirals was selected optically by Guo et al. (2020), among which 166 galaxies have been observed by the ALFALFA survey. In this work, we observe HI content of the rest 113 massive red spiral galaxies using the…
We present an improved determination of the Hubble constant (H0) from Hubble Space Telescope (HST) observations of 70 long-period Cepheids in the Large Magellanic Cloud. These were obtained with the same WFC3 photometric system used to…
We present the results from our search for HI 21-cm absorption in a sample of 16 strong FeII systems ($W_{\rm r}$(MgII $\lambda2796$) $\ge1.0$ \AA\ and $W_{\rm r}$(FeII $\lambda2600$) or $W_{\rm FeII}$ $\ge1$ \AA) at $0.5<z<1.5$ using the…
A 25 $\rm deg^2$ region, including the M81 complex (M81, M82, NGC 3077), NGC 2976 and IC2574, was mapped during ~3000 hours with the DRAO synthesis telescope. With a physical resolution of ~1 kpc, these observations allow us to probe a…
Hypercompact HII regions (HC) are regions of ionized gas associated with the early stages of high-mass star formation. With the aim of better understanding their characteristics, we studied five candidate HC HII regions. Here, we present…