Related papers: HI ``Tails'' from Cometary Globules in IC1396
We report the discovery of two kinematically anomalous atomic hydrogen (HI) clouds in M 100 (NGC 4321), which was observed as part of the Deciphering the Interplay between the Interstellar medium, Stars, and the Circumgalactic medium…
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…
There is mounting evidence for an extra-planar gas layer around the Milky Way disk, similar to the anomalous HI gas detected in a few other galaxies. As much as 10% of the gas may be in this phase. We analyze HI clouds located in the…
The DR 21 massive star forming region contains two cometary HII regions, aligned nearly perpendicular to each other on the sky. This offers a unique opportunity to discriminate among models of cometary HII regions. We present hydrogen…
As part of an effort to enlarge the number of well-studied Magellanic-type galaxies, we obtained broadband optical imaging and neutral hydrogen radio synthesis observations of the dwarf irregular galaxy ESO 364-G 029. The optical morphology…
We investigate the ionized gas kinematics of HII regions in the disk of NGC 7331 using integral field unit data collected with the Circumgalactic H$\alpha$ Spectrograph (CH$\alpha$S). NGC 7331 is a well-studied nearby galaxy with HII…
We present a new high-sensitivity HI observation toward nearby spiral galaxy M101 and its adjacent 2$^{\circ}\times$ 2$^{\circ}$ region using the Five-hundred-meter Aperture Spherical radio Telescope (FAST). From the observation, we detect…
Using the Optimal Filter Technique applied to Sloan Digital Sky Survey photometry, we have found extended tails stretching about 1 degree (or several tens of half-light radii) from either side of the ultra-faint globular cluster Palomar 1.…
The concordance model of cosmology and structure formation predicts the formation of isolated very massive stars at high redshifts in dark matter dominated halos of 10^5 to 10^6 Msun. These stars photo-ionize their host primordial molecular…
C18O spectral line observations, NIR spectrosopy, narrow and broad band NIR imaging and stellar J,H,Ks photometry are used to analyse the structure of the archetype cometary globule 1 (CG 1) head and the extinction of stars in its…
A new mechanism for the formation of cometary tails behind dense clouds or globules is discussed. Numerical hydrodynamical models show that when a dense shell of swept-up matter overruns a cloud, material in the shell is focussed behind the…
We analyze line-of-sight atomic hydrogen (HI) line profiles of 31 nearby, low-mass galaxies selected from the Very Large Array - ACS Nearby Galaxy Survey Treasury (VLA-ANGST) and The HI Nearby Galaxy Survey (THINGS) to trace regions…
Given the rarity of young O star candidates, compact HII regions embedded in dense molecular cores continue to serve as potential sites to peer into the details of high-mass star formation. To uncover the ionizing sources of the most…
We present preliminary results from the Southern Galactic Plane Survey (SGPS) Test Region and Parkes data. As part of the pilot project for the Southern Galactic Plane Survey, observations of a Test Region (325.5 deg < l < 333.5 deg; -0.5…
The study of hyper-compact (HC) or ultra-compact (UC) HII regions is fundamental to understanding the process of massive (> 8 M_sun) star formation. We employed Atacama Large Millimeter/submillimeter Array (ALMA) 1.4 mm Cycle 6 observations…
We report the discovery of tidal tails around the high-latitude Galactic globular cluster NGC 5466 in Sloan Digital Sky Survey (SDSS) data. Neural networks are used to reconstruct the probability distribution of cluster stars in u,g,r,i and…
Observing giant HII regions at fine spatial scales uncovers detailed structures and reveals variations in ionization, abundance, and dynamical properties of ionized gas and the effect of stellar feedback. Using emission line data of M33…
We report the first evidence of a hot corino in a Bok globule. This is based on the ALMA observations in the 1.2 mm band toward the low-mass Class 0 protostar IRAS 19347+0727 in B335. Saturated complex organic molecules (COMs), CH$_3$CHO,…
We briefly summarize the survey of HI 21 cm emission lines to search for shocked atomic gas associated with Galactic supernova remnants (SNRs) in the southern sky. For G347.3-0.5, we discuss the distance to the SNR and the implications of…
We present the first results of an ongoing project to investigate the present-day chemical abundances of the extreme outer parts of galactic disks, as probed by the emission line spectra of a new sample of HII regions. The galaxies studied…