Related papers: Triggered star formation in a molecular shell crea…

We report on EVN imaging of the 6.7 GHz methanol maser emission from the candidate high-mass protostar G23.657-0.127. The masers originate in a nearly circular ring of 127 mas radius and 12 mas width. The ring structure points at a central…

RX J0046.5$-$7308 is a shell-type supernova remnant (SNR) in the Small Magellanic Cloud (SMC). We carried out new $^{12}$CO($J$ = 1-0, 3-2) observations toward the SNR using Mopra and the Atacama Submillimeter Telescope Experiment. We found…

We present molecular spectroscopy toward 50 Galactic supernova remnants (SNRs) taken at millimeter wavelengths in 12CO and 13CO J=2-1 with the Heinrich Hertz Submillimeter Telescope as part of a systematic survey for broad molecular line…

M17 is one of the youngest and most massive nearby star-formation regions in the Galaxy. It features a bright H II region erupting as a blister from the side of a giant molecular cloud (GMC). Combining photometry from the Spitzer GLIMPSE…

We report discovery of a shell like structure G354.4+0.0 of size 1.6' that shows morphology of a shell supernova remnant. Part of the structure show polarized emission in NRAO VLA sky survey (NVSS) map. Based on 330 MHz, 1.4 GHz Giant…

We report the discovery of a dense molecular ring-like structure in a dense (10$^5$ cm$^{-3}$), cold (pc-scale CO depletion at a factor of 5), and young (10$^4$ year) star-forming region G34.74-0.12, revealed by C$^{18}$O (2-1), HNC (1-0),…

We have carried out 21 cm radio continuum, H76_\alpha radio recombination line, and various (CO, ^13CO, CS, & C^34S) molecular line observations of the W31 complex. Our radio continuum data show that W31 is composed of two extended HII…

G7.7$-$3.7 is a possible historical SNR, with the origin of its cocoon-like morphology and its supernova type remaining unclear. We performed L-band radio polarization observations of G7.7$-$3.7 using the Very Large Array in C and…

Young massive stars or clusters are often observed at the peripheries of HII regions. What triggers star formation at such locations? Among the scenarios that have been proposed, the `collect and collapse' process is particularly attractive…

It is often assumed that the strong gravitational field of a super-massive black hole disrupts an adjacent molecular cloud preventing classical star formation in the deep potential well of the black hole. Yet, young stars have been observed…

We present high angular resolution Submillimeter Array (SMA) and Karl G. Jansky Very Large Array (VLA) observations of the massive protocluster G18.67+0.03. Previously targeted in maser surveys of GLIMPSE Extended Green Objects (EGOs), this…

G18.93-0.03 is a prominent dust complex within an 0.8deg long filament, with the molecular clump G18.93/m being IR dark from near IR wavelength up to 160mu. Spitzer composite images show an IR bubble spatially associated with G18.93. We use…

The nature of the mechanism responsible for producing the spectacular, geometrically thin, spherical shells found around some carbon stars has been an enigma for some time. Based on extensive radiative transfer modelling of both CO line…

We report the results of molecular line observations toward the l=1.3 deg complex, ananomalous cloud complex in the central molecular zone of the Galaxy. We have taken high resolution maps of the CO J=1-0, HCN J=1-0, HCO+ J=1-0, SiO J=1-0…

We examine the recent star formation associated with four supergiant shells (SGSs) in the Large Magellanic Cloud (LMC): LMC 1, 4, 5, and 6, which have been shown to have simple expanding-shell structures. H II regions and OB associations…

We present the discovery of expanding spherical shells around low to intermediate-mass young stars in the Orion A giant molecular cloud using observations of $^{12}$CO (1-0) and $^{13}$CO (1-0) from the Nobeyama Radio Observatory 45-meter…

Through observations and modeling, we demonstrate how the recently discovered large-scale bar in NGC 5248 generates spiral structure which extends from 10 kpc down to 100 pc, fuels star formation on progressively smaller scales, and drives…

Using a specialized technique sensitive to the presence of expanding ionized gas we have detected a set of three concentric expanding shells in an HII region in the nearby spiral galaxy M33. After mapping the kinematics in H{\alpha} with…

We present a study of active stellar forming regions in the environs of the HII region Sh2-205. The analysis is based on data obtained from point source catalogues and images extracted from 2MASS, MSX, and IRAS surveys. Complementary data…

Recent ASCA observations of G347.3-0.5, an SNR discovered in the ROSAT All-Sky Survey, reveal nonthermal emission from a region along the northwestern shell (Koyama et al. 1997). Here we report on new pointed ASCA observations of G347.3-.5…