Related papers: Two massive star-forming regions at early evolutio…

To understand evolutionary and environmental effects during the formation of high-mass stars, we observed three regions of massive star formation at different evolutionary stages that reside in the same natal molecular cloud. Methods. The…

We have observed the central region of the IR-dark cloud filament associated with IRAS 18507+0121 at millimeter wavelengths in CO(1-0), 13CO(1-0), and C18O(1-0) line emission and with the Spitzer Space Telescope at mid-IR wavelengths. Five…

We use SCUBA 850 micron and CO observations to analyze the surroundings of three Galactic ring-like HII regions, KR 7, KR 81, and KR 120 (Sh 2-124, Sh 2-165 and Sh 2-187), with the aim of finding sites of triggered star formation. We find…

We present observations of continuum (lambda = 0.7, 1.3, 3.6 and 18 cm) and OH maser (lambda = 18 cm) emission toward the young planetary nebula IRAS 17347-3139, which is one of the three planetary nebulae that are known to harbor water…

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…

In this article, we report high-resolution (~ 0.1" -- 0.3"), high-sensitivity (~ 50 -100 uJy beam-1) Very Large Array 0.7 and 1.3 cm observations of the young stellar system IRAS 16293-2422 in rho-Ophiuchus. In the 0.7 cm image, component A…

During star formation, the dense gas undergoes significant chemical evolution leading to the emergence of a rich variety of molecules associated with hot cores and hot corinos. The physical and chemical conditions are poorly constrained;…

Broadband spectroscopic observations with high sensitivity provide an unbiased way to detect emissions of molecules in space. We present deep observations from ~ 105.8 GHz to 113.6 GHz toward 50 Galactic massive star-forming regions using…

We present new near-IR H2, CO J=2-1, and CO J = 3-2 observations to study outflows in the massive star forming region IRAS 05358+3543. The Canada-France-Hawaii Telescope H2 images and James Clerk Maxwell Telescope CO data cubes of the IRAS…

We report the discovery of a young massive stellar cluster embedded in an extended HII region, invisible at optical wavelengths where the extinction is $A_V \approx 28$ magnitudes, associated with the IRAS source 16177-5018. $J, H$ and…

We present 7mm Very Large Array continuum images of the starburst galaxy M82. On arcsecond scales, two-thirds of the 7mm continuum consists of free-free emission from HII regions. In the subarcsecond resolution map, we identify 14 compact…

G0.253+0.016 is a remarkable massive infrared dark cloud located within $\sim$100 pc of the galactic center. With a high mass of $1.3 \times 10^5 M_\odot$, a compact average radius of $\sim$2.8 pc and a low dust temperature of 23 K, it has…

We present high-frequency (18-24 GHz) radio continuum observations towards 335 methanol masers, excellent signposts for young, embedded high-mass protostars. These complete the search for hypercompact HII (HCHII) regions towards young…

We present a multiwavelength study of five methanol maser sites which are not directly associated with a strong ($>100$ mJy) radio continuum source: G 31.28+0.06, G 59.78+0.06, G 173.49+2.42 (S231, S233IR), G 188.95+0.89 (S252, AFGL5180)…

The formation process of high-mass stars (>8M$_\odot$) is poorly constrained, particularly, the effects of clump fragmentation creating multiple systems and the mechanism of mass accretion onto the cores. We study the fragmentation of dense…

A fundamental question about the early evolution of low-mass protostars is when circumstellar disks may form. High angular resolution observations of molecular transitions in the (sub)millimeter wavelength windows make it possible to…

We have identified 453 compact dense cores in 3 mm continuum emission maps in the ATOMS (ALMA Three-millimeter Observations of Massive Star-forming regions) survey, and compiled three catalogues of high-mass star forming cores. One…

We report new results based on the analysis of the SMA and CARMA observations of NGC 7538\,IRS\,1 at 1.3 and 3.4 mm with sub-arcsec resolutions. With angular resolutions $\sim$ 0\farcs7, the SMA and CARMA observations show that the…

At the onset of high-mass star formation, accreting protostars are deeply embedded in massive cores made of gas and dust. Their spectral energy distribution is still dominated by the cold dust and rises steeply from near-to far-infrared…

To better understand the initial conditions of the high-mass star formation process, it is crucial to study at high-angular resolution the morphology, the kinematics, and eventually the interactions of the coldest condensations associated…