Related papers: Profiling Young Massive Stars
We present 1.4-mm BIMA observations with subarcsecond resolution of the bright dust and molecular line emission from hot cores associated with a sample of four ultracompact HII regions: G9.62+0.19, G10.47-0.03, G29.96-0.02, G31.41+0.31.…
The aim of this study is to investigate systematic chemical differentiation of molecules in regions of high mass star formation. We observed five prominent sites of high mass star formation in HCN, HNC, HCO+, their isotopes, C18O, C34S and…
Massive star formation exhibits an extremely rich chemistry. However, not much evolutionary details are known yet, especially at high spatial resolution. Therefore, we synthesize previously published Submillimeter Array…
6.7 GHz methanol masers are the brightest of class II methanol masers that are regarded as excellent signposts in the formation of young massive stars. We present here a molecular line study of 68 6.7 GHz methanol maser hosts chosen from…
Methanol masers at 6.7 GHz are known to be tracers of high-mass star formation in our Galaxy. In this paper, we study the large scale physical conditions in the star forming clumps/cores associated with 6.7 GHz methanol masers using…
We use sub-arcsecond resolution ($\sim$0.4$''$) observations with NOEMA at 1.37 mm to study the dust emission and molecular gas of 18 high-mass star-forming regions. We combine the derived physical and chemical properties of individual…
Context: We investigated the molecular gas associated with 6.7 GHz methanol masers throughout the Galaxy using a J=1-0 transition of the CO isotopologues. Methods:Using the 13.7-meter telescope at the Purple Mountain Observatory (PMO), we…
Based on color-selected IRAS point sources, we have started to conduct a survey of 47 high-mass star-forming regions in the southern hemisphere in 870um dust continuum and molecular line emission in several frequency ranges between 290 GHz…
To investigate whether distinctions exist between low and high-luminosity Class II 6.7-GHz methanol masers, we have undertaken multi-line mapping observations of various molecular lines, including the NH3(1,1), (2,2), (3,3), (4,4) and…
Pre-stellar cores represent a critical evolutionary phase in low-mass star formation. We aim to unveil the detailed thermal structure and density distribution of three early-stage cores, starless core L1517B, and prestellar core L694-2 and…
We report the results of subparsec-scale submillimeter observations towards an embedded high-mass young stellar object in the Small Magellanic Cloud (SMC) with ALMA. Complementary infrared data obtained with the AKARI satellite and the…
We present a multiwavelength study of five methanol maser sites which are not directly associated with a strong ($>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)…
We aim at characterising dense cores in the clustered environments associated with massive star-forming regions. For this, we present an uniform analysis of VLA NH3(1,1) and (2,2) observations towards a sample of 15 massive star-forming…
Among the tracers of the earliest phases in the massive star formation process, methanol masers have gained increasing importance. The phenomenological distinction between Class I and II methanol masers is based on their spatial association…
Methanol masers can provide valuable insight into the processes involved in high-mass star formation, however the local environment in which they form is still unclear. Four primary, yet conflicting, models have emerged to explain the…
We present a study of molecular outflows using high-resolution mapping of the CO (1-0) line emission toward eight relatively nearby 6.7 GHz methanol masers, which are associated with massive star forming regions. Outflows were detected in…
We report detection of moderate to high-mass star formation in an infrared dark cloud (G11.11-0.12) where we discovered class II methanol and water maser emissions at 6.7 GHz and 22.2 GHz, respectively. We also observed the object in…
Due to their wide wavelength coverage across the millimetre to centimetre (mm - cm) range and their increased sensitivity, modern interferometric arrays facilitate observations of the thermal and non-thermal emission from different stellar…
Molecular line observations of starless (prestellar) cores combined with a chemical evolution modeling and radiative transfer calculations are a powerful tool to study the earliest stages of star formation. However, conclusions drawn from…
Our mid-infrared and near-infrared surveys over the last five years have helped to strengthen and clarify the relationships between water, methanol, and OH masers and the star formation process. Our surveys show that maser emission seems to…