Related papers: Study of Molecular Clouds associated with HII Regi…
The accepted explanation of the observed dichotomy of two orders of magnitude between in situ measurements of electron density in HII regions, derived from emission line ratios, and average measurements based on integrated emission measure,…
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…
Massive clumps within the swept-up shells of bubbles, like that surrounding the galactic HII region RCW 120, have been interpreted in terms of the Collect and Collapse (C&C) mechanism for triggered star formation. The cold, dusty clumps…
Massive stars are expected to produce wind-blown bubbles in the interstellar medium; however, ring nebulae, suggesting the existence of bubbles, are rarely seen around main-sequence O stars. To search for wind-blown bubbles around…
In order to understand the star formation process under the influence of HII regions, we have carried out extensive investigations to well selected star-forming regions which all have been profoundly affected by existing massive O type…
We review the progress that has been made in observing and analyzing molecular cloud structure in recent years. Structures are self-similar over a wide range of scales with similar power law indices independent of the star forming nature of…
Star-forming regions are usually studied in the context of Galactic surveys, but dedicated observations are sometimes needed when the study reaches beyond the survey area. Here, we studied the G345.5+1.5 region, which is located slightly…
We present an analysis of the region IRAS 08589-4714 with the aim of characterizing the molecular environment. We observed the CO(3-2), ^{13}CO(3-2), C^{18}O(3-2), HCO+(3-2), and HCN(3-2) molecular lines in a region of 150" x 150", centered…
As a part of the Milky Way Imaging Scroll Painting (MWISP) survey, we performed a simultaneous 12CO(1-0), 13CO(1-0), C18O(1-0) mapping toward molecular clouds in a region encompassing 3.75 square degrees. We reveal three molecular clouds,…
We present observations of HCO+ and H^13CO+, N2H+, HCS+, HCN and HN^13C, SO and ^34SO, CCH, SO_2, and CH_3OH-E towards a sample of 27 high-mass clumps coincident with water maser emission. All transitions are observed with or convolved to…
Young HII regions are an important site to study O star formation based on distributions of ionized and molecular gas. We revealed that two molecular clouds at $\sim 48$ km s$^{-1}$ and $\sim 53$ km s$^{-1}$ are associated with the HII…
We present a complete sample of molecular clumps containing compact and ultra-compact (UC) HII regions between \ell=10\degr and 60\degr\ and $|b|<1\degr, identified by combining the the ATLASGAL submm and CORNISH radio continuum surveys…
We studied star formation activities in the molecular clouds in the Large Magellanic Cloud. We have utilized the second catalog of 272 molecular clouds obtained by NANTEN to compare the cloud distribution with signatures of massive star…
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 observational constraints on the nature of the different core-collapse supernova types through an investigation of the association of their explosion sites with recent star formation, as traced by H-alpha +[NII] line emission. We…
To understand the formation process of massive stars, we present a multi-scale and multi-wavelength study of the W31 complex hosting two extended HII regions (i.e., G10.30-0.15 (hereafter, W31-N) and G10.15-0.34 (hereafter, W31-S)) powered…
To investigate the process of star formation triggered by the expansion of an HII region, we present a multi-wavelength analysis of the Galactic HII region RCW 120 and its surroundings. The collect and collapse model predicts that the layer…
We report the second complete molecular line data release from the {\em Census of High- and Medium-mass Protostars} (CHaMP), a large-scale, unbiased, uniform mapping survey at sub-parsec resolution, of mm-wave line emission from 303…
We present the results of 450 and 850 micron continuum mapping of the HII region KR 140 using the SCUBA instrument on the JCMT. KR 140 is a small (5.7 pc diameter) HII region at a distance of 2.3+/-0.3 kpc. Five of the six IRAS point…
Using 3D MHD simulation with the effects of radiative cooling/heating, chemical reactions, and thermal conduction, we investigate the formation of molecular cloud in the ISM. We consider the formation of molecular cloud by accretion of the…