Related papers: N2H+ and HC3N Observations of the Orion A Cloud
The three dimensional structure of the brightest part of the Orion Nebula is assessed in the light of published and new data. We find that the widely accepted model of a concave blister of ionized material needs to be altered in the…
Multiline observations of C18O and SiO isotopomers toward 33 molecular peaks in the Galactic center region, taken at the SEST, JCMT and HHT telescopes, are presented. The C18O presumably traces the total H_2 column density, while the SiO…
We report observations and an analysis of the distribution of HCO+(1-0) and HCO+(4-3) emission in the central 1 kpc star forming region of M82. Comparisons are made with other star formation indicators such as the mm continuum, the…
We have extended the work of Papers I and II of this series to determine at higher spatial resolution the properties of the embedded Orion-S Molecular Cloud that lies within the ionized cavity of the Orion Nebula and of the thin ionized…
Large scale mapping observations of the 3P1-3P0 fine structure transition of atomic carbon (CI, 492 GHz) and the J=3-2 transition of CO (346 GHz) toward the Orion A molecular cloud have been carried out with the Mt. Fuji submillimeter-wave…
We present a Nobeyama 45 m Radio Telescope map and Australia Telescope Compact Array pointed observations of N2H+ 1-0 emission towards the clustered, low mass star forming Oph B Core within the Ophiuchus molecular cloud. We compare these…
We present high-resolution ($\sim$1000 AU) 3 mm observations with the NOrthern Extended Millimeter Array toward the DR21 South Filament, aiming to reveal its internal fragmentation and search for deeply embedded star-forming activities.…
The Orion Molecular Complex is the nearest site of ongoing high-mass star formation, making it one of the most extensively studied molecular complexes in the Galaxy. We have developed a new technique for mapping the 3D distribution of dust…
We present new, wide and deep images in the 1.1 mm continuum and the $^{12}$CO ($J$=1-0) emission toward the northern part of the Orion A Giant Molecular Cloud (Orion-A GMC). The 1.1 mm data were taken with the AzTEC camera mounted on the…
We present further observational evidence in support of our earlier proposal (Houde et al. 2000) for detecting the presence of the magnetic field in molecular clouds by comparing spectra of molecular ions with those of neutral molecules.…
We have measured the deuterium fractionation (through the column density ratio N(N2D+)/N(N2H+)) and the CO depletion factor (ratio between expected and observed CO abundance) in a sample of 10 high-mass protostellar candidates, in order to…
In order to study a molecular-cloud-scale chemical composition, we have conducted a mapping spectral line survey toward the Galactic molecular cloud W3(OH), which is one of the most active star forming regions in the Perseus arm, with the…
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…
We derive the molecular properties for a sample of 301 Galactic HII regions including 123 ultra compact (UC), 105 compact, and 73 diffuse nebulae. We analyze all sources within the BU-FCRAO Galactic Ring Survey (GRS) of 13CO emission known…
We present 2.5-square-degree C$_{2}$H N=1-0 and N$_2$H$^+$ J=1-0 maps of the $\rho$ Ophiuchi molecular cloud complex. These are the first large-scale maps of the $\rho$ Ophiuchi molecular cloud complex with these two tracers. The C$_{2}$H…
To provide constraints on the chemical processes responsible for the observed columns of organic species, we used NOEMA to observe the sight line toward NRAO150 in the 2mm spectral window. We targeted the low excitation lines of o-H2CO…
Using the Yebes 40m and IRAM 30m radio telescopes, we detected a series of harmonically related lines with a rotational constant B0=4460.590 +/- 0.001 MHz and a distortion constant D0=0.511 +/- 0.005 kHz towards the cold dense core TMC-1.…
We present high spatial resolution (5.1" x 2.7") OVRO millimeter array observations of HCN (J=1-0) and HCO+ (J=1-0) emission in the inner 3 pc of the galaxy. The HCN and HCO+ emission of the circumnuclear disk (CND) is distributed in a…
We present a comparative study of the physical properties and the spatial distribution of column density peaks in two Giant Molecular Clouds (GMC), the Pipe Nebula and Orion A, which exemplify opposite cases of star cluster formation…
We have carried out wide-field (0.17 degree^2) and high-angular resolution (21.3 arcsec ~ 0.04 pc) observations in [CI] line toward the Orion-A giant molecular cloud with the Atacama Submillimeter Telescope Experiment (ASTE) 10 m telescope…