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The "True" Column Density Distribution in Star-Forming Molecular Clouds
(American Astronomical Society, 2009)
We use the COMPLETE Survey's observations of the Perseus star-forming region to assess and intercompare the three methods used for measuring column density in molecular clouds: near-infrared (NIR) extinction mapping; thermal ...
The Perils of Clumpfind: The Mass Spectrum of Substructures in Molecular Clouds
(American Astronomical Society, 2009)
We study the mass spectrum of substructures in the Perseus Molecular Cloud Complex traced by \(^{13}CO(1–0)\), finding that \(dN/dM \ \alpha \ M^{−2.4}\) for the standard Clumpfind parameters. This result does not agree ...
Dense Cores in Perseus: The Influence of Stellar Content and Cluster Environment
(American Astronomical Society, 2009)
We present the chemistry, temperature, and dynamical state of a sample of 193 dense cores or core candidates in the Perseus Molecular cloud and compare the properties of cores associated with young stars and clusters with ...
Detection of HCO+ towards Cygnus OB2 No. 12
(Oxford University Press (OUP), 2000)
HCO+ has been detected for the first time towards the star Cygnus OB2 No. 12 through emission of the 1−0 rotational transition at 89GHz. The CO(J=2−1) transition has also been observed. The observations are consistent with ...
Rotational and Vibrational Excitation of CO Molecules by Collisions with 4 He Atoms
(IOP Publishing, 2002)
Full close-coupled calculations are carried out of the cross sections for energy transfer between rotational levels of carbon monoxide in collision with 4He atoms with energies between 5 and 600 cm-1. At low energies, the ...
Line Imaging of Orion KL at 865 μm with the Submillimeter Array
(IOP Publishing, 2005)
We present the first submm (865 µm) imaging spectral line survey at one arcsecond resolution conducted with the Submillimeter Array toward Orion-KL. Within the two × two GHz bandpasses (lower and upper sidebands, 337.2–339.2GHz ...
Discovery of Water Maser Emission in Five AGNs and a Possible Correlation Between Water Maser and Nuclear 2–10 keV Luminosities
(IOP Publishing, 2006)
We report the discovery of water maser emission in five active galactic nuclei (AGN) with the 100-m Green Bank Telescope (GBT). The positions of the newly discovered masers, measured with the VLA, are consistent with the ...
Submillimeter Array 440 μm/690 GHz Line and Continuum Observations of Orion KL
(IOP Publishing, 2006)
Submillimeter Array observations of Orion-KL at ∼ 1′′ resolution in the 440 µm/690 GHz band reveal new insights about the continuum and line emission of the region. The 440 µm continuum flux density measurement from source ...
Discovery of Water Maser Emission in Eight AGNs with 70 m Antennas of NASA’s Deep Space Network
(IOP Publishing, 2006)
We report the discovery of water maser emission in eight active galactic nuclei (AGN) with the 70-m NASA Deep Space Network (DSN) antennas at Tidbinbilla, Australia and Robledo, Spain. The positions of the newly discovered ...
Discovery of Candidate H2O Disk Masers in Active Galactic Nuclei and Estimations of Centripetal Accelerations
(IOP Publishing, 2009)
Based on spectroscopic signatures, about one-third of known H2O maser sources in active galactic nuclei (AGNs) are believed to arise in highly inclined accretion disks around central engines. These “disk maser candidates” ...