Dependence of Molecular Cloud Samples on Angular Resolution, Sensitivity, and Algorithms [PDF]
, 2022 In this work, we investigate the observational and algorithmic effects on molecular cloud samples identified from position-position-velocity (PPV) space. By smoothing and cutting off the high quality data of the Milky Way Imaging Scroll Painting (MWISP) survey, we extract various molecular cloud samples from those altered data with the DBSCAN (density ...
arxiv +1 more source
Filaments in the Lupus molecular clouds [PDF]
Monthly Notices of the Royal Astronomical Society, 2015 We have studied the filaments extracted from the column density maps of the nearby Lupus 1, 3, and 4 molecular clouds, derived from photometric maps observed with the Herschel satellite. Filaments in the Lupus clouds have quite low column densities, with a median value of $\sim$1.5$\times$10$^{21}$ cm$^{-2}$ and most have masses per unit length lower ...
Davide Elia +23 more
openaire +9 more sources
Molecular Cloud Evolution VI. Measuring cloud ages [PDF]
, 2018 This article has been published in Monthly Notices of the Royal Astronomical Society © 2018 The Author(s). Published by Oxford University Press on behalf of the Royal Astronomical Society.
Ansdell +84 more
core +2 more sources
The Scaleheight of Giant Molecular Clouds is Less than that of Smaller Clouds [PDF]
Astrophys.J. 619 (2005) L159-L162, 2004 We have used an antenna temperature thresholding algorithm on the Bell Laboratories 13CO Milky Way Survey to create a catalog of 1,400 molecular clouds. Of these, 281 clouds were selected for having well-determined kinematic distances. The scaleheight, luminosity, internal velocity dispersion, and size of the cloud sample are analyzed to show that ...
arxiv +1 more source
The Large-scale J=3-2 and J=2-1 CO Emission from M17 and its Implications for Extragalactic CO Observations [PDF]
, 1999 We observed a 10x20 pc region of the molecular cloud M17 in the 12CO and 13CO J=3-2 and J=2-1 transitions to determine their global behavior and to assess the reliability of using ratios of CO line intensities integrated over an entire cloud to determine
Aalto S. +17 more
core +3 more sources
Supernova remnants in molecular clouds [PDF]
AIP Conference Proceedings, 1999 31 pages, 4 figures, revised, in press, ApJ, Feb.
openaire +6 more sources
Light Element Nucleosynthesis in a Molecular Cloud Interacting with a Supernova Remnant and the Origin of Beryllium-10 in the Protosolar Nebula [PDF]
, 2014 The presence of short-lived radionuclides in the early solar system provides important information about the astrophysical environment in which the solar system formed.
de Séréville, Nicolas +2 more
core +2 more sources
Molecular Abundances in the Sgr a Molecular Cloud [PDF]
Symposium - International Astronomical Union, 1992 We have obtained column densities for HCO+, HCO, HCS+, C3H2, HC5N, SiO, OCS, HCOOH, CH3CH2 OH, and CH3CCH toward Sgr A. The fractional abundance of SiO relative to molecular hydrogen in Sgr A is comparable to that for the Orion plateau, ~ 10−7 − 10−8, which may be a typical value for hot clouds.
Yc Minh, William M. Irvine, Per Friberg
openaire +2 more sources
Evidence for a Molecular Cloud Origin for Gamma-Ray Bursts: Implications for the Nature of Star Formation in the Universe [PDF]
, 2001 It appears that the majority of rapidly-, well-localized gamma-ray bursts with undetected, or dark, optical afterglows, or `dark bursts' for short, occur in clouds of size R > 10L_{49}^{1/2} pc and mass M > 3x10^5L_{49} M_{sun}, where L is the isotropic ...
Dal Fiume D. +7 more
core +2 more sources
Chemistry of Molecular Clouds [PDF]
International Astronomical Union Colloquium, 1989 AbstractA discussion is presented of the chemistry of quiescent molecular clouds, and the effects of the presence of polycyclic aromatic hydrocarbon molecules and of cosmic-ray induced ultraviolet photons are examined. A comparison is made with the chemistry occurring in molecular clouds that are subjected to shocks and the differences between ...
openaire +2 more sources