Results 41 to 50 of about 238,168 (251)
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
Understanding the Kinetic Energy Deposition within Molecular Clouds
The Astrophysical Journal, 2023 According to the structures traced by ^13 CO spectral lines within ^12 CO molecular clouds (MCs), we investigate the contributions of their internal gas motions and relative motions to the total velocity dispersions of ^12 CO MCs. Our samples of 2851 ^12
Lixia Yuan +10 more
doaj +1 more source
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
Submillimeter and Far-Infrared Polarimetric Observations of Magnetic Fields in Star-Forming Regions
Frontiers in Astronomy and Space Sciences, 2019 Observations of star-forming regions by the current and upcoming generation of submillimeter polarimeters will shed new light on the evolution of magnetic fields over the cloud-to-core size scales involved in the early stages of the star formation ...
Kate Pattle, Laura Fissel
doaj +1 more source
HCO+ in dark molecular clouds [PDF]
Serbian Astronomical Journal, 2007 Formyl ion is one of the most important molecules, and primary molecular ion to be found in molecular clouds. This paper reviews chemical pathways of formation and destruction of the molecule, as well as its use as a tool in the study of dark molecular ...
Nikolić S.
doaj +1 more source
Rapid Formation of Molecular Clouds and Stars in the Solar Neighborhood [PDF]
Astrophys.J.562:852-868,2001, 2001 Observations of both star-forming regions and young, gas-free stellar associations indicate that most nearby molecular clouds form stars only over a short time span before dispersal; large-scale flows in the diffuse interstellar medium have the potential for forming clouds sufficiently rapidly, and for producing stellar populations with ages much less ...
arxiv +1 more source
Molecular clouds in the center of M 81 [PDF]
Astronomy & Astrophysics, 2007 We investigate the molecular gas content and the excitation and fragmentation properties in the central region of the spiral galaxy Messier 81 in both the ^{12}CO(1-0) and ^{12}CO(2-1) transitions. We have recently observed the two transitions of CO in the M~81 center with A, B, and HERA receivers of the IRAM 30-m telescope.
CASASOLA, VIVIANA +3 more
openaire +7 more sources
ASTROCHEMICAL CORRELATIONS IN MOLECULAR CLOUDS [PDF]
The Astrophysical Journal, 2015 Accepted by ApJ.
Erik Rosolowsky +4 more
openaire +4 more sources
On the Spatial Distribution of 13CO Structures within 12CO Molecular Clouds
The Astrophysical Journal, 2023 We look into the 2851 ^12 CO molecular clouds harboring ^13 CO structures to reveal the distribution of the projected angular separations and radial velocity separations between their internal ^13 CO structures.
Lixia Yuan +10 more
doaj +1 more source
ALMA view of the Galactic Center 50km/s molecular cloud [PDF]
, 2016 We have observed the Galactic Center 50km/s molecular cloud (50MC) with ALMA to search for filamentary structures. In the CS J=2-1 emission line channel maps, we succeeded in identifying 27 molecular cloud filaments using the DisPerSE algorithm. This is the first attempt of "filament-finding" in the Galactic Center Region.
arxiv +1 more source