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Showing 1 to 20 of 33 for “"Molecular Cloud"”.
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The G332 Molecular Cloud
… study and physical analysis of a new Giant Molecular Cloud (GMC) discovered using a survey of the Galactic Plane in the lines of the carbon monoxide isotopologues (12CO, 13CO, C18O J = 1 → 0) undertaken with the 22m Mopra radio telescope (Mopra CO Southern Galactic Plane Survey, Mopra CO …
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A multi-molecular line study of an entire giant molecular cloud
… Presented here are the results of multi-molecular lines mapping of the entire giant molecular cloud G333, comprised sites of low- and high-mass star forming regions in various evolution stages of star formation. The result shows the spatial distribution of CS, HCO+, HCN and HNC are …
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Gas distribution, star formation and giant molecular cloud evolution in nearby spiral galaxies
… the whole galactic disk to the size of the Giant Molecular Clouds (GMCs). Differences in the shape and width of global CO and HI spectra of resolved disks of spiral galaxies are systematically investigated using a nearby sample for which high-resolution CO and HI maps are available. I find that CO …
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Interferometric studies of 3 millimeter continuum and molecular lines in the giant molecular cloud Sagittarius B2
The giant molecular cloud Sagittarius B2 is known for its active role in chemical evolution, massive star formation, and complex kinematic structure. Studies of the 3 mm continuum and the transitions of various molecular species are essential in understanding not only the chemical evolution but …
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Star formation in the presence of magnetic fields: Molecular cloud core formation and dynamical contraction due to ambipolar diffusion; a simulation with axial symmetry
Interstellar molecular clouds are generally believed to be the sites of active star formation in our galaxy. Observed densities, temperatures, and magnetic field strengths imply that well-ordered magnetic fields dominate thermal pressure in supporting these objects against self-gravity. The …
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Multifluid Kelvin-Helmholtz instability in weakly ionised astrophysical plasmas
… of a protostellar jet and its surrounding molecular cloud. In particular, changes to the development of the KH instability as a result of including the multlifluid effects of ambipolar diffusion and the Hall effect are isolated and individually studied in chapters 4 and 5 respectively. …
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New Molecular Probes of Astronomical Sources (Interstellar Sources, Comets)
… for refining the knowledge of astronomical molecular sources. The primary project involved HCO in interstellar molecular clouds. The observational results include the verification of the identity of interstellar HCO, the confirmation of the C('+)-HCO correlation first suggested by Snyder, …
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Molecular gas in S106: Morphology, kinematics, and chemistry of a star-forming region
… lobes flowing out from a central disk of cold molecular gas in which is embedded the newly formed massive star IRS 4. This entire complex is still embedded in the molecular cloud from which it formed.
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Stochastic histories of dust grains in the interstellar medium
… the diffuse phase and accretion within the cold molecular cloud phase. In order to record chemical detail, we take each new particle to consist of a superrefractory core plus a more massive refractory mantle. The particles are allowed to transfer to and fro between the different phases of the ISM …
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Protostar Formation in Magnetic Clouds: The Phase Beyond Ion Detachment
"We follow the formation and evolution of a molecular cloud core from mean molecular cloud densities to a density enhancement of twelve orders of magnitude, by which stage the magnetic flux problem of star formation is expected to be resolved. We use the nonideal six-fluid MHD equations, which we …
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Orion B--Anatomy of a Star-Forming Region
The compact HII region/molecular cloud Orion B was observed with the VLA in the radio continuum and OH absorption line at a frequency of 1667 MHz, in the near-infrared continuum and H$\sb2$ emission line at a wavelength of 2 $\mu$m, and in several millimeter-wavelength molecular transitions (of …
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From Large-scale Molecular Clouds to Filaments and Cores : Unveiling the Role of the Magnetic Fields in Star Formation
… fields in characterizing the structure of molecular clouds. We run three-dimensional turbulent non-ideal magnetohydrodynamic simulations (with ambipolar diffusion) to see the effect of magnetic fields on the evolution of the column density probability distribution function (PDF). Our …
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The relation between atomic and molecular gas: the Magellanic Clouds and beyond
… interferometry imaging, to study the atomic and molecular gas relation in the Large/Small Magellanic Clouds and 43 nearby galaxies. These galaxies demonstrate various galactic environments compared with the Milky Way and provide an ideal sample for testing the cloud-scale and galactic-scale …
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Interpreting the 10um astronomical silicate feature
… towards field and embedded objects in the Taurus Molecular Cloud (TMC) were obtained with CGS3 at the United Kingdom Infrared Telescope (UKIRT). Cold molecular-cloud silicates are sampled in quiescent lines of sight towards the field stars Taurus-Elias 16 and Elias 13, whilst observations of the …
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The Effects of Fractal Molecular Clouds on the Dynamical Evolution of Oort Cloud Comets
The Oort Cloud (OC) is a roughly spherical cloud of comets surrounding the solar system, stretching from well beyond the orbit of Neptune, half way to the nearest star. This body of comets is interesting because it contains a record of the gravitational perturbations suffered by the solar system …
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The Next Generation Balloon-Borne Large Aperture Submillimeter Telescope (blast-Tng)
… posed by submillimeter polarimetry, the study of molecular cloud dynamics and star formation remain stunted. Previously, polarimetry data was limited to a few vectors on only the brightest areas of molecular clouds. This made drawing statistically-driven conclusions a daunting task. However, the …
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Present and early star formation : a study on rotational and thermal properties
… and thermal properties of star-forming molecular clouds using hydrodynamic simulations. Stars form from molecular cloud cores by gravoturbulent fragmentation. Understanding the angular momentum and the thermal evolution of cloud cores thus plays a fundamental role in completing the …
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Propagation of molecular outflows into inhomogeneous media
Molecular clouds have inhomogeneous density profiles and have been observed to be `clumpy' in nature, containing dense cores, rarefied filaments and cocoons. Energetic mass-ejection phenomena created during the gravitational collapse of dense cores are thought to be responsible for the molecular …
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Search for evidence of cosmic ray acceleration by supernova Remnant Kes 41 using the Fermi LAT
… that from other calculations involving SNR-Molecular cloud interaction [22]. This interaction serves to constrain [gamma]-ray emission to the [pi]⁰-decay channel, so evidence of a similar density value may be evidence that the significant [gamma]-ray emission observed, was due to the …
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