Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 9 of 9 for “"circumstellar environments"”.
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Circumstellar environments around the youngest protostars: interferometric observations and modeling
… collapse inside their natal envelopes, and these circumstellar envelopes contain valuable information about the physical processes of star formation. In this thesis, both molecular lines and dust continuum are utilized to investigate the nature of the collapsing envelopes. In particular, I focus …
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Silicon Oxide Nanoparticles Reveal the Origin of Silicate Grains in Circumstellar Environments
The processes leading to the widespread presence of crystalline silicates throughout the galaxy and the origin of silicon nanoparticles thought to be responsible for the observed extended red emission in diffuse galactic background are still far from being understood. One of the most abundant …
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High resolution linear spectropolarimetry: a study of the potentiality in probing stellar atmospheres and circumstellar environments
… technique for a variety of astrophysical environments. Many phenomena, in fact, can contribute to the polarisation of radiation and so, its observation can potentially provide information about their basic causes. In particular, in a stellar context high resolution spectropolarimetry can …
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The transfer of polarized radiation in astrophysical masers in the presence of magnetic fields
… physical conditions in both star forming and circumstellar environments. Calculations are performed which give the spectra of the emergent maser radiation for different magnetic fields, radiative intensities, decay rates, and pumping rates thought to be appropriate in astrophysical masing …
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Study of fullerene-based molecular nanostructures in planetary nebulae
… and graphene (possible C24) in the H-rich circumstellar environments of evolved stars indicate that these complex molecules are not so rare and have raised the idea that other forms of carbon such as hydrogenated fullerenes (fulleranes), buckyonions, and carbon nanotubes may be widespread …
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Photometric monitoring of early type emission line stars
… source catalogue, are analysed to probe the circumstellar environments of these objects and to determine the extent and causes of optical variability in such stars. It was found that many of these stars are associated with warm circumstellar dust and that the mean temperature of that dust is …
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The transfer of polarized radiation in astrophysical masers in the presence of magnetic fields
Restriction data tranferred 2014-07-01T11:13:46-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: Thesis
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Microanalytical Investigations of Presolar SiC Grains as Probes of Condensation Conditions in Astrophysical Environments
… in several different types of astrophysical environments, including asymptotic giant branch: AGB) stars, J stars, born-again AGB stars, and Type II supernovae: SNe). The isotopic compositions and microstructural properties of a large number of presolar grains have previously been measured, …
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Meshless hydrodynamic simulations of young supernova remnants
… collision of their ejecta with the surrounding circumstellar medium results in the formation of supernova remnants that have been detected at all wavelengths, from radio to gamma-rays. For several dozen supernova remnants, very-long-baseline radio interferometers have spatially resolved the …