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Full-Text Articles in Astrophysics and Astronomy
Emplacement Of The Foy, Hess And Pele Offset Dykes At The Sudbury Impact Structure, Canada, Eric A. Pilles
Emplacement Of The Foy, Hess And Pele Offset Dykes At The Sudbury Impact Structure, Canada, Eric A. Pilles
Electronic Thesis and Dissertation Repository
The 1.85 Ga Sudbury impact structure is the remnant of what is generally considered to have been an ~150–200 km diameter impact basin in central Ontario, Canada. The so-called Offset Dykes are impact melt dykes that are found concentrically around – and extending radially outward from – the Sudbury Igneous Complex (SIC), a ~3 km thick differentiated impact melt sheet. The dykes are typically composed of two main phases of granodiorite: an inclusion- and sulfide-rich granodiorite in the centre of the dyke, and an inclusion- and sulfide-poor granodiorite along the margins of the dyke. This study uses a combination of …
Dicke’S Superradiance In Astrophysics, Fereshteh Rajabi
Dicke’S Superradiance In Astrophysics, Fereshteh Rajabi
Electronic Thesis and Dissertation Repository
It is generally assumed that in the interstellar medium much of the emission emanating from atomic and molecular transitions within a radiating gas happen independently for each atom or molecule, but as was pointed out by R. H. Dicke in a seminal paper several decades ago this assumption does not apply in all conditions. As will be discussed in this thesis, and following Dicke’s original analysis, closely packed atoms/molecules can interact with their common electromagnetic field and radiate coherently through an effect he named superradiance. Superradiance is a cooperative quantum mechanical phenomenon characterized by high intensity, spatially compact, burst-like features …
The Inner Gaseous Disks Of Herbig Be Stars, Parshati Patel
The Inner Gaseous Disks Of Herbig Be Stars, Parshati Patel
Electronic Thesis and Dissertation Repository
Herbig Ae/Be stars are intermediate mass (~2 to 20Msun) pre-main sequence stars that inherit a circumstellar disk of dust and gas from their formation phase. The region of this disk closest to the star is entirely gaseous because dust evaporates at the high temperatures there, and this gaseous region is currently poorly understood. Using non-LTE circumstellar disk codes to model the optical and near-infrared spectra of five, early-type (B0Ve to B2Ve) Herbig Be stars obtained with the Canada-France-Hawaii telescope ESPaDOnS instrument, the density structure of each inner gaseous disks was determined and estimates of the disk masses and …