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Full-Text Articles in Instrumentation
Systematical Uncertainties In The Measurement Of A Gamma-Ray Burst’S Isotropic Equivalent Energy, Kimberly Zoldak
Systematical Uncertainties In The Measurement Of A Gamma-Ray Burst’S Isotropic Equivalent Energy, Kimberly Zoldak
Graduate Theses and Dissertations
Gamma-ray Bursts (GRBs) are the most energetic and luminous explosions in the Universe since the Big Bang, enabling them to be observed out to extremely large redshifts (z~9). Consequently, this makes them a promising cosmological standard candle candidate. Unfortunately, however, they have proven to be quite challenging to standardize. The GRB community has worked tirelessly at this task, and to date, has put forth several luminosity-distance relations, some more propitious than others. The most prevailing problem with these relations is in their sizable amount of scatter, likely due to measurement inconsistencies and errors in the variables they employ. This arises …
Testing Spiral Density-Wave Theory In Disk Galaxies Using Multi-Wavelength Image Data, Star Formation History Maps And Spatially Resolved Stellar Clusters, Mohamed Shameer Abdeen
Testing Spiral Density-Wave Theory In Disk Galaxies Using Multi-Wavelength Image Data, Star Formation History Maps And Spatially Resolved Stellar Clusters, Mohamed Shameer Abdeen
Graduate Theses and Dissertations
Studying galaxy structures using different wavebands enables us to observe a varietyof intrinsic galactic features and to test the validity of underlying theories in detail. Density wave theory, originally proposed by C.C. Lin and F. Shu (Lin & Shu 1964), explains the nature of the spiral arm patterns in disk galaxies as density waves that propagate through the galactic disk. From spiral galaxies to the rings of Saturn, density wave theory has had success in providing qualitative explanations of disk dynamics. However, it is now widely believed that galactic disks are dissipative systems which raises the question of whether they …