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Articles 1 - 11 of 11
Full-Text Articles in Physical Processes
Searching For Temporal Variations In The Fine-Structure Constant Using Espresso Spectrograph Data, David Hoffman Iv
Searching For Temporal Variations In The Fine-Structure Constant Using Espresso Spectrograph Data, David Hoffman Iv
Senior Theses
The fine-structure constant α is a dimensionless constant, defined as e²/(4πε₀ℏc) ≈ 1/137. On the order of human timescales, its value is very much unchanging, however, in recent years there has been extensive debate over whether or not the value of α has remained constant over cosmological timescales. With the natural corollary to a changing α being that either one or multiple of its constituent physical constants have also changed in value, observing a variation in the fine-structure constant would have vast ramifications for our understanding of the nature of the early universe and how it has evolved. While past …
Empirical Validation Of Einstein’S Coefficient For The Deflection Of Light Due To Gravitational Forces, Alexandra R. Mcdowell
Empirical Validation Of Einstein’S Coefficient For The Deflection Of Light Due To Gravitational Forces, Alexandra R. Mcdowell
Honors College Theses
Einstein’s formula to calculate the deflection angle of light through space as it interacts with gravity was introduced in his 1916 publication on general relativity. This was not a new idea, but his equation was, and it was correct. Just 3 years after this publication, it was empirically validated by Sir Arthur Eddington and Sir Frank Dyson. Since that experiment in 1919, at least seven others have been performed that also gave definitive answers in support of Einstein’s deflection constant of 1.751 arcseconds. The two most recent ones made groundbreaking contributions to this effort. The 2017 eclipse showed reproducible results …
Exploring The Hot And Gaseous Universe From Infrared To X-Ray, Chamani Gunasekera
Exploring The Hot And Gaseous Universe From Infrared To X-Ray, Chamani Gunasekera
Theses and Dissertations--Physics and Astronomy
Over 90% of baryonic matter in the universe exists as astrophysical plasmas. The gas
is often far from thermodynamic equilibrium, so numerical non-equilibrium spectral
synthesis simulations are used to understand observations. cloudy simulates vari-
ous physical conditions, providing spectra predictions. This thesis aims to meet the
challenge of new observatories like the JWST (James Webb Space Telescope) and
XRISM (X-Ray Imaging Spectroscopy Mission). These simulations are no better
than the underlying atomic and molecular database and the fourth chapter details
a long-needed update to an evolving database. The predicted spectra are strongly
affected by the composition of the gas, which …
Comet Nuclei Activity Simulation Using Percolation Theory On Comet 67p/Churyumov– Gerasimenko, Ahmad Sohani
Comet Nuclei Activity Simulation Using Percolation Theory On Comet 67p/Churyumov– Gerasimenko, Ahmad Sohani
Theses and Dissertations
Comets, remnants of the solar system's formation, exhibits partially unexplained outbursts that are closely tied to the physical structure of the nucleus. To investigate outbursts, we employed pore network modeling techniques, such as the Bower-Watson algorithm and Voronoi diagrams, to better represent the nucleus' complex porous structure and simulate gas transfer processes. We examined heat diffusion in the comet's subsurface and its influence on crystallization. The extra heat generated by crystallization can shift the crystalline front deeper into the nucleus, accelerating subsurface evaporation rates. This process results in the formation of a thicker ice mantle with reduced porosity on the …
Solar Radio Burst Type Ii And Iii With Half Wave Dipole Antenna, Mohd Pauzi Farah Aqilah
Solar Radio Burst Type Ii And Iii With Half Wave Dipole Antenna, Mohd Pauzi Farah Aqilah
Student Works (2020-2029)
An investigation into the physics of solar radio burst type II was done to understand the frequency gap between its fundamental and harmonic emissions that happen as aftershocks of Coronal Mass Ejection (CME). Up until now, the evolution of type II and its associated coronal wave still remain a mystery. Hazardous CME study upholds its fore coming danger to human and technology. This work also addresses the issue of the lack of spatial resolution of previous solar radio burst type II studies. An instrument produced by ETH Zürich namely the Compound Astronomical Low-cost Low-frequency Instrument for Spectroscopy and Transportable Spectrometers …
Automated Spectroscopic Detection And Mapping Using Alma And Machine Learningtechniques, Steven Cocke, Andrew Wilkins, Josephine Mcdaniel, John Santerre, Conor Nixon
Automated Spectroscopic Detection And Mapping Using Alma And Machine Learningtechniques, Steven Cocke, Andrew Wilkins, Josephine Mcdaniel, John Santerre, Conor Nixon
SMU Data Science Review
In this paper we present a methodology for automating theclassification of spectrally resolved observations of multiple emissionlines with the Atacama Large Millimeter/submillimeter Array (ALMA).Molecules in planetary atmospheres emit or absorb different wavelengthsof light thereby providing a unique signature for each species. ALMAdata were taken from interferometric observations of Titan made be-tween UT 2012 July 03 23:22:14 and 2012 July 04 01:06:18 as part ofALMA project 2011.0.00319.S. We first employed a greedy set cover algorithm to identify the most probable molecules that would reproducethe set of frequencies with respective flux greater than 3σaway from themean. We then selected a subset of …
Preparing A Database Of Extremely High Velocity Outflows In Quasars, Griffin Kowash, Carla P. Quintero, Sean S. Haas, Paola Rodriguez Hidalgo
Preparing A Database Of Extremely High Velocity Outflows In Quasars, Griffin Kowash, Carla P. Quintero, Sean S. Haas, Paola Rodriguez Hidalgo
IdeaFest: Interdisciplinary Journal of Creative Works and Research from Cal Poly Humboldt
No abstract provided.
Determining The Location Of The Coronal Line Region Within Local Active Galactic Nuclei Using [Fe Vii] Emission Line Properties, Charles Grant Showley
Determining The Location Of The Coronal Line Region Within Local Active Galactic Nuclei Using [Fe Vii] Emission Line Properties, Charles Grant Showley
Physics
Given a sample of 99 local AGNs, we study the characteristics of the forbidden [Fe VII] coronal line for the purpose of determining the location of the coronal line region (CLR) within the AGN. We calculate the velocity of the clouds emitting [Fe VII] using the width of the [Fe VII] emission lines compared to [O II] emission lines to establish whether the clouds are inflowing or outflowing. We plot the [Fe VII] and [O II] flux ratios against the AGNs' known black hole masses and stellar velocity dispersions in order to see if there are any correlations between them. …
Supernova Resonance-Scattering Line Profiles In The Absence Of A Photosphere, Brian Friesen, E. Baron, David Branch, Bin Chen, Jerod T. Parrent, R. C. Thomas
Supernova Resonance-Scattering Line Profiles In The Absence Of A Photosphere, Brian Friesen, E. Baron, David Branch, Bin Chen, Jerod T. Parrent, R. C. Thomas
Dartmouth Scholarship
In supernova (SN) spectroscopy relatively little attention has been given to the properties of optically thick spectral lines in epochs following the photosphere's recession. Most treatments and analyses of post-photospheric optical spectra of SNe assume that forbidden-line emission comprises most if not all spectral features. However, evidence exists that suggests that some spectra exhibit line profiles formed via optically thick resonance-scattering even months or years after the SN explosion. To explore this possibility, we present a geometrical approach to SN spectrum formation based on the "Elementary Supernova" model, wherein we investigate the characteristics of resonance-scattering in optically thick lines while …
Using Maxwells Z Model To Determine Lunar Mare Lava Thickness, Autumn Wille
Using Maxwells Z Model To Determine Lunar Mare Lava Thickness, Autumn Wille
Honors Capstones
Capstone submitted as a graduate requirement for the BSU Honors Program.
Comets And Meteors, Lincoln N. Oatley
Comets And Meteors, Lincoln N. Oatley
Student and Lippitt Prize Essays
Defines and describes named comets and meteor events and their scientific study.