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Elasticity Of Cylindrical Black Holes, Conrad Pearson 2016 California Polytechnic State University, San Luis Obispo

Elasticity Of Cylindrical Black Holes, Conrad Pearson

Physics

Black holes are regions of strong gravity, and are often regarded as behaving like drops of fluid. When this line of thought is applied to cylindrical black holes (black cylinders), a mapping can be made between known instabilities for black cylinders and ordinary fluid cylinders. However, this known correlation is increasingly less accurate for lower spatial dimensions, and I seek to correct this discrepancy in this thesis. By considering soft solids instead of pure fluids, elastic energy can be included, which brings us closer to a direct comparison. In improving this mapping, it becomes possible to better understand the behavior ...


Maple Worksheet For The Tt Decomposition Of Gravitational Waves, Jeffrey S. Hazboun 2016 Utah State University

Maple Worksheet For The Tt Decomposition Of Gravitational Waves, Jeffrey S. Hazboun

Jeffrey Hazboun

No abstract provided.


Kelt-10b: The First Transiting Exoplanet From The Kelt-South Survey - A Hot Sub-Jupiter Transiting A V=10.7 Early G-Star, R. B. Kuhn, J. E. Rodriguez, K. A. Collins, M. B. Lund, R. J. Siverd, K. D. Colón, J. Pepper, K. G. Stassun, P. A. Cargile, D. J. James, K. Penev, G. Zhou, D. Bayliss, T. G. Tan, I. A. Curtis, S. Udry, D. Segransan, D. Mawet, S. Dhital, J. Soutter, R. Hart, B. Carter, B. S. Gaudi, G. Myers, T. G. Beatty, J. D. Eastman, D. E. Reichart, J. B. Haislip, J. F. Kielkopf, A. Bieryla, D. W. Latham, Eric L.N. Jensen, T. E. Oberst, D. J. Stevens 2016 Swarthmore College

Kelt-10b: The First Transiting Exoplanet From The Kelt-South Survey - A Hot Sub-Jupiter Transiting A V=10.7 Early G-Star, R. B. Kuhn, J. E. Rodriguez, K. A. Collins, M. B. Lund, R. J. Siverd, K. D. Colón, J. Pepper, K. G. Stassun, P. A. Cargile, D. J. James, K. Penev, G. Zhou, D. Bayliss, T. G. Tan, I. A. Curtis, S. Udry, D. Segransan, D. Mawet, S. Dhital, J. Soutter, R. Hart, B. Carter, B. S. Gaudi, G. Myers, T. G. Beatty, J. D. Eastman, D. E. Reichart, J. B. Haislip, J. F. Kielkopf, A. Bieryla, D. W. Latham, Eric L.N. Jensen, T. E. Oberst, D. J. Stevens

Physics & Astronomy Faculty Works

We report the discovery of KELT-10b, the first transiting exoplanet discovered using the KELT-South telescope. KELT-10b is a highly inflated sub-Jupiter mass planet transiting a relatively bright V = 10.7 star (TYC 8378-64-1), with Teff = 5948 ± 74 K, log g = 4.319_{-0.030}^{+0.020} and [Fe/H] = 0.09_{-0.10}^{+0.11}, an inferred mass M = 1.112_{-0.061}^{+0.055} M and radius R = 1.209_{-0.035}^{+0.047} R. The planet has a radius Rp = 1.399_{-0.049}^{+0.069} RJ and mass Mp = 0.679_{-0.038 ...


X-Ray Populations In The Local Group: Insights With Hubble & Chandra, Neven Vulic 2016 The University of Western Ontario

X-Ray Populations In The Local Group: Insights With Hubble & Chandra, Neven Vulic

Electronic Thesis and Dissertation Repository

X-ray observations provide a unique perspective on the most energetic processes in the Universe. In particular, Low-mass X-ray binaries (LMXBs) found in globular clusters have been shown to depend on the mass, radius, and metallicity of the cluster. This thesis focuses on the impact environmental parameters have on X-ray sources and the underlying physical explanations for them.

I studied the X-ray binary population in M31 using 1 Ms of Chandra ACIS data and 6-filter photometry from the Panchromatic Hubble Andromeda Treasury Survey. From a sample of 83 star clusters we found the brightest and most compact star clusters preferentially hosted ...


Teaching Big History, Richard B. Simon, Mojgan Behmand, Thomas Burke, Esther Quaedackers, Seohyung Kim, Kiowa Bower, Neal Wolfe, James B. Cunningham, Cynthia Taylor, Martin Anderson, J. Daniel May, Philip Novak, Debbie Daunt, Jaime Castner, Ethan Annis, Amy E. Gilbert, Anne Reid, Suzanne Roybal, Alan Schut, Cynthia Brown, Harlan Stelmach 2016 Department of Literature and Languages, Dominican University of California

Teaching Big History, Richard B. Simon, Mojgan Behmand, Thomas Burke, Esther Quaedackers, Seohyung Kim, Kiowa Bower, Neal Wolfe, James B. Cunningham, Cynthia Taylor, Martin Anderson, J. Daniel May, Philip Novak, Debbie Daunt, Jaime Castner, Ethan Annis, Amy E. Gilbert, Anne Reid, Suzanne Roybal, Alan Schut, Cynthia Brown, Harlan Stelmach

Harlan Stelmach

Big History is a new field on a grand scale: it tells the story of the universe over time through a diverse range of disciplines that spans cosmology, physics, chemistry, astronomy, geology, evolutionary biology, anthropology, and archaeology, thereby reconciling traditional human history with environmental geography and natural history.Weaving the myriad threads of evidence-based human knowledge into a master narrative that stretches from the beginning of the universe to the present, the Big History framework helps students make sense of their studies in all disciplines by illuminating the structures that underlie the universe and the connections among them.Teaching Big ...


Black Holes Modeled As Fluid Droplets On Membranes, Anthony Bardessono 2016 California Polytechnic State University, San Luis Obispo

Black Holes Modeled As Fluid Droplets On Membranes, Anthony Bardessono

Physics

No abstract provided.


Microfabrication With Smooth, Thin Cnt/Polymer Composite Sheets, Nathan Edward Boyer 2016 Brigham Young University - Provo

Microfabrication With Smooth, Thin Cnt/Polymer Composite Sheets, Nathan Edward Boyer

All Theses and Dissertations

Carbon nanotube (CNT)/polymer composite sheets can be extremely high strength and lightweight, which makes them attractive for fabrication of mechanical structures. This thesis demonstrates a method whereby smooth, thin CNT/polymer composite sheets can be fabricated and patterned on the microscale using a process of photolithography and plasma etching. CNT/polymer composites were made from CNTs grown using chemical vapor deposition using supported catalyst growth and floating catalyst growth. The composite sheets had a roughness of approximately 30nm and were about 61¼m or 261¼m depending on whether they were made from supported catalyst grown or floating catalyst grown CNTs ...


Microfabrication With Smooth, Thin Cnt/Polymer Composite Sheets, Nathan Edward Boyer 2016 Brigham Young University - Provo

Microfabrication With Smooth, Thin Cnt/Polymer Composite Sheets, Nathan Edward Boyer

All Student Publications

Carbon nanotube (CNT)/polymer composite sheets can be extremely high strength and lightweight, which makes them attractive for fabrication of mechanical structures. This thesis demonstrates a method whereby smooth, thin CNT/polymer composite sheets can be fabricated and patterned on the microscale using a process of photolithography and plasma etching. CNT/polymer composites were made from CNTs grown using chemical vapor deposition using supported catalyst growth and floating catalyst growth. The composite sheets had a roughness of approximately 30nm and were about 61¼m or 261¼m depending on whether they were made from supported catalyst grown or floating catalyst grown CNTs ...


Medieval Cosmology And Middle-Earth: A Lewisian Walk Under Tolkienian Skies, Kristine Larsen 2016 Central Connecticut State University

Medieval Cosmology And Middle-Earth: A Lewisian Walk Under Tolkienian Skies, Kristine Larsen

Journal of Tolkien Research

A nearly identical version of this paper was delivered at the 30th Annual International Conference on Medievalism in Pittsburgh, Pennsylvania on October 2, 2015, as part of a session on the Inklings and Medievalism.


Contributing To Astropy: A Community Python Library For Astronomers, Asra Nizami 2016 Macalester College

Contributing To Astropy: A Community Python Library For Astronomers, Asra Nizami

Macalester Journal of Physics and Astronomy

This paper discusses the author’s contributions to two packages affiliated with Astropy, a community Python library for astronomers. The packages the author contributed to were modeling, a sub-package within the core Astropy package, and WCSAxes, an Astropy affiliated package, outside the core package.


Energetic Behavior Of Resistive Random-Access Memory Cells, Christopher M. Bisbee 2016 Macalester College

Energetic Behavior Of Resistive Random-Access Memory Cells, Christopher M. Bisbee

Macalester Journal of Physics and Astronomy

In order to investigate the switching characteristics of Resistive Random Access Memory cells (ReRAM) in terms of their thermodynamic free energy properties, we need to build a number of models that replicate the system. This report contains the models used to investigate filament growth patterns based on different boundary conditions applied to the electrode-filament system. Using Comsol Multiphysics software, we determined that when a fixed voltage is applied to each electrode in the electrode-filament system, we should expect filament dissolution that resets our cells into the High Resistance State (HRS). If we instead fix a set amount of charge on ...


Teaching Numerical Methods In The Context Of Galaxy Mergers, Maria Kourjanskaia 2016 California Polytechnic State University, San Luis Obispo

Teaching Numerical Methods In The Context Of Galaxy Mergers, Maria Kourjanskaia

Physics

Methods of teaching numerical methods to solve ordinary differential equations in the context of galaxy mergers were explored. The research published in a paper by Toomre and Toomre in 1972 describing the formation of galactic tails and bridges from close tidal interactions was adapted into a project targeting undergraduate physics students. Typically undergraduate physics students only take one Computational Physics class in which various techniques and algorithms are taught. Although it is important to study computational physics techniques, it is just as important to apply this knowledge to a problem that is representative of what computational physics researchers are investigating ...


Schwarzschild Spacetime And Friedmann-Lemaitre-Robertson-Walker Cosmology, Zachary Cohen 2016 University of Connecticut - Storrs

Schwarzschild Spacetime And Friedmann-Lemaitre-Robertson-Walker Cosmology, Zachary Cohen

Honors Scholar Theses

The advent of General Relativity via Einstein's field equations revolutionized our understanding of gravity in our solar system and universe. The idea of General Relativity posits that gravity is entirely due to the geometry of the universe -- that is, the mass distribution throughout the universe results in the ``curving" of spacetime, which gives us the physics we see on a large scale. In the framework of General Relativity, we find that the universe behaves differently than was predicted in the model of gravitation developed by Newton. We will derive the general relativistic model for a simple system near a ...


Extending The Supermassive Black Hole Mass-Pitch Angle Relation To Moderate Redshifts, Logan H. Jones 2016 University of Arkansas, Fayetteville

Extending The Supermassive Black Hole Mass-Pitch Angle Relation To Moderate Redshifts, Logan H. Jones

Physics Undergraduate Honors Theses

I extend the empirical correlation between central supermassive black hole mass M and spiral arm pitch angle P in spiral galaxies to intermediate redshifts using a sample of 14 type 1 Seyfert galaxies. Nuclear black hole masses are measured from the widths and luminosities of the broad Hβ and MgII emission lines, and pitch angles are measured using two independent image analysis techniques. I find the best-fit relation log(M/M☉) = (8.31 ± 0.28) − (0.058 ± 0.016)P, which indicates little to no evolution compared to the published M-P relation for local spirals.


Star Formation In Ring Galaxies, Susan C. Olmsted 2016 East Tennessee State Universtiy

Star Formation In Ring Galaxies, Susan C. Olmsted

Undergraduate Honors Theses

Ring galaxies are specific types of interacting galaxies in which a smaller galaxy has passed through the center of the disk of another larger galaxy. The intrusion of the smaller galaxy causes the structure of the larger galaxy to compress as the smaller galaxy falls through, and to recoil back after the smaller galaxy passes through, hence the ring-like shape. In our research, we studied the star-forming regions of a sample of ring galaxies and compared to those of other interacting galaxies and normal galaxies. Using UV, optical, and IR archived images in twelve wavelengths from three telescopes, we analyzed ...


The Inner Gaseous Disks Of Herbig Be Stars, Parshati Patel 2016 The University of Western Ontario

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 ...


Insights From Unsupervised Clustering And Composite Spectral Analysis Into The Physical Properties Driving Emission And Absorption In Quasar Uv/Optical Spectra, Aycha Tammour 2016 The University of Western Ontario

Insights From Unsupervised Clustering And Composite Spectral Analysis Into The Physical Properties Driving Emission And Absorption In Quasar Uv/Optical Spectra, Aycha Tammour

Electronic Thesis and Dissertation Repository

Although quasar spectra appear remarkably similar, subtle systematic differences are well- known and are linked to the physical conditions in the emitting regions. This thesis char- acterizes the properties of quasar optical and UV spectral features and reveals some of their underlying physical causes by analyzing large spectroscopic datasets from the Sloan Digital Sky Survey.

We first examine the narrow-line region using four optical emission lines with a range of ionization potentials (IPs) using a sample of 16,027 quasars with redshift z ≤ 0.75. We bin the sample using the continuum luminosity and the Hβ width to constrain the ...


Nucleosynthesis In Core-Collapse Supernovae, Rachel E Mersch 2016 University of Tennessee, Knoxville

Nucleosynthesis In Core-Collapse Supernovae, Rachel E Mersch

EURēCA: Exhibition of Undergraduate Research and Creative Achievement

A Core-Collapse Supernova explosion occurs when nuclear fusion stops in the core of a massive star. Without a source of energy supplying enough pressure to balance gravity, the core becomes unstable and collapses to form a neutron star. Beyond the neutron star, a shockwave forms which moves outward through the star, causing heavier elements to be created through nuclear fusion. We have been studying the elements that are ejected from a Core-Collapse Supernova using a nuclear code network called XNet, which follows the thermonuclear kinetics. We use the results from a code called Chimera, which explores the mechanism of Core-Collapse ...


Better Together, 2016 DePaul University

Better Together

DePaul Magazine

Faculty have taken full advantage of the university's innovative intercollegiate grant program, and the resulting research is as interesting and diverse as the collaborators themselves. What is resulting is research on "Patient and Primary Care Provider Perspectives on Recreational and Therapeutic Cannabis Use Within a Changing Socioculltural and Political Context;" a new minor in climate change science and policy; a new class, Communication, Coding and Entrepreneurship; brain inflammation research; and the project "Cosmology Meets Continental Philosophy: Natural Laws and Why There Is Something Rather Than Nothing"


The Parallelization And Optimization Of The N-Body Problem Using Openmp And Openmpi, Nicholas J. Carugati 2016 Gettysburg College

The Parallelization And Optimization Of The N-Body Problem Using Openmp And Openmpi, Nicholas J. Carugati

Student Publications

The focus of this research is exploring the efficient ways we can implement the NBody problem. The N-Body problem, in the field of physics, is a problem in which predicts or simulates the movements of planets and how they interact with each other gravitationally. For this research, we are viewing if the simulation can execute efficiently by delegating the heavy computational work through different cores of a CPU. The approach that is being used to figure this out is by integrating the parallelization API OpenMP and the message-passing library OpenMPI into the code. Rather than all the code executing on ...


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