The Power Of Principled Bayesian Methods In The Study Of Stellar Evolution, 2019 Embry-Riddle Aeronautical University
The Power Of Principled Bayesian Methods In The Study Of Stellar Evolution, Ted Von Hippel, David Van Dyk, David Stenning, Elliot Robinson, Elizabeth Jeffery, Nathan Stein, William Jefferys, Erin M. O'Malley
Ted von Hippel
It takes years of effort employing the best telescopes and in- struments to obtain high-quality stellar photometry, astrometry, and spectroscopy. Stellar evolution models contain the experience of life- times of theoretical calculations and testing. Yet most astronomers fit these valuable models to these precious datasets by eye. We show that a principled Bayesian approach to fitting models to stellar data yields substantially more information over a range of stellar astrophysics. We highlight advances in determining the ages of star clusters, mass ratios of binary stars, limitations in the accuracy of stellar models, post-main-sequence mass loss, and the ages of individual ...
Bayesian Analysis For Stellar Evolution With Nine Parameters (Base-9): User's Manual, 2019 Embry-Riddle Aeronautical University
Bayesian Analysis For Stellar Evolution With Nine Parameters (Base-9): User's Manual, Ted Von Hippel, Elliot Robinson, Elizabeth Jeffery, Rachel Wagner-Kaiser, Steven Degennaro, Nathan Stein, David Stenning, William H. Jefferys, David Van Dyk
Ted von Hippel
BASE-9 is a Bayesian software suite that recovers star cluster and stellar parameters from photometry. BASE-9 is useful for analyzing single-age, single-metallicity star clusters, binaries, or single stars, and for simulating such systems. BASE-9 uses Markov chain Monte Carlo and brute-force numerical integration techniques to estimate the posterior probability distributions for the age, metallicity, helium abundance, distance modulus, and line-of-sight absorption for a cluster, and the mass, binary mass ratio, and cluster membership probability for every stellar object. BASE-9 is provided as open source code on a version-controlled web server. The executables are also available as Amazon Elastic Compute Cloud ...
The Disk Structure Of Late Type Galaxies: Determining The Black Hole Mass Function Of Low Surface Brightness Galaxies Through Logarithmic Spiral Arm Pitch Angle Measurement, 2019 University of Arkansas, Fayetteville
The Disk Structure Of Late Type Galaxies: Determining The Black Hole Mass Function Of Low Surface Brightness Galaxies Through Logarithmic Spiral Arm Pitch Angle Measurement, Michael S. Fusco
Theses and Dissertations
This dissertation pertains to the geometric structure of late type (spiral) galaxies, specifically on the relation between the logarithmic spiral pitch angle of the galactic spiral arms with other properties of the galaxy, such as central Supermassive Black Hole (SMBH) mass. Our work continues a study of the Black Hole Mass Function (BHMF) in local galaxies by recording the pitch angles of spiral galaxies with lower surface brightness than were previously included. We also conduct a case study on the structure of an interestingly shaped galaxy, UGC 4599. Previous studies on the topic of spiral arm pitch angles have measured ...
Phase Retrieval Using A Genetic Algorithm On The Systematic Image-Based Optical Alignment Test Bed, 2019 Marshall University
Phase Retrieval Using A Genetic Algorithm On The Systematic Image-Based Optical Alignment Test Bed, Jaime R. Taylor
Dr. Jaime R. Taylor
NASA’s Marshall Space Flight Center’s Systematic Image-Based Optical Alignment (SIBOA) Testbed was developed to test phase retrieval algorithms and hardware techniques. Individuals working with the facility developed the idea of implementing phase retrieval by breaking the determination of the tip/tilt of each mirror apart from the piston motion (or translation) of each mirror. Presented in this report is an algorithm that determines the optimal phase correction associated only with the piston motion of the mirrors.
Kondo Signatures Of A Quantum Magnetic Impurity In Topological Superconductors, 2019 Shanghai Jiao Tong University
Kondo Signatures Of A Quantum Magnetic Impurity In Topological Superconductors, Rui Wang, Wei-Yi Su, Jian-Xin Zhu, Chin-Sen Ting, Hai Li, Changfeng Chen, Baigeng Wang, Xiaoqun Wang
Physics & Astronomy Faculty Publications
We study the Kondo physics of a quantum magnetic impurity in two-dimensional topological superconductors (TSCs), either intrinsic or induced on the surface of a bulk topological insulator, using a numerical renormalization group technique. We show that, despite sharing the p+ip pairing symmetry, intrinsic and extrinsic TSCs host different physical processes that produce distinct Kondo signatures. Extrinsic TSCs harbor an unusual screening mechanism involving both electron and orbital degrees of freedom that produces rich and prominent Kondo phenomena, especially an intriguing pseudospin Kondo singlet state in the superconducting gap and a spatially anisotropic spin correlation. In sharp contrast, intrinsic TSCs ...
Applications Of Information Theory In Solar And Space Physics, 2019 Andrews University
Applications Of Information Theory In Solar And Space Physics, Jay R. Johnson, Simon Wing
Characterizing and modeling processes at the sun and space plasma in our solar system are difficult because the underlying physics is often complex, nonlinear, and not well understood. The drivers of a system are often nonlinearly correlated with one another, which makes it a challenge to understand the relative effects caused by each driver. However, entropy-based information theory can be a valuable tool that can be used to determine the information flow among various parameters, causalities, untangle the drivers, and provide observational constraints that can help guide the development of the theories and physics-based models. We review two examples of ...
Viewing The Eclipse From 109,000 Feet And The Road To Get There, 2019 Metropolitan Community College
Viewing The Eclipse From 109,000 Feet And The Road To Get There, Kendra Sibbernsen, Michael Sibbernsen
Faculty Publications, Department of Physics and Astronomy
The NASA Nebraska High Altitude Ballooning Program was one of 55 teams across the nation to fly weather balloons within the August 21st Total Solar Eclipse and stream live video to the internet. On this day, the Nebraska team launched three high altitude balloons to take scientific measurements and take photos and video ofthe Moon's shadow falling on the Earth. These balloons included the NASA common video streaming payload as well as experiments from students at Metropolitan Community College and from faculty and students at Omaha Public Schools. The launches took place at the "Gem Over the Prairie" event ...
Exomol Line List - Xxxiv. A Rovibrational Line List For Phosphinidene (Ph) In Its X³Σ¯ And A¹Δ Electronic States, 2019 Old Dominion University
Exomol Line List - Xxxiv. A Rovibrational Line List For Phosphinidene (Ph) In Its X³Σ¯ And A¹Δ Electronic States, Jonathan Langleben, Jonathan Tennyson, Sergei N. Yurchenko, Peter Bernath
Chemistry & Biochemistry Faculty Publications
A rovibronic line list for the ground (X3Σ−) and first excited (a1Δ) states of phosphinidene, 31PH, is computed. The line list is designed for studies of exoplanetary and cool stellar atmospheres with temperatures up to 4000 K. A combination of empirical and ab initio data is used to produce the line list: potential energy curves (PECs) are fitted using experimental transition frequencies; these transitions are reproduced with a root mean square error of 0.01 cm−1. The nuclear Schrödinger equation is solved using these PECs plus Born–Oppenheimer and spin splitting correction terms. Line ...
Improving Photometry And Astrophotography By Eliminating Dark Frames And Flat Fields, 2019 University of New Hampshire, Durham
Improving Photometry And Astrophotography By Eliminating Dark Frames And Flat Fields, Tom C. Ireland
Honors Theses and Capstones
I report on the efforts to improve the dark frames and flat fielding procedure for the charged-coupled device (CCD) camera for the Celestron C14 telescope at the UNH observatory. Dark frames are images taken while the shutter of the camera is closed so that only electronic and dark noise and other internal inconsistencies are recorded. These are important because they allow astronomers to subtract out interference from dark current. Additionally, flat fields are images of the entire field of the telescope so that the brightness in the pixels of the telescope’s field of view is uniform. Flat fields are ...
Normalization Of Leadville Neutron Monitor To Climax Neutron Monitor, 2019 University of New Hampshire
Normalization Of Leadville Neutron Monitor To Climax Neutron Monitor, Brian J. O'Connor
Honors Theses and Capstones
No abstract provided.
Analysis Of Autoguiding For Exoplanet Transit Research At The Unh Observatory, 2019 University of New Hampshire
Analysis Of Autoguiding For Exoplanet Transit Research At The Unh Observatory, Anthony Cappuccio
Honors Theses and Capstones
This paper will discuss the proper calibration technique for an autoguider of a CCD camera and the results that follow from successful exoplanet transit observations. A brief background on exoplanets, the transit method, and the analysis of their parent stars through photometry will be examined. The results will be presented in a before and after framework that will visually represent the data improvements from autoguiding as graphical Light Curves (LC). The addition of being able to autoguide at the UNH observatory will work towards providing future students with the possibility of performing follow-up ground-based observations and archiving their work online ...
Unh Observatory Exoplanet Transit Depth Limit, 2019 University of New Hampshire, Durham
Unh Observatory Exoplanet Transit Depth Limit, Nicholas R. Larose
Honors Theses and Capstones
Using the University of New Hampshire Observatory, we performed multiple exoplanet transits observations on a variety of systems. Of these transits, those performed with ideal weather conditions were chosen to do extensive analysis on. The transit chosen for initial analysis was HAT-P-56b. We then used Z-Score values, along with the average mean and standard deviation collected from multiple transits to determine a minimum possible transit depth of 7.4 +/- 0.6 mmag. This value will allow UNH to access exoplanet transit observation and / or confirm potential exoplanets, thus making the UNH Observatory more research capable. A follow up threshold transit ...
Graphene Used As A Lateral Force Microscopy Calibration Material In The Low-Load Non-Linear Regime, 2018 University of Kentucky
Graphene Used As A Lateral Force Microscopy Calibration Material In The Low-Load Non-Linear Regime, Mathias J. Boland, Jacob L. Hempel, Armin Ansary, Mohsen Nasseri, Douglas R. Strachan
Physics and Astronomy Faculty Publications
A lateral force microscopy (LFM) calibration technique utilizing a random low-profile surface is proposed that is successfully employed in the low-load non-linear frictional regime using a single layer of graphene on a supporting oxide substrate. This calibration at low loads and on low friction surfaces like graphene has the benefit of helping to limit the wear of the LFM tip during the calibration procedure. Moreover, the low-profiles of the calibration surface characteristic of these layered 2D materials, on standard polished oxide substrates, result in a nearly constant frictional, adhesive, and elastic response as the tip slides over the surface, making ...
Observation Of High-Energy Gamma-Rays With The Calorimetric Electron Telescope (Calet) On-Board The International Space Station, 2018 Louisiana State University and Agricultural and Mechanical College
Observation Of High-Energy Gamma-Rays With The Calorimetric Electron Telescope (Calet) On-Board The International Space Station, Nicholas Wade Cannady
LSU Doctoral Dissertations
The CALorimetric Electron Telescope (CALET) is a multi-instrument high-energy astrophysics observatory deployed to the International Space Station (ISS) in August 2015. The primary instrument is the calorimeter (CAL), which is intended for measurement of the cosmic ray electron flux in the energy range 10 GeV - 20 TeV. The CAL is also sensitive to gamma-rays in the energy range 1 GeV - 10 TeV and protons and nuclei up to PeV energies. Also present on the CALET payload are an Advanced Stellar Compass (ASC) for the fine determination of the pointing direction and the CALET Gamma-ray Burst Monitor (CGBM) for the observation ...
Research In Optics For Gravitational Wave Detection, 2018 Embry-Riddle Aeronautical University
Research In Optics For Gravitational Wave Detection, Britney Biltz, Noura Ibrahim, Brennan Moore
Undergraduate Research Symposium - Prescott
B.Biltz uses a horizontal “Zollner style” pendulum to monitor changes in the local gravitational field. The pendulum is attracted to the moon and the Sun and so, as the Earth turns, the pendulum’s equilibrium point shifts within a 24-hour period. This is an experiment designed to test the limits of such a pendulum. This sort of system may be useful as a method of monitoring and correcting for gravity gradient noise in future gravitational wave detectors.
N.Ibrahim characterizes thermo-optic noise in high-performance mirror coatings of the type used in Advanced LIGO. To characterize thermo-optic noise, she measures ...
The Periglacial Landscape Of Mars: Insight Into The 'Decameter-Scale Rimmed Depressions' In Utopia Planitia, 2018 The University of Western Ontario
The Periglacial Landscape Of Mars: Insight Into The 'Decameter-Scale Rimmed Depressions' In Utopia Planitia, Arya Bina
Electronic Thesis and Dissertation Repository
Currently, Mars appears to be in a ‘frozen’ and ‘dry’ state, with the clear majority of the planet’s surface maintaining year-round sub-zero temperatures. However, the discovery of features consistent with landforms found in periglacial environments on Earth, suggests a climate history for Mars that may have involved freeze and thaw cycles. Such landforms include hummocky, polygonised, scalloped, and pitted terrains, as well as ice-rich deposits and gullies, along the mid- to high-latitude bands, typically with no lower than 20o N/S. The detection of near-surface and surface ice via the Phoenix lander, excavation of ice via recent impact cratering ...
High Dynamic Range Optical Devices And Applications., 2018 University of Louisville
High Dynamic Range Optical Devices And Applications., Elijah Robert Jensen
Electronic Theses and Dissertations
Much of what we know about fundamental physical law and the universe derives from observations and measurements using optical methods. The passive use of the electromagnetic spectrum can be the best way of studying physical phenomenon in general with minimal disturbance of the system in the process. While for many applications ambient visible light is sufficient, light outside of the visible range may convey more information. The signals of interest are also often a small fraction of the background, and their changes occur on time scales so quickly that they are visually imperceptible. This thesis reports techniques and technologies developed ...
Automation And Enhancements To The Erau Oscom System Space Situational Awareness, 2018 Embry-Riddle Aeronautical University
Automation And Enhancements To The Erau Oscom System Space Situational Awareness, Sergei Bilardi, Patrick Rupp, Yevgeniy Lischuk, Joseph Stroup
Beyond: Undergraduate Research Journal
OSCOM, Optical tracking and Spectral characterization of CubeSats for Operational Missions, is a system developed at Embry-Riddle Aeronautical University to produce time-resolved photometry of small satellites using commercial-off-the-shelf hardware. OSCOM has been able to observe resident space objects (RSOs) as small as CubeSats using a Celestron 11” RASA and a CMOS machine vision camera from Allied Vision. By obtaining photometric measurements of satellites, a light curve can be constructed and used to help determine satellite characteristics such as spin rate, satellite state, and even satellite attitude. To enhance the OSCOM system’s ability to observe small satellites, there is ongoing ...
Spectral Mixture Modeling Using Principle Component Analysis, 2018 Olivet Nazarene University
Spectral Mixture Modeling Using Principle Component Analysis, Joseph S. Makarewicz, Heather D. Makarewicz
Scholar Week 2016 - present
A method for modeling mixtures between two end-member spectra using principle component analysis and linear regression was presented. The presentation included results from three binary mixture data sets including orthopyroxene-clinopyroxene, kaolinite-montmorillonite, and nontronite-ferrihydrite.
Design And Evaluation Of 3d-Printed Filar Micrometer, 2018 Olivet Nazarene University
Design And Evaluation Of 3d-Printed Filar Micrometer, Emily Rull
Scholar Week 2016 - present
This project sought to design and 3D-print a filar micrometer for double star measurements that amateur astronomers could produce cost effectively.
Double stars are celestial objects that allow the mass of stars to be calculated by assessing their orbits. Stellar mass affects every current model of stellar evolution, but the most accurate double star orbits can take decades to record. As a result of the long-term nature of such observations and lack of groundbreaking research in double star studies, professional astronomers are no longer focused on making these measurements. This allows amateur astronomers to pick up where professionals have left ...