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On The Orbital Dynamics Of Exoplanets, Exomoons, And Submoons, Shaan Dharmesh Patel 2025 University of Texas at Arlington

On The Orbital Dynamics Of Exoplanets, Exomoons, And Submoons, Shaan Dharmesh Patel

Physics Dissertations - Archive

Although exoplanet detection has long been a central focus in astronomy, growing interest in exomoons has highlighted the increasing need for theoretical frameworks to interpret emerging candidates. Furthermore, while submoons, natural satellites orbiting moons, are not presently observed in the Solar System and remain speculative (e.g., the hypothesized past submoon of Saturn’s Iapetus), their existence is plausible within the context of the complex and diverse architectures now identified across planetary and stellar systems. We develop a generalized framework to assess the orbital stability of exomoons and submoons through comprehensive N-body simulations incorporating both three-body dynamics and tidal interactions, with the …


Archival Stellar Flare Follow-Up In Evryscope Observations, Tyler J. Thomas 2025 University of Central Florida

Archival Stellar Flare Follow-Up In Evryscope Observations, Tyler J. Thomas

Honors Undergraduate Theses

M dwarfs, the most abundant stars in the galaxy, are prime targets in the search for habitable exoplanets. However, their high flare activity may compromise planetary atmospheres, with Coronal Mass Ejections (CMEs) increasing this risk. Despite this, the relationship between M dwarf flares and CMEs is not well understood. This study uses archival data from Evryscope North and South, crossmatched with Sloan Digital Sky Survey (SDSS) and Gaia data, to investigate this relationship. This crossmatching demonstrated an abundance of stars within the 20 arcsecond Evryscope uncertainty. The analysis also revealed a modest excess of K1 and F9 type stars but …


Classification Of Variable Stars Using Convolutional Neural Network, Abhina Premachandran Bindu 2025 CUNY City College

Classification Of Variable Stars Using Convolutional Neural Network, Abhina Premachandran Bindu

Dissertations and Theses

This research focuses on developing Convolutional Neural Networks (CNNs), for the process of classifying and identifying variable stars through the analysis of unprocessed light curves from Transiting Exoplanet Survey Satellite (TESS). As astronomical data is becoming increasingly complex, and as advanced missions deploy sophisticated instruments for data collection, both the quality and quantity of the data are improving at a rapid pace. This has created an urgent need to automate the analysis process using efficient and effective methods, such as those based on machine learning. While previous research has explored machine learning approaches, there has been limited focus on implementing …


F-Layer Parameters Derived By Airglow Emissions At Pituffik Sb, Greenland, Jessica Norrell, Ivana Molina, Michael Negale, Jeffrey Holmes 2025 Utah State University Space Dynamics Laboratory

F-Layer Parameters Derived By Airglow Emissions At Pituffik Sb, Greenland, Jessica Norrell, Ivana Molina, Michael Negale, Jeffrey Holmes

Space Dynamics Laboratory Publications

Atomic oxygen airglow has long been used as tracer for the peak height and electron density of the F-layer (e.g. Sahai et al., 1981). Tinsley and Bittencourt (1975) described a method by which OI airglow is used to determine F-layer parameters. They found that the square root of the column emission rate of an optically thin layer created by radiative recombination emission was proportional to the peak electron density of the F-layer.

An all-sky imager (ASI) was recently installed at Pituffik, Greenland (76.51˚N, 68.74˚W), with four filters relevant to this study: 5725, 6300, 7715 and 7774 Å. We have used …


Structural Design & Analysis, Poti G. Doukas 2025 UNP EAT

Structural Design & Analysis, Poti G. Doukas

Space Dynamics Laboratory Publications

Agenda

  • Structural Requirements
  • Deployers
  • Engineering Drawings
  • Verification Testing


Software Management, Space Dynamics Laboratory 2025 Utah State University

Software Management, Space Dynamics Laboratory

Space Dynamics Laboratory Publications

Agenda

  1. Software Organization Methods
  2. Example Software Workflow
  3. Small Sat Specific Tips


Requirements And C&Dh Design, Space Dynamics Laboratory 2025 Utah State University

Requirements And C&Dh Design, Space Dynamics Laboratory

Space Dynamics Laboratory Publications

  • What is it?
  • Processor Selection
  • CDH Hardware
  • OS Selection
  • Memory - Radiation
  • Memory - Radiation Mitigation
  • Memory - Partitions
  • Memory - File System
  • System Startup
  • Startup Stages
  • Software Start-up
  • Serial Protocol
  • I2C / One Wire Communication Tips
  • Fault Handling: Watchdog Timer
  • CDH Watchdog (Simple)
  • CDH Watchdog (Use Case)
  • Watchdog Timer Tips
  • Synchronizing and Managing Time


Radiation Hardness Drivers For Mission Success – What We Have Learned, Space Dynamics Laboratory 2025 Utah State University

Radiation Hardness Drivers For Mission Success – What We Have Learned, Space Dynamics Laboratory

Space Dynamics Laboratory Publications

RHA consists of all activities undertaken to ensure that the electronics and materials of a space system perform to their design specifications throughout exposure to the mission space environment


Smallsat Pcb Engineering, Space Dynamics Laboratory 2025 Utah State University

Smallsat Pcb Engineering, Space Dynamics Laboratory

Space Dynamics Laboratory Publications

  • Concept
  • Design
  • Build
  • Lessons Learned


Communications (Comm) Subsystem: Smallsat Antennas, Jim White 2025 Colorado Satellite Services

Communications (Comm) Subsystem: Smallsat Antennas, Jim White

Space Dynamics Laboratory Publications

  • A Practical Approach to SmallSat and Cubesat Antennas
  • Antennas Designed Using Requirements
  • Antenna Requirements
  • Systems Engineering is Required
  • What is a Radio Wave?
  • What is an Antenna?
  • Best Practices
  • Testing
  • Summary


The Presence Of Outer Giant Planets And Their Role In Inner Planet Formation With And Without Their Influence, Mateo E. Guerra Toro 2025 Missouri State University

The Presence Of Outer Giant Planets And Their Role In Inner Planet Formation With And Without Their Influence, Mateo E. Guerra Toro

Graduate Theses/Dissertations

We performed dynamical simulations of the giant impact phase of planet formation to investigate the formation of inner terrestrial planets under the influence of 4 solar system-like outer giant planets. We developed a new code using the N-body simulation suite REBOUND and REBOUNDx (Rein et al. (2019) and Tamayo et al. (2019)) to simulate 2 stages of planetary formation: a residual gaseous protoplanetary disk phase and subsequent dynamical evolution after the disk photoevaporates. The initial conditions for the inner planetary embryos were taken by Morrison et al. (2020) based on a range of solid surface densities that produced Super-Earth terrestrial …


Range Safety And Design For Launch, Space Dynamics Laboratory 2025 Utah State University

Range Safety And Design For Launch, Space Dynamics Laboratory

Space Dynamics Laboratory Publications

Design to make licensing and launch easy

  • Sometimes the most innovative or elegant solution isn’t the best one
  • The less you have to prove, the better
  • Don’t use novel materials
  • Don’t use novel methods

Example: 3D printing is cool and reduces part count because you can design otherwise unmachinable parts

  • Now you have to test, analyze, and prove to everyone that your part won’t fail
  • If you machined the parts from AL 6061-T6 and bolted them together with stainless steel fasteners, nobody would have looked twice


A Compact Frequency Comb Generator For Large-Format Superconducting Microwave Kinetic Inductance Detectors, Sungyoun Seo 2025 University of Rhode Island

A Compact Frequency Comb Generator For Large-Format Superconducting Microwave Kinetic Inductance Detectors, Sungyoun Seo

Open Access Master's Theses

Microwave Kinetic Inductance Detectors (MKIDs) are promising superconducting detectors that achieve superior sensitivity to silicon-based photo detectors by leveraging a small bandgap of superconductors. They are advantageous for sensitive imaging instruments, particularly space telescopes. However, a large-format array with several hundreds of thousands of detectors is required for large-scale observations in space, and it encounters multiple challenges. The biggest challenge is the absence of compact, energy-efficient, and radiation-tolerant readout solutions. Of multiple functions in the MKID readout, the new frequency comb generator is presented in this thesis. It features a low on-chip memory requirement while promising the relaxed frequency resolution …


Pulse-Profile Modeling And Spin–Orbit Alignment In A Suzaku Sample Of Accreting X-Ray Binary Pulsars, Silas G.T. Laycock, Rigel C. Cappallo, Pragati Pradhan, Dimitris M. Christodoulou, Biswajit Paul 2025 Embry-Riddle Aeronautical University

Pulse-Profile Modeling And Spin–Orbit Alignment In A Suzaku Sample Of Accreting X-Ray Binary Pulsars, Silas G.T. Laycock, Rigel C. Cappallo, Pragati Pradhan, Dimitris M. Christodoulou, Biswajit Paul

Publications

We report pulse-profile modeling of a sample of 23 X-ray binary pulsars observed with the Suzaku X-ray satellite. These pulsars have spin periods ranging from 0.7 to 9400 s, and their X-ray emission is powered by the accretion from their stellar companions. We fitted each individual pulse profile with the Polestar geometric model, which accounts for X-ray emission from two hot spots modeled as a simple combination of fan+pencil beam components, including an approximation for gravitational light bending. In 14 of 21 cases, our measurements of the inclinations of the pulsar spin axes broadly agree with the corresponding inclinations of …


Unraveling Visible Spectra Of S-Type Stars: The F3Δ–A3Δ (Α System) And E3Π–A3Δ (Β System) Band Systems Of Zro, Manish Bhusal, Peter Bernath, Jacques Liévin 2025 Old Dominion University

Unraveling Visible Spectra Of S-Type Stars: The F3Δ–A3Δ (Α System) And E3Π–A3Δ (Β System) Band Systems Of Zro, Manish Bhusal, Peter Bernath, Jacques Liévin

Chemistry & Biochemistry Faculty Publications

ZrO has many low-lying states, and its spectra are essential for the characterization of S-type stars. A high-resolution emission spectrum recorded with a Fourier transform spectrometer at the National Solar Observatory is used for the analysis. The 0–0 and 1–0 bands of the f³Δ-a³Δ system (α system) and the 0–0 band of the e³Π-a³Δ system (β system) have been rotationally analyzed using the modern spectral fitting program PGOPHER. New ab initio calculations of transition dipole moments have been performed to determine the band strengths. These band strengths are used to produce line lists that are suitable for the …


M Star Opacities: The B³Π–X³Δ Band System Of Tio, Peter F. Bernath, Manish Bhusal, Mirek R. Schmidt 2025 Old Dominion University

M Star Opacities: The B³Π–X³Δ Band System Of Tio, Peter F. Bernath, Manish Bhusal, Mirek R. Schmidt

Chemistry & Biochemistry Faculty Publications

The spectra of titanium monoxide (TiO) are used to classify M stars. TiO experimental cross sections based on a high-resolution emission spectrum recorded with a Fourier transform spectrometer at the National Solar Observatory are used for the analysis of the TiO B³Π–X³Δ transition (𝛾' system). The 3–2 and 4–3 vibrational bands are analyzed for the first time, and the analysis of the 2–1 band is revised. The transition dipole moment function from an ab initio calculation is used to calculate the band strengths. These band strengths are used to produce a B³Π–X³Δ line list for the vibrational levels v' ⩽ …


Precision Measurement Of The Muon’ S Anomalous Precession Frequency Using Energy Integrated Analysis In The Fermilab Muon G- 2 Experiment, Joseph Peck 2025 University of Kentucky

Precision Measurement Of The Muon’ S Anomalous Precession Frequency Using Energy Integrated Analysis In The Fermilab Muon G- 2 Experiment, Joseph Peck

Theses and Dissertations--Physics and Astronomy

This dissertation investigates the anomalous magnetic moment of the muon, aµ, through the Fermilab Muon g -2 Experiment, which aims to measure aµ to a precision of about 140 parts-per-billion.

Muons were injected into a magnetic storage ring where their decay positrons were detected by calorimeters. The changing spin and momentum orientation leads to an oscillation in decay positron counts, known as the anomalous precession frequency ! a. Using the magnetic field and !a measurements, we can determine the value of a µ. This study focuses on the Q-Method determination of !a, which utilizes an energyintegrated reconstruction rather than high-energy …


A Multidisciplinary Approach To The Thermal And Non-Thermal Mechanisms In Galaxy Clusters, Sheng-Chieh Lin 2025 University of Kentucky

A Multidisciplinary Approach To The Thermal And Non-Thermal Mechanisms In Galaxy Clusters, Sheng-Chieh Lin

Theses and Dissertations--Physics and Astronomy

Galaxy clusters form at the intersections of the cosmic web and carry imprints of the structure formation history of the universe. As massive, multi-component systems, they offer unique insights into the astrophysical processes that govern both structure formation and galaxy evolution. Observable across the full electromagnetic spectrum, clusters emit photons through a variety of mechanisms, each tracing different physical processes. This dissertation investigates both the thermodynamic and non-thermal properties of the intracluster medium (ICM) to better understand the physical processes shaping observed phenomena. It comprises three main studies, each targeting a different aspect of galaxy cluster physics. In the second …


From Poetry To Policy: How H-Stem Has Guided My Research Path, Kayla D. Taylor 2025 Embry-Riddle Aeronautical University

From Poetry To Policy: How H-Stem Has Guided My Research Path, Kayla D. Taylor

Student Works

Embry-Riddle PhD student Kayla Taylor was invited to share how Humanistic STEM has shaped her educational journey at the third annual Humanistic STEM symposium.


Reconnection-Driven Electron Acceleration, Ripudaman Singh Nirwan 2025 West Virginia University

Reconnection-Driven Electron Acceleration, Ripudaman Singh Nirwan

Graduate Theses, Dissertations, and Problem Reports (ETD)

Magnetic reconnection converts the magnetic energy available in a plasma to the kinetic energy of its constituent particles. In the simplest case, it occurs between anti-parallel magnetic field lines meeting in a plane. Another variant known as ‘component reconnection’ involves field lines reconnecting at an angle, giving a non-zero magnetic field component perpendicular to the plane of reconnection. This component is known as the ‘guide field’ and it is normalized to the reconnecting field in the literature. The guide field controls the particle-scale dynamics of reconnection and influences the ensuing particle acceleration.

Component reconnection occurs in the Earth’s magnetosphere, along …


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