Astrophysics and Astronomy Commons^™

Temperature Predictions With Zncuins/Zns Quantum Dots, Reu/Fri Program Physics And Astronomy, Amber Banks

Student Works

For hundreds of years, humans have built thermometers based on the principles of thermal expansion and contraction. In the modern world, there is a need to scale down our thermometers to monitor cellular reactions, both within the human body and within artificial organ chips. Lewis et al. (2020) introduces a nanoscale thermometer based on the thermal expansion of CdTe quantum dots. When ex panded, these dots exhibit systematic changes in photoluminescence (PL) which are recognized by a neural network as an increase in temperature. Our research builds upon the framework of Lewis et al. (2020), testing its feasibility with ZnCuInS/ZnS …

Quantum Error Correction: Studying Correlated Errors On Surface Codes, Reu/Fri Program Physics And Astronomy, Pritesh Thakur

Student Works

No abstract provided.

The Atmospheric Characterization Of Abnormally Blue Early T-Dwarfs Midterm Presentation, Reu/Fri Program Physics And Astronomy, Madalyn Chapleski

Student Works

No abstract provided.

Tabletop Isotropic Source For Neutron Science Training Poster, Reu/Fri Program Physics And Astronomy, Jarom Peterson

Student Works

To develop affordable tabletop neutron sources for neutron science research and education, GS20 scintillator glass doped with Americium-241 is being evaluated inside the BYU Isotropic Fission Chamber (IFC). Our 1985 sample was assessed for radiation damage and found to be in good condition. Neutrons from Am-241 interactions were optically flagged and observed using the IFC in conjunction with the LGB-PVT Neutron Pseudo Spectrometer Detector. Data was recorded via a CAEN desktop digitizer. The analysis code continues to be developed, and the neutron detector will be calibrated using deuterium-deuterium (DD) interactions in the future.

Quantum Ai To Factor Intergers Midterm Presentation, Reu/Fri Program Physics And Astronomy, Kai Sandberg

Student Works

No abstract provided.

Using Novel Technology And Sensemaking In The Classroom, Reu/Fri Program Physics And Astronomy, Julio Escobedo

Student Works

This project looked into the usefulness of various new and unique technologies in a science classroom setting to allow for more sensemaking to occur among students. This was done through professional developments or training for multiple educators on how to use these devices in the classrooms. We found that each new technology had a unique set of useful capabilities and drawbacks. These findings suggest that implementation of these technologies can increase sensemaking if done properly and with proper training beforehand.

From The University To The Universe: Byu’S West Mountain Observatory, Amber Zendejas, Dan Broadbent

BYU West Mountain Observatory Project

Brigham Young University’s West Mountain Observatory (WMO) is a research facility that offers primarily undergraduate students valuable mentoring and hands-on learning opportunities. Established in 1981, the observatory was built in response to increasing light pollution in Provo, Utah, which began affecting research at the Orson Pratt Observatory (OPO) atop the Eyring Science Center on the BYU main campus. Before WMO was created, OPO served as the primary observatory for astronomical research at BYU. Construction plans for a new observatory began in the late 1970s, as university planners and astronomers sought a location with minimal light pollution, favorable elevation, relatively easy …

From The University To The Universe: A Scientific And Historical Overview Of The West Mountain Observatory, Amber Zendejas, Dan Broadbent

BYU West Mountain Observatory Project

BACKGROUND

• November 1980 - Construction began on the observatory’s main building

• 1981 - Observations begin, away from Provo’s Light Pollution

• Located on West Mountain, west of Spanish Fork, UT

Stability Of Metal Fluoride Films When Irradiated With Electron Beam, Devin M. Lewis, Waseem Ashraf

Student Works

LiF is an essential mirror coating for the upcoming LUVOIR space telescope. In order to improve the technology readiness level of this material a study was to be conducted, observing the surface changes of LiF thin films as exposed to humidity for extended periods of time. However, initial attempts to characterize the film with SEM showed that LiF is unstable under all electron beam parameters experimented with. This creates the concern that LiF is also sensitive to other forms of radiation damage. Further investigation may suggest the need to transition to another mirror coating that is more resilient to radiation …

Cooperative Observing At A Modest-Sized Observatory, Michael D. Joner, Denzil E. Watts Iv, Seneca H. Bahr, Oliver Hancock, Michael W. Holland, Hafsa Jamil, Eden Saxton, Malaya Williams-Jones

BYU West Mountain Observatory Project

The West Mountain Observatory is an astronomical research facility operated by Brigham Young University, located on an isolated mountain approximately 22 kilometers southwest of the main Provo UT campus. The observatory was upgraded 15 years ago and has since been utilized primarily as an undergraduate research facility. The observatory is well suited to do work on projects utilizing time series photometric observations and has been particularly successful at conducting multiple projects for undergraduate student researchers that require observations of different durations and cadences using various filter combinations. This requires additional planning and cooperation between the different programs that are often …

Order And Harmony: Kepler’S Guiding Forces, Dan Broadbent

Faculty Publications

Adapted from the article “Order and Harmony: Kepler’s Guiding Forces” included in “Towards Mysteries of the Cosmos with Johannes Kepler – on the 450th Anniversary of His Birth,” a commemorative volume published by the Obserwatorium Atronommiczne Krolowej Jadwigi Rzepienniku Biskupim (Queen Jadwiga Observatory of Rzepiennik Biskupi Poland) December 2021. Adapted with permission.

As the subject librarian for physics and astronomy at Brigham Young University, the author has had the privilege of handling some of Johannes Kepler’s original books preserved in the university’s archives. One of the most impressive materials in the archive is a large page from Mysterium Cosmographicum that …

Light And Truth: Measuring Unseen Harm In Individuals And Communities, Hannah Pfost

Undergraduate Honors Theses

While the fields of physics and international development may seem disparate, the insights gained from studying each one of them can improve understanding of the other. Here, I demonstrate that concept as applied to computational optics and historical memory. Thus, the purpose of this project is threefold: (1) to computationally model light transport through tissue, and use that model to inform choices about a physical system; (2) to determine the types of historical memory recommended in the final reports of truth commissions; and (3) to give evidence for the usefulness of human-centered design in both areas. To model light transport, …

Computational Development Of A Miniature Quantum Dot Spectrometer For Use In Space, Joseph Richardson

Undergraduate Honors Theses

Miniature spectrometers are of great interest to NASA as necessary instrumentation is scaled down and optimized for specific space application. Semiconductor nanocrystals called quantum dots (QD) are being used to create a miniature high-resolution filter-based spectrometer, with the goal of use in space within 5 years. Computational imaging techniques— such as automated image analysis and mathematical spectrum reconstruction algorithms—are key to making the QD spectrometer a reality. This thesis will discuss the process of developing these computational methods, along with the improvements that have occurred from previous work.

Historical Milestones In Astronomy: As Shown Through The Byu Special Collections Archives, Dan Broadbent

Faculty Publications

Science Research: The “Long Conversation”

• Ideas in science can take a long time to develop.
• How do they develop?

• These books document a part of a conversation that began 447 years ago and spanned a 153 year period… documenting:
• how the overall nature of the universe was worked out,
• the establishment of the scientific method, and the boundaries of religious authority,
• and culminated in Isaac Newton’s book that presented his three laws of motion that allow us to explore the universe to this day.

Byu’S Connection To The Development Of Optical Memory: Innovation Takes Multiple Disciplines, Dan Broadbent

Faculty Publications

Optical memory technology is a way to store information using lasers and is used in videodiscs, CDs, DVDs, Blu-rays, M-Discs, etc. This technology was developed in Torrance, California in the 1970s by a team lead by Kent D. Broadbent, who graduated from BYU with a degree in Physics in 1949.

This display showcases the technology and those involved in its development.

Emergent Properties Of The Transport Of Sand, Eric Lenhart

Undergraduate Honors Theses

In the interest of drawing conclusions about Aeolian environments based on remote imaging, we investigated how air flow forms self-organizing patterns, such as ripples, across loose particulate surfaces. Specifically, we analyzed various models of sand transport, particularly Nishimori’s model, to note the effects of altering various parameters, including wind direction, saltation length, diffusion, and a saltation proportionality constant. As a measure of the frustration of the emergent patterns, Y-junctions were counted at various values of the parameters. A strong correlation with the saltation proportionality constant and no correlation with the saltation height were found. As an additional use of the …

Using Coherence To Improve The Calculation Of Active Acoustic Intensity With The Phase And Amplitude Gradient Estimator Method, Mylan Ray Cook

Theses and Dissertations

Coherence, which gives the similarity of signals received at two microphone locations, can be a powerful tool for calculating acoustic quantities, particularly active acoustic intensity. To calculate active acoustic intensity, a multi-microphone probe is often used, and therefore coherence between all microphone pairs on the probe can be obtained. The phase and amplitude gradient estimator (PAGE) method can be used to calculate intensity, and is well suited for many situations. There are limitations to this method—such as multiple sources or contaminating noise in the sound field—which can cause significant error. When there are multiple sources or contaminating noise present, the …

Writing And Designing A Chapter On Mercury And Pluto For The Textbook Exploring The Planets (Explanet.Info), Braxton Clark Spilker

Theses and Dissertations

Exploring the Planets (http://explanet.info) is a free online college textbook covering thebasic concepts of planetary science emphasizing the character and evolution of the planetarybodies in the Solar System. The latest edition (3rd edition) was published online in 2007 by EricH Christiansen. Since the release of the third edition, two important planetary missions havebeen completed: MESSENGER (to Mercury) and New Horizons (to Pluto). These missionsprovided new information and fundamental insights into these planetary bodies, which have notyet been included in Exploring the Planets. The modern results based on recent investigations ofMercury and Pluto are critical for our understanding of the nature …

Fitting Parameter Uncertainties In Least Squares Fitting, R. Steven Turley

Faculty Publications

This article review the theory and practice of computing uncertainties in the fit parameters in least squares fits. It shows how to estimate the uncertainties and gives some numerical examples in Julia of their use. Examples are given and validated for both linear and nonlinear fits.

Polynomial Fitting, R. Steven Turley

Faculty Publications

This article reviews the theory and some good practice for fitting polynomials to data. I show by theory and example why fitting using a basis of orthogonal polynomials rather than monomials is desirable. I also show how to scale the independent variable for a more stable fit. I also demonstrate how to compute the uncertainty in the fit parameters. Finally, I discuss regression analysis: how to determine whether adding an additional term to the fit is justified.

Ion Friction At Small Values Of The Coulomb Logarithm, Robert Tucker Sprenkle

Theses and Dissertations

We create a dual-species ultracold neutral plasma (UNP) by photo-ionizing Yb and Ca atoms in a dual-species magneto-optical trap. Unlike single-species UNP expansion, these plasmas are well outside of the collisionless (Vlasov) approximation. We observe the mutual interaction of the Yb and Ca ions by measuring the velocity distribution for each ion species separately. We model the expansion using a fluid code including ion-ion friction and compare with experimental results to obtain a value of the Coulomb logarithm of Λ= 0.04.

Use Of Phase And Amplitude Gradient Estimation For Acoustic Source Characterization And Localization, Joseph Scott Lawrence

Theses and Dissertations

Energy-based acoustic quantities provide vital information about acoustic fields and the characterization of acoustic sources. Recently, the phase and amplitude gradient estimator (PAGE) method has been developed to reduce error and extend bandwidth of energy-based quantity estimates. To inform uses and applications of the method, analytical and experimental characterizations of the method are presented. Analytical PAGE method bias errors are compared with those of traditional estimation for two- and three-microphone one-dimensional probes. For a monopole field when phase unwrapping is possible, zero bias error is achieved for active intensity using three-microphone PAGE and for specific acoustic impedance using two-microphone PAGE. …

Thin Film Carbon Nanofuses For Permanent Data Storage, Kevin Robert Laughlin

Theses and Dissertations

We have fabricated nanofuses from thin-film, arc-evaporation carbon for use in permanent data storage. Thin film carbon fuses have fewer fabrication barriers and retain the required resistivity and structural stability to work as a data storage medium. Carbon thin films were characterized for their electrical, microstructural, and chemical bonding properties. Annealing the thin-film carbon in an argon environment at 400°C reduced the resistivity from about 4*10^-2 Ω cm as deposited down to about 5*10^-4 Ω cm, allowing a lower blowing voltage. Nanofuses with widths ranging from 200 nm down to 60 nm were fabricated and tested. They blow …

Development Of A Real-Time Auralization System For Assessment Of Vocal Effort In Virtual-Acoustic Environments, Jennifer Kay Whiting

Theses and Dissertations

This thesis describes the development of the real-time convolution system (RTCS) for a little-studied talker/listener in virtual acoustic environments. We include descriptions of the high-resolution directivity measurements of human speech, the RTCS system components, the measurement and characterization of oral-binaural room impulse responses (OBRIRs) for a variety of acoustic environments, and the compensation filter necessary for its validity. In addition to incorporating the high-resolution directivity measurements, this RTCS improved on that developed by Cabrera et al. [1] through the derivation and inclusion of the compensation filter. Objective measures in the time- and frequency-domains, as well as subjective measures, were developed …

Evaporated Aluminum Fluoride As A Barrier Layer To Retard Oxidation Of Aluminum Mirrors, Margaret Miles

Theses and Dissertations

The aluminum oxide growth rate for aluminum protected with 2.4 nm of aluminum fluoride has been determined. We show that a 2.4 nm aluminum fluoride layer does not prevent aluminum from oxidation but does significantly retard the oxide growth – decreasing the oxide layer thickness from 1 nm in less than an hour to 0.9 nm over 116 hours. Additionally, the optical constants for aluminum oxide growing under an aluminum fluoride barrier layer have been determined – showing an increase in absorption at high energies for Al₂O₃ forming at room temperature as compared to highly ordered Al …

The Morphology And Uniformity Of Circumstellar Oh/H2O Masers Around Oh/Ir Stars, Derek Sean Felli

Theses and Dissertations

Even though low mass stars (< 8 solar masses) vastly outnumber high mass stars (< 8 solar masses), the more massive stars drive the chemical evolution of galaxies from which the next generation of stars and planets can form. Understanding mass loss of asymptotic giant branch stars contributes to our understanding of the chemical evolution of the galaxy, stellar populations, and star formation history. Stars with mass < 8 solar masses form planetary nebulae, while those with mass < 8 solar masses go supernova. In both cases, these stars enrich their environments with elements heavier than simple hydrogen and helium molecules. While some general info about how stars die and form planetary nebulae are known, specific details are missing due to a lack of high-resolution observations and analysis of the intermediate stages. For example, we know that mass loss in stars creates morphologically diverse planetary nebulae, but we do not know the uniformity of these processes, and therefore lack detailed models to better predict how spherically symmetric stars form asymmetric nebulae. We have selected a specific group of late-stage stars and observed them at different scales to reveal the uniformity of mass loss through different layers close to the star. This includes observing nearby masers that trace the molecular shell structure around these stars. This study revealed detailed structure that was analyzed for uniformity to place constraints on how the mass loss processes behave in models. These results will feed into our ability to create more detailed models to better predict the chemical evolution of the next generation of stars and planets.

Machine Learning To Discover And Optimize Materials, Conrad Waldhar Rosenbrock

Theses and Dissertations

For centuries, scientists have dreamed of creating materials by design. Rather than discovery by accident, bespoke materials could be tailored to fulfill specific technological needs. Quantum theory and computational methods are essentially equal to the task, and computational power is the new bottleneck. Machine learning has the potential to solve that problem by approximating material behavior at multiple length scales. A full end-to-end solution must allow us to approximate the quantum mechanics, microstructure and engineering tasks well enough to be predictive in the real world. In this dissertation, I present algorithms and methodology to address some of these problems at …

Oxidization Of Al And A-Si As A Protective Layer, Yhoshua Wug

Student Works

Arguably, the best chance to produce a IR-optical-UV-EUV mirror for a future space observatory is a multilayer mirror coated by a thin bare aluminum layer. Using an Al layer presents challenges that have to be overcome first. Al oxidizes rapidly as soon as it comes in contact with the atmosphere. One solution is to block the oxidation of Al by covering the mirror with a protective layer and remove it once the mirror is in space. freshly, deposited a-Si would be a good candidate for protecting the mirror. Removing it in space also presents some challenges. The best way to …

Observing Kelt Candidate Objects In The Search For Transiting Exoplanets, Maria Martinez

Student Works

The main goal of this project was to learn how to participate and be a part of a real observational team. We worked with the KELT exoplanet search project. While working with the KELT project we hoped to be able to confirm a candidate object as a planet. However, trying to discover a transiting planet was not our main goal for the summer. In addition, we also set out to learn how to work in an observatory, operate telescopes, and process data. The different objects we observed throughout the summer were not all determined to be transiting exoplanets, but we …

Developing Instrumentation For Fabricating And Characterizing Thin Film Aluminum Mirrors, P. Claire Segura

Student Works

The best material for constructing a mirror for a broad-bandwidth telescope that is also capable of reflecting EUV light is pure aluminum. In order to test how the reflectance of aluminum in the EUV range changes as it oxidizes, a system has been constructed that allows a thin aluminum mirror to be constructed inside of a vacuum, where its reflectance can then be tested immediately. Because the experiment must take place in a vacuum, it must also be controlled remotely through a computer program, which manages the mirror fabrication process as well as the collection and analysis of reflectance data. …