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To The Moon And Mars And Back To The Archives: Working With Modern Space Collections At The University Of Arizona Libraries, Molly Stothert-Maurer, Lisa E. Duncan 2022 Arizona State Museum

To The Moon And Mars And Back To The Archives: Working With Modern Space Collections At The University Of Arizona Libraries, Molly Stothert-Maurer, Lisa E. Duncan

Journal of Western Archives

With a long history at the University of Arizona with excellence in the lunar and planetary sciences, the University of Arizona Libraries Special Collections has increased its collecting of the History of Science and Technology. These large, modern space collections pose unique challenges and require specific needs to be addressed in order for the collections to be stored, processed and made available for access. It is essential for archivists working with these collections to ask their donors the right questions and learn the limitations and restrictions that often come with acquiring modern space collections. Archives around the country have started ...


Twisting Lasers With The Faraday Effect, Harrison Werrell 2022 Macalester College

Twisting Lasers With The Faraday Effect, Harrison Werrell

Macalester Journal of Physics and Astronomy

Our objective with this project was to create a system and procedure to quantify the magnetization of a material with polarized light by using the Faraday Effect, where the light is rotated according to the magnetization. This type of system has seen use in technologies such as magneto-optical drives and optical isolators, and is part of the study of optical materials, along with the similar MagnetoOptical Kerr Effect. Our system, specifically, is intended to be used as part of an advanced Physics Lab in the future. It uses an electromagnet to magnetize a sample, and a laser to observe the ...


Electrical Analysis Of A Pem Electrolysis Cell, Joey Wehrley, James Doyle 2022 Macalester College

Electrical Analysis Of A Pem Electrolysis Cell, Joey Wehrley, James Doyle

Macalester Journal of Physics and Astronomy

Polymer Electrolyte Membrane (PEM) electrolysis is a form of electrolysis that is heavily used in commercial capacities. It functions by using a membrane and an electric charge in order to perform electrolysis water, splitting it into its component parts - Hydrogen and Oxygen. These parts can then be used in a number of different applications, including reversing the electrolysis process to regenerate some energy in the form of electricity. During this experiment, multiple currents were run through a PEM cell, and voltages across the membrane were measured. It was found that a standard R/C charging model can be fit to ...


Neutrino Oscillations In The Presence Of A Magnetic Field, Chinhsan Sieng 2022 Macalester College

Neutrino Oscillations In The Presence Of A Magnetic Field, Chinhsan Sieng

Macalester Journal of Physics and Astronomy

We calculate oscillation probabilities in the presence of an external magnetic field in a one-generation neutrino framework that includes both Majorana and Dirac mass terms. First, we write down the Euler-Lagrange equations and obtain a system of eight differential equations coupling together eight different neutrino states that can be distinguished by helicity, chirality, and particle/antiparticle-ness. We then solve this system of differential equations in various special cases, exhibiting different types of oscillations. When the magnetic field is in the direction of momentum, there are only four oscillation channels as helicity flip is forbidden. We observe that chirality flips are ...


The Impact Of Initial Abundances On Modeling The Weak S-Process, Lev S. Serxner 2022 Macalester College

The Impact Of Initial Abundances On Modeling The Weak S-Process, Lev S. Serxner

Macalester Journal of Physics and Astronomy

No abstract provided.


The Survey Of Hi In Extremely Low-Mass Dwarfs: New Results From Vla Imaging, Francesco Pecere, John M. Cannon, Damen Beverlin, Jackson Codd 2022 Macalester College

The Survey Of Hi In Extremely Low-Mass Dwarfs: New Results From Vla Imaging, Francesco Pecere, John M. Cannon, Damen Beverlin, Jackson Codd

Macalester Journal of Physics and Astronomy

We present new HI spectral line imaging of 19 galaxies in the “Survey of HI in Extremely Low-mass Dwarfs” (SHIELD) acquired for Large Program VLA/ 20A-330. Using the National Radio Astronomy Observatory’s Karl G. Jansky Very Large Array (VLA) in the C configuration, we produce images of the neutral interstellar medium (HI) on angular scales of 15 to 20 arcseconds (corresponding to physical resolutions of 200 to 1100 parsecs). The three-dimensional cubes probe the morphology and kinematics of the gas at a range of spatial and spectral resolutions. The cubes were collapsed to produce two-dimensional moment maps (representing HI ...


Hunting For Fast Radio Bursts From Messier 82: Exploring The Frb--Magnetar Connection, Susie Paine 2022 Macalester College

Hunting For Fast Radio Bursts From Messier 82: Exploring The Frb--Magnetar Connection, Susie Paine

Macalester Journal of Physics and Astronomy

Fast radio bursts (FRBs) are short-duration radio pulses of cosmological origin. Among the most common sources predicted to explain this phenomenon are bright pulses from a class of extremely highly magnetized neutron stars known as magnetars. In 2020, a Galactic magnetar produced an FRB-like burst, allowing researchers to constrain the Galactic magnetar burst rate. We assume that the magnetar burst rate scales with star formation rate and test an important prediction for similar bursts in nearby galaxies. Messier 82 (M82) has a star formation rate 40 times that of the Milky Way, implying that the magnetar burst rate would be ...


Molecular Line Search In Archival Alma Imaging Of M87, Xueyi Li 2022 Macalester College

Molecular Line Search In Archival Alma Imaging Of M87, Xueyi Li

Macalester Journal of Physics and Astronomy

We present a molecular line search in spectral imaging of the elliptical galaxy M87 using archival data from the Atacama Large Millimeter/sub-millimeter Array (ALMA). The primary goal of this project is to verify and characterize possible CO transition lines, which can be used for future studies to determine the dynamics of the system, or the mass of the supermassive black hole (BH) in the center of the galaxy. After performing extensive atmospheric modeling, we found that most of the absorption features have a corresponding atmospheric ozone transition, so it is unlikely that these features are either Galactic or extragalactic ...


Lie Algebras And The Poincare Group, Jack Hempel Costello 2022 Macalester College

Lie Algebras And The Poincare Group, Jack Hempel Costello

Macalester Journal of Physics and Astronomy

This paper will discuss my research with
Professor Tonnis ter Veldhuis on the Poincare Group
and other similar algebraic approaches based on the
Minkowski Metric. This paper will begin with an
introduction discussing group theory and expand on its
specific applications in theoretical physics.


Simulating Interactions Between Coronal Mass Ejections, Damen S. Beverlin, Tatiana Niembro 2022 Macalester College

Simulating Interactions Between Coronal Mass Ejections, Damen S. Beverlin, Tatiana Niembro

Macalester Journal of Physics and Astronomy

Coronal mass ejections (CMEs) launch large amounts of plasma and magnetic fields into the interplanetary medium. Under the right initial conditions, this ejecta can reach Earth and cause issues with electronic devices. As such, we would like to have an accurate model that depicts how these CMEs propagate as they leave the sun. By using fluid dynamics and one-minute resolution in-situ solar wind data, we sought to simulate CME plasma propagation with analytical and numerical models. Because the interstellar medium contains other material and other events happen on the sun simultaneously, CMEs can interact with each other and other ejecta ...


Custom Calibration And Correction Of Photoemission Electron Microscope Images Using Graphene, Henry Bell 2022 Macalester College

Custom Calibration And Correction Of Photoemission Electron Microscope Images Using Graphene, Henry Bell

Macalester Journal of Physics and Astronomy

The Photoemission Electron Microscope (PEEM) is a full-field electron microscope that utilizes the photoelectric effect to image a surface. Due to a spatial resolution on the order of 10 nanometers and its ability to image both the morphology of a surface and its band structure, it is a useful tool for understanding the properties of materials for use in electronic devices. To correct for random sample misalignment and the experimental frame of reference in the spectroscopy mode of the PEEM, the 3D dataset must be rotated in both the momentum and energy coordinates which requires pixel calibration and energy alignment ...


Mastcam Multispectral Database From The Curiosity Rover’S Traverse In Gale Crater, Mars (Sols 0-2302), Melissa S. Rice 2022 Western Washington University

Mastcam Multispectral Database From The Curiosity Rover’S Traverse In Gale Crater, Mars (Sols 0-2302), Melissa S. Rice

Geology Faculty Publications

The Mars Science Laboratory (MSL) Curiosity rover has explored fluvio-deltaic, lacustrine, and aeolian strata as it climbed over 400 m in elevation over the first 2302 sols of its traverse. Curiosity’s Mast Camera (Mastcam) instrument is a pair of multispectral imagers covering visible to near-infrared (VNIR) wavelengths (445 nm - 1013 nm). Mastcam spectra can broadly distinguish between iron phases and oxidation states, and in combination with chemical data from other instruments, Mastcam spectra can help constrain mineralogy, depositional origin, and diagenesis. This dataset includes representative Mastcam spectra from >600 multispectral observations acquired across Curiosity’s traverse through Vera Rubin ...


“Lasso The Moon? Is It Possible? What About Hack The Moon? Today’S International Framework For Activities On The Moon”, Diane M. Janosek, Armando Seay, Josa P. Natera 2022 Military Cyber Professional Association

“Lasso The Moon? Is It Possible? What About Hack The Moon? Today’S International Framework For Activities On The Moon”, Diane M. Janosek, Armando Seay, Josa P. Natera

Military Cyber Affairs

The global interest in the moon and outer space continues to skyrocket. The current U.S. commercial investment in space is $350 billion annually, and it is expected to grow to $1 Trillion or more by 2040. The U.S. military investment in space defense and research likewise continues to grow, with the total investment amount remaining classified. With the frequent activity in space, as well as concerns about attacks to US space assets to and from space, the U.S, created the United States Space Command and its Space Force. With private space travel, nanosatellites, lunar exploration, and the ...


Chandra Spectral Constraints Of The Low-Metallicity Collision Ring Cartwheel Galaxy, Chloë Benton 2022 University of Arkansas, Fayetteville

Chandra Spectral Constraints Of The Low-Metallicity Collision Ring Cartwheel Galaxy, Chloë Benton

Physics Undergraduate Honors Theses

With the sophistication of the Chandra X-Ray Observatory, many observations of the behaviors of binary systems have been researched and studied. As an excellent example, for the low metallicity Cartwheel Galaxy, some fraction of the X-ray photons emitted from X-ray binaries have been intercepted by the detectors on the telescope and have been compiled into “events file.” When modeled properly, this data can produce insight into the behavior of the stellar populations in this object. The primary goal of this project is to use these events files to measure the X-ray properties of the X-ray binaries in the Cartwheel Galaxy ...


Monitoring The M-Dwarf Host Stars Of Tess Exoplanet Candidates: Stellar Flares And Habitability, Ashley Lieber 2022 University of Arkansas

Monitoring The M-Dwarf Host Stars Of Tess Exoplanet Candidates: Stellar Flares And Habitability, Ashley Lieber

Physics Undergraduate Honors Theses

In the search for life beyond our solar system, the study of M-dwarfs has become increasingly important due to their unique characteristics including their small size, flaring capabilities, and long lifespans. Their small size allows for exoplanet detection due to observable gravitational interactions, and the stellar flares could potentially trigger prebiotic life on exoplanets in the system. Lastly, their long lifespans may provide the conditions necessary to foster prebiotic life and the development of more complex organisms over time. Flare rate is a critical factor in determining the habitability of the exoplanet due to its potential to damage or incubate ...


A Monte Carlo Method For Evaluating Empirical Gyrochronology Models And Its Application To Wide Binary Benchmarks, Tomomi Otani, Ted von Hippel, Derek Buzasi, Terry Oswalt, Alexander Stone-Martinez, Patrice Majewski 2022 Embry-Riddle Aeronautical University

A Monte Carlo Method For Evaluating Empirical Gyrochronology Models And Its Application To Wide Binary Benchmarks, Tomomi Otani, Ted Von Hippel, Derek Buzasi, Terry Oswalt, Alexander Stone-Martinez, Patrice Majewski

Publications

No abstract provided.


Emergent Spectra Of Young X-Ray Emitting Populations Across Environments, Alex Siebenmorgen 2022 University of Arkansas, Fayetteville

Emergent Spectra Of Young X-Ray Emitting Populations Across Environments, Alex Siebenmorgen

Physics Undergraduate Honors Theses

We construct reasonably accurate models of the X-Ray spectra of a multitude of sources in M51. We construct both average and individual models for the sources, which are split into 16 groups as the counts per source increases. Then, we create a plot to show how the model-predicted values of column density (nH) and photon index (gamma) change with luminosity. These models will be used to create an accurate X-Ray stellar energy distribution (SED) for M51, and to better understand how the SED changes with environmental factors like metallicity and star formation rate (SFR).


Using Supervised Learning Algorithms As A Follow-Up Method In The Search Of Gravitational Waves From Core-Collapse Supernovae, Javier M. Antelis, Marco Cavaglia, Travis Hansen, Mannuel D. Morales, Claudia Moreno, Soma Mukherjee, Marek J. Szczepańczyk, Michele Zanolin 2022 The University of Texas Rio Grande Valley

Using Supervised Learning Algorithms As A Follow-Up Method In The Search Of Gravitational Waves From Core-Collapse Supernovae, Javier M. Antelis, Marco Cavaglia, Travis Hansen, Mannuel D. Morales, Claudia Moreno, Soma Mukherjee, Marek J. Szczepańczyk, Michele Zanolin

Physics and Astronomy Faculty Publications and Presentations

We present a follow-up method based on supervised machine learning (ML) to improve the performance in the search of gravitational wave (GW) bursts from core-collapse supernovae (CCSNe) using the coherent WaveBurst (cWB) pipeline. The ML model discriminates noise from signal events by using a set of reconstruction parameters provided by cWB as features. Detected noise events are discarded yielding a reduction in the false alarm rate (FAR) and the false alarm probability thus enhancing the statistical significance. We tested the proposed method using strain data from the first half of the third observing run of advanced LIGO, and CCSNe GW ...


Determining The Sources Of The Zodiacal Cloud Using Relative Velocities Of Dust Particles From High-Resolution Spectroscopy, Philip B. Mann III 2022 Embry-Riddle Aeronautical University

Determining The Sources Of The Zodiacal Cloud Using Relative Velocities Of Dust Particles From High-Resolution Spectroscopy, Philip B. Mann Iii

Beyond: Undergraduate Research Journal

The zodiacal cloud is the Solar System debris disk in which the Earth’s orbit is located. The dust that comprises the cloud comes from cometary, asteroidal, interstellar, and other source populations, but the relative ratios have proven hard to determine. However, asteroidal and cometary particles typically have different types of orbits, with asteroidal particles having more circular and lower inclination orbits than cometary particles. Accordingly, the relative velocities of these groups of particles with respect to Earth are also different, and measurements of these relative velocities can help distinguish between the sources. The spectrum of the zodiacal light contains ...


The Solar-Electric Sail: Application To Interstellar Migration And Consequences For Seti, Gregory Matloff 2022 CUNY New York City College of Technology

The Solar-Electric Sail: Application To Interstellar Migration And Consequences For Seti, Gregory Matloff

Publications and Research

The Solar-Electric Sail accelerates by reflecting positively charged solar wind ions. If it is used to propel an interstellar migration mission, its interstellar cruise velocity relative to the home star cannot exceed the solar wind velocity. In an effort to analytically determine interstellar cruise velocity for a 107 kg generation ship, a constant solar wind velocity within the heliosphere of a Sun-like star of 600 km/s is assumed. The solar wind proton density at 1 AU is also considered constant at 10 protons per cubic centimeter. Solar wind density is assumed to decrease with the inverse square of solar ...


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