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Full-Text Articles in Physics

Table Of Contents May 2024

Table Of Contents

Journal of the South Carolina Academy of Science

No abstract provided.


Synchronicity: An Analysis Of Einstein's Halfway Rule, Preslava Nikolova Jan 2024

Synchronicity: An Analysis Of Einstein's Halfway Rule, Preslava Nikolova

Rushton Journal of Undergraduate Humanities Research

For the modern world to function, Global Positioning System satellites must synchronize to clocks on Earth. This paper examines a concept that underlies GPS systems, namely Albert Einstein’s halfway rule—the idea that a line of simultaneity exists between two events in different systems. This essay discusses how Einstein used conventionalist methods to establish ½ as a constant value for σ to take advantage of the property of symmetry.


Genealogical Vs Phylogenetic Mutation Rates: Answering A Challenge, Robert Carter Dec 2023

Genealogical Vs Phylogenetic Mutation Rates: Answering A Challenge, Robert Carter

Proceedings of the International Conference on Creationism

There is a discrepancy between the mutation rate we can measure today and the rate at which evolution is supposed to have proceeded. The former is sometimes called the genealogical mutation rate, for it is obtained by comparing individuals whom we know to be related. The latter is sometimes called the phylogenetic mutation rate. It is calculated by counting the fixed differences between two species and dividing by the estimated time since their common ancestor. Genealogical mutation rates are generally several orders of magnitude faster than phylogenetic estimates. This causes problems for the evolutionary model. For example, using the genealogical …


Development Of A Particle-In-Cell/Monte Carlo Simulation For Weakly Ionized Plasmas, Xiaochuan (Chloe) Zheng, James Doyle Jun 2023

Development Of A Particle-In-Cell/Monte Carlo Simulation For Weakly Ionized Plasmas, Xiaochuan (Chloe) Zheng, James Doyle

Macalester Journal of Physics and Astronomy

A plasma is a gaseous system that contains large numbers of electrons and ions that are subject to forces produced by electric and magnetic fields. Weakly ionized plasmas, where the plasma density is much lower than the background gas density, are common in laboratory, atmospheric, and astrophysical situations. Theoretical calculations of plasma properties are challenging due to the complexity of the differential equations used to characterize fundamental physics. Particle-in-cell (PIC) simulations bypass the mathematical difficulties associated with analytic models, at the expense of more complex and time-consuming computer calculations. In this work we developed a one dimensional PIC simulation of …


Tools For Refining The Baryonic Tully-Fisher Relation, Ezra D. Wolf Jun 2023

Tools For Refining The Baryonic Tully-Fisher Relation, Ezra D. Wolf

Macalester Journal of Physics and Astronomy

This paper discusses the development of tools for galactic photometry using wise, and for reduction and analysis of 21cm galaxy spectra. These Python-based tools can then be applied to selected data in order to refine the Baryonic Tully-Fisher Relation. This relation, between baryonic mass and rotational velocity of a galaxy, proves useful for extragalactic research, particularly in calculating redshift-independent distances. While these tools could be further improved, they provide a robust process for calculation of particular galaxy characteristics.


Hydrosphere: Modeling The Planetary Structure Of Ocean Planets And Icy Moons, Karlee R. Taylor Jun 2023

Hydrosphere: Modeling The Planetary Structure Of Ocean Planets And Icy Moons, Karlee R. Taylor

Macalester Journal of Physics and Astronomy

In recent years, “water worlds” have become increasingly of interest to astrobiologists due to their high potential for habitability, as the large amount water on their surfaces is not only necessary for life, but also promises long-term climatic stability. However, also necessary for life is the exchange of chemical compounds between the geosphere and the hydrosphere - something which may be ob- structed by the presence of high pressure ices on these ocean planets and icy moons. In order to explore the habitability of bodies with various surface temperatures, water masses, and core radii, this project develops a model of …


From Experiment To Theory: Investigate The Effect Of Pump Beam Size On Photovoltaic Material Behavior, Dengyu Tu Jun 2023

From Experiment To Theory: Investigate The Effect Of Pump Beam Size On Photovoltaic Material Behavior, Dengyu Tu

Macalester Journal of Physics and Astronomy

In orde to investigate the effect of the pump beam size on an ultrafast conductivity measurement experiment, an experiment using Femto XL-500 laser and a simulation using Mathematica were performed. From the experiment data, we found that as the size of the pump beam decreases beyond certain limit, the Drude model can not accurately predict the relationship between conductivity and frequency. In addition, the simulation results corroborate with the experiment result that there is a limit for the size of the pump beam.


Machine Learning Refinements To Metallicity-Dependent Isotopic Abundances, Haoxuan Sun Jun 2023

Machine Learning Refinements To Metallicity-Dependent Isotopic Abundances, Haoxuan Sun

Macalester Journal of Physics and Astronomy

The project aims to use machine learning algorithms to fit the free parameters of an isotopic scaling model to elemental observations. The processes considered are massive star nucleosynthesis, Type Ia SNe, the s-process, the r-process, and p-isotope production. The analysis on the successful fits seeks to minimize the reduced chi squared between the model and the data. Based upon the successful refinement of the isotopic parameterized scaling model, a table providing the 287 stable isotopic abundances as a function of metallicity, separated into astrophysical processes, is useful for identifying the chemical history of them. The table provides a complete averaged …


Machine Learning Applications For Materials Science: Predicting Properties Of Two-Dimensional Magnetic Materials, Paige Stevenson Jun 2023

Machine Learning Applications For Materials Science: Predicting Properties Of Two-Dimensional Magnetic Materials, Paige Stevenson

Macalester Journal of Physics and Astronomy

We trained successful neural networks to predict the formation energy and magnetic moment of 2-dimensional ferromagnetic materials of similar structure to Cr2Ge2Te6. We collect elemental data on materials with known and unknown properties from easily accessible sources to screen for viable materials for use in future research. Random forest regressors were used to identify the most important predictors of our target qualities, which perform better on predictions of formation energy than magnetic moment. We predict the properties of 1225 materials that are candidates for further research in two-dimensional magnetism and identify several potential sources of error in our models that …


Fabricating Perovskite Solar Cells: Fabrication Guide For Limited Lab Capabilities, Erin F. S. Leary Jun 2023

Fabricating Perovskite Solar Cells: Fabrication Guide For Limited Lab Capabilities, Erin F. S. Leary

Macalester Journal of Physics and Astronomy

Within the realm of emerging photovoltaics, Perovskite cells are one of the most intriguing technologies. Within a little over a decade, Perovskite solar cells have rivaled the efficiencies of traditional silicon solar cells and strongly outpaced other emerging photovoltaic technologies. This paper aims to show a fabrication guide for creating Perovskite solar cells in a limited lab setting. The fabrication guide created structures with strong physical reliability, but limited electrical reliability. More research is needed to ensure greater reliability and proper electrical function.


Solar Radio Bursts —Deployable Low-Band Ionosphere And Transients Experiment (Dlite) Arrays, Jonathan M. Kazor, Jason Kooi Jun 2023

Solar Radio Bursts —Deployable Low-Band Ionosphere And Transients Experiment (Dlite) Arrays, Jonathan M. Kazor, Jason Kooi

Macalester Journal of Physics and Astronomy

Solar radio bursts, phenomenon that often accompany CME, solar flares and other solar events, can be detected on earth and used in the prediction of solar weather that affects earth systems in several ways. As part of the NREIP Program supporting the Naval Research Laboratory, Remote Sensing Division, approximately ten interns participated in the analysis of data collected by DLITE and WAVES radio data. Data from DLITE is often used as a complement to data from WAVES due to differences in frequency range and resolution. The analysis helps to correlate the DLITE data with the data collected from other sources. …


Mapping The Tesseral Field Of Saturn, Aurora Hiveley Jun 2023

Mapping The Tesseral Field Of Saturn, Aurora Hiveley

Macalester Journal of Physics and Astronomy

Saturn's rotation rate is still uncertain, and while it is theorized to exhibit differential rotation much like Jupiter, this claim is somewhat disputed. By analyzing the properties of waves in the ring system of Saturn as measured by the Cassini spacecraft, we aim to provide observational evidence of this phenomenon. The results of wave analysis allow us to characterize the perturbers responsible for the production of these waves, which are believed to be mass anomalies in the interior of Saturn itself. By calculating the masses of these anomalies and attempting to pinpoint their locations inside of the planet, we provide …


Trinification With A Bi-Adjoint Higgs Field, Ross Ferguson Jun 2023

Trinification With A Bi-Adjoint Higgs Field, Ross Ferguson

Macalester Journal of Physics and Astronomy

In this paper, we propose a novel extension of the Standard Model of particle physics, based on the trinification gauge group $SU(3)_C \times SU(3)_L \times SU(3)_R$. Symmetry breaking is achieved using a bi-adjoint Higgs field (transforming under the left- and right-handed subgroups) along with a more conventional bi-triplet to ensure the correct breaking and pattern of fermion masses. To preserve a discrete $Z_2$ symmetry (T-parity), we also introduce a right-handed triplet to completely break trinification symmetry to the Standard Model. The minimization conditions and conditions for the boundedness of the potential for this model are calculated. Additionally, the Standard Model …


Adding Classical Novae Contribution To The Isotopic Scaling Model, Mengxi Chen Jun 2023

Adding Classical Novae Contribution To The Isotopic Scaling Model, Mengxi Chen

Macalester Journal of Physics and Astronomy

The Isotopic Scaling model(West & Heger, 2013) provides a complete average isotopic decomposition for our Milky Way as a function of metallicity and it requires an initial Solar Abundance Decomposition as a starting point. The previous Solar Abundance decomposition work is not perfect(West & Heger, 2013), since Classical Novae abundances are ignored. My research intends to improve the current solar abundance decomposition by adding Classical Novae Abundance contribution, then to update the Isotopic Scaling model.


Table Of Contents May 2023

Table Of Contents

Journal of the South Carolina Academy of Science

No abstract provided.


Improvements To Isru For Rocket Fuel Generation, Justin Sharp May 2023

Improvements To Isru For Rocket Fuel Generation, Justin Sharp

James Madison Undergraduate Research Journal (JMURJ)

The development of efficient in-situ resource utilization (ISRU) technologies is crucial for the establishment of an extraterrestrial, self-sustaining colony. The generation of rocket fuel at potential colony locations is necessary to provide the transportation of people and cargo to and from these locations.Three processes are discussed for the improvement of ISRU methods to generate rocket fuel: electrolysis and electrochemical improvements to the process of crude fuel production, physical and chemical methods for separation of gaseous H2 and O2, and materials and cryogenics engineering for storage and transportation of liquid hydrogen (LH2) and liquid oxygen (LOX). Storage and transportation of cryogenics …


Table Of Contents Oct 2022

Table Of Contents

Journal of the South Carolina Academy of Science

No abstract provided.


2022 Scas Annual Meeting Program And Bulletin Oct 2022

2022 Scas Annual Meeting Program And Bulletin

Journal of the South Carolina Academy of Science

No abstract provided.


Continuum Damping Effects In Nuclear Collisions, Hossein Sadeghi, Mahdieh Ghafouri Aug 2022

Continuum Damping Effects In Nuclear Collisions, Hossein Sadeghi, Mahdieh Ghafouri

Karbala International Journal of Modern Science

The Time-Dependent Skyrme Hartree-Fock (TDSHF) calculations have been conducted to study 100Sn+16O, 116Sn+16O, and 122Sn+16O collisions on a 3-Dimensional (3D) mesh with SV-bas SF. For the 100Sn+16O collision, the continuum damping width of the rotational amplitudes in Ecm = 100, 150, 200, and 250 MeV has been achieved around 108, 185, 277, and 318, with the time evolution width for z2 around 15/5, 13/5, 13/9, or 14/3 fm2. The quadrupole deformation, kinetic energy, and rotational amplitude are studied. It is seen that the compound nucleus becomes uniform and spherical as time grows. The results of the time evolution show the …


Table Of Contents Jun 2022

Table Of Contents

Journal of the South Carolina Academy of Science

No abstract provided.


Twisting Lasers With The Faraday Effect, Harrison Werrell May 2022

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 May 2022

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 May 2022

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 suppressed …


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

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 May 2022

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 mass …


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

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 May 2022

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. We …


Lie Algebras And The Poincare Group, Jack Hempel Costello May 2022

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 May 2022

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 May 2022

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. …