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Effect Of Magnetic Draping On Satellite Galaxies In Clusters, Vanessa Brown 2024 The Graduate Center, City University of New York

Effect Of Magnetic Draping On Satellite Galaxies In Clusters, Vanessa Brown

Dissertations, Theses, and Capstone Projects

Galaxy evolution has been observed to be influenced by environment. Satellite galaxies orbiting within clusters can experience changes in morphology and composition through various mechanisms such as ram-pressure stripping (RPS), which removes a galaxy’s interstellar medium as it passes through the cluster via direct interaction with the hot intracluster medium gas. An open question is whether intracluster magnetic fields affect galaxy evolution, for example by forming a magnetic layer around infalling galaxies (called magnetic draping) and mitigating gas removal by RPS. Using the code GADGET-3, we compare global properties and mass distributions within identical cluster simulations run with and without …


Examining Galaxy Bulge Regions With The Sloan Digital Sky Survey, Sarah E. Draves, Ariyeh Maller 2024 CUNY New York City College of Technology

Examining Galaxy Bulge Regions With The Sloan Digital Sky Survey, Sarah E. Draves, Ariyeh Maller

Publications and Research

Nearly all of the ordinary matter in the universe is located in galaxies, which are made up stars, gas, dust, and black holes, and range in size from a few thousand to a few hundred thousand light years across. Galaxies come in different shapes, but many of them are spiral shaped, and some of those have a central bulge region that is distinct from the rest of the galactic disk. This project used a large data set of galaxies that had their bulge and disk components separated to see what correlations those fractions of each galaxy have with other galaxy …


Table Of Contents, 2024 University of South Carolina

Table Of Contents

Journal of the South Carolina Academy of Science

No abstract provided.


Unraveling The Physics Of Quasar Jets Using Hst Polarimetry, Devon Clautice 2024 Florida Institute of Technology

Unraveling The Physics Of Quasar Jets Using Hst Polarimetry, Devon Clautice

Theses and Dissertations

We present a multiwavelength study of three high-power FR II (quasar) jets -- 3C 273, PKS 0637-752, and 1150+497 -- with an emphasis on new high-quality Hubble Space Telescope (HST) optical polarimetry and Chandra X-ray Observatory imaging. Relativistic jets from active galactic nuclei transport energy and mass from the supermassive black hole’s accretion region out to Megaparsec-scale lobes, with effects that feedback into galaxy formation and cluster energetics. We build on recent work which has called into question our fundamental understanding of FR II jet physics, and suggest that highly-efficient particle acceleration must be taking place in situ …


Survival Of Methanogens Desiccated On Mars Soil Simulants: Implications For Life On Mars, Lanee Knight 2024 University of Arkansas, Fayetteville

Survival Of Methanogens Desiccated On Mars Soil Simulants: Implications For Life On Mars, Lanee Knight

Biological Sciences Undergraduate Honors Theses

Because of Mars’s chemical features, it can be studied in the search for life and is a significant figure in the study of astrobiology (McKay, 2010). Dr. Kral’s laboratory studies methanogens, microorganisms in the domain Archaea, as possible life forms on Mars. Since some methanogens can withstand harsh environmental conditions and emit methane as a waste product, the growth of these microorganisms can be used as an indicator of potential life in the Mars subsurface (Kral et al., 1998). In this research, four methanogens, Methanothermobacter wolfeii, Methanobacterium formicicum, Methanosarcina barkeri, and Methanococcus maripaludi were desiccated in the …


Modeling An Extra Planet's Effects On Earth, Emily Simpson 2024 Florida Institute of Technology

Modeling An Extra Planet's Effects On Earth, Emily Simpson

Aerospace, Physics, and Space Science Student Publications

Orbital dynamics play a crucial role in determining the habitability of exoplanets, and many models have been developed to study the dynamical evolution of broader planetary system structure. To further investigate the implications this has regarding planetary habitability, this project simulated the evolution of the Solar System with an additional planet orbiting in place of the Asteroid Belt using the Gravitational Rigid-body InTegrator (GRIT) package. 21 total simulations were run for 100,000 years with varying values for the extra planet’s mass (from 0.01 to 10 Earth masses) and orbital parameters (based on the 4 most massive asteroids in the Asteroid …


The Black-To-White Hole Transition, Farshid Soltani 2024 Western University

The Black-To-White Hole Transition, Farshid Soltani

Electronic Thesis and Dissertation Repository

Classically, an isolated black hole is a stable gravitational object. If however semiclassical effects are taken into account, an isolated black hole can be shown to slowly radiate its mass away in a process called evaporation. At the end of the evaporation process, when the size of the horizon becomes Planckian, the quantum nature of the gravitational field can no longer be neglected and the dynamics of the horizon is governed by quantum gravity. The main objective of this thesis is the systematic investigation of a tentative scenario for the “end of the life” of a black hole: the black-to-white …


Simulating Continuous Gravitational Waves, Ivan Mihael Villalba Moran 2024 Fort Hays State University

Simulating Continuous Gravitational Waves, Ivan Mihael Villalba Moran

SACAD: John Heinrichs Scholarly and Creative Activity Days

Using a table-top Michelson Interferometer to replicate Laser Interferometer Gravitational-Wave Observatory (LIGO) arrangement, we use sound waves to simulate Continuous Gravitational Waves (CWs). Using the NumPy package in Python programming, we recover the frequency of the injected sinusoidal signal using the mathematics of the Fourier Transform. Currently, we are trying to implement the Hidden Markov Model along with the Viterbi Algorithm as a method to detect Wandering Continuous Gravitational Waves.


The Jesuit Tradition Of Astronomy At Holy Cross, Sarah Campbell M.A., M.S.I.S. 2024 College of the Holy Cross

The Jesuit Tradition Of Astronomy At Holy Cross, Sarah Campbell M.A., M.S.I.S.

Staff publications

This paper summarizes the study of astronomy and related fields as part of the curriculum at the College of the Holy Cross. It briefly profiles four Jesuit priests who were associated with Holy Cross and made significant contributions to the study of astronomy, solar physics and other scientific disciplines. The history of a campus observatory is briefly described as well.

This paper was presented an event sponsored by the Holy Cross Libraries to commemmorate the solar exclipse which occurred April 8. 2024.


Factors Predicting Public’S Willingness To Support National Aeronautics And Space Administration’S Artemis Mission, Sean Crouse 2024 Embry-Riddle Aeronautical University

Factors Predicting Public’S Willingness To Support National Aeronautics And Space Administration’S Artemis Mission, Sean Crouse

Doctoral Dissertations and Master's Theses

NASA's Artemis program aspires to return astronauts to the moon and aims to land the first woman and person of color on the lunar surface. The endeavor symbolizes the next evolution in space exploration and serves as a testament to the human spirit of discovery. In the face of this significant undertaking, gauging public sentiment and understanding the factors driving public support becomes necessary. The current study aimed to address a critical gap in the literature by examining public support for NASA’s Artemis mission, which is essential for sustaining the program’s momentum and cultivating a culture of innovation and exploration. …


Moid Using New Sets Of Universal Functions, AYMAN HOMDA, Hany R. Dwidar, Abdelaziz A. Bakry, M.N. Mohamad Ismail, AHMED El-RAFFIE 2024 Egyptian Space Agency, Cairo, Egypt, 130

Moid Using New Sets Of Universal Functions, Ayman Homda, Hany R. Dwidar, Abdelaziz A. Bakry, M.N. Mohamad Ismail, Ahmed El-Raffie

Al-Azhar Bulletin of Science

In this paper, based on Goodyear's time transformation formula, we used a set of modified universal functions to construct the minimum distance function between any two celestial objects. We determined the distance between objects in space under a specific time constraint. We used the continued fractions method for quick convergence of the distance function. We used the inverse series to obtain a first initial guess to solve the convergence equation. Furthermore, the Lagrange multiplier method was used to determine the minimum distance between the two objects under the specified time constraint. We constructed an algorithm and applied it with the …


Reflectance Spectroscopy Datasets For The Validation Of Tanager, Kristiana Lapo, Kathleen Hoza, Sammy Theuer, Melissa S. Rice 2024 Western Washington University

Reflectance Spectroscopy Datasets For The Validation Of Tanager, Kristiana Lapo, Kathleen Hoza, Sammy Theuer, Melissa S. Rice

Geology Faculty Publications

The Three-Axis N-sample Automated Goniometer for Evaluating Reflectance (TANAGER) is a custom goniometer designed to rapidly acquire spectra of natural rock surfaces across the full scattering hemisphere. TANAGER interfaces with a Malvern Panalytical ASD Fieldspec 4 Hi-Res reflectance spectrometer to collect data from 350-2500 nm at a range of incidence, emission and azimuth angles. To validate the accuracy and repeatability of data collected with TANAGER - and to characterize any instrument noise, artifacts or sample heating effects - we collected spectra from three categories of targets: (1) powdered calcium sulfate (anhydrite), (2) naturally weathered basalt surfaces, and (3) color calibration …


Characterizing And Mitigating Transient Noise In Ligo Observatories For Gravitational Wave Detection, Jane Glanzer 2024 Louisiana State University at Baton Rouge

Characterizing And Mitigating Transient Noise In Ligo Observatories For Gravitational Wave Detection, Jane Glanzer

LSU Doctoral Dissertations

The existence of gravitational waves is predicted by Albert Einstein's Theory of General Relativity. Commonly referred to as "ripples in spacetime", these waves are generated by some of the most violent and energetic processes in the universe. Despite their theoretical prediction over a century ago, it wasn't until 2015 that the Advanced LIGO (aLIGO) interferometers in Hanford, WA and Livingston, LA directly detected gravitational waves for the first time, confirming Einstein's theory and ushering in a new era of astrophysics.

Detecting gravitational waves requires incredible precision. Because of the extreme sensitivity required, it is possible for the gravitational wave data …


Automated Identification And Mapping Of Interesting Mineral Spectra In Crism Images, Arun M. Saranathan 2024 University of Massachusetts Amherst

Automated Identification And Mapping Of Interesting Mineral Spectra In Crism Images, Arun M. Saranathan

Doctoral Dissertations

The Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) has proven to be an invaluable tool for the mineralogical analysis of the Martian surface. It has been crucial in identifying and mapping the spatial extents of various minerals. Primarily, the identification and mapping of these mineral spectral-shapes have been performed manually. Given the size of the CRISM image dataset, manual analysis of the full dataset would be arduous/infeasible. This dissertation attempts to address this issue by describing an (machine learning based) automated processing pipeline for CRISM data that can be used to identify and map the unique mineral signatures present in …


Toltec: A New Multichroic Imaging Polarimeter For The Large Millimeter Telescope, Nat S. DeNigris 2024 University of Massachusetts Amherst

Toltec: A New Multichroic Imaging Polarimeter For The Large Millimeter Telescope, Nat S. Denigris

Doctoral Dissertations

The TolTEC camera is a new millimeter-wave imaging polarimeter designed to fill the focal plane of the 50-m diameter Large Millimeter Telescope (LMT). Combined with the LMT, TolTEC offers high angular resolution (5", 6.3", 9.5") for simultaneous, polarization-sensitive observations in its three wavelength bands: 1.1, 1.4, and 2.0 mm. Additionally, TolTEC is designed to reach groundbreaking mapping speeds in excess of 1 deg2/mJy2/hr, which will enable the completion of deep surveys of large-scale structure, galaxy evolution, and star formation that are currently limited when considering practical observation times for other ground-based observatories. This thesis covers the …


Poleward Moving Auroral Forms And Magnetic Reconnection, Gasia Excel, Gerard Fasel, Julia Johnson, Jordana Xu, Parker Para, Amiel Silbol, Rachel Rodriguez, John Mann 2024 Pepperdine University

Poleward Moving Auroral Forms And Magnetic Reconnection, Gasia Excel, Gerard Fasel, Julia Johnson, Jordana Xu, Parker Para, Amiel Silbol, Rachel Rodriguez, John Mann

Seaver College Research And Scholarly Achievement Symposium

Magnetic reconnection on the dayside magnetosphere is one of the main mechanisms for the solar wind to transfer energy and momentum to the terrestrial environment. This process is assumed to be most effective when the interplanetary magnetic field (IMF) is southward. Poleward moving auroral forms (PMAFs) have been identified in past studies as ionospheric signatures of magnetic reconnection on the dayside. The PMAFs occurring for the positive/(negative) IMF y-component first expanded westward(dawn)/eastward(dusk) before propagating poleward. This PMAF study presents a comprehensive set of events where the initial brightening moves through a pre-existing dayside auroral arc westward(dawn)/eastward(dusk) when the IMF y-component …


Dayside Pulsating Diffuse Aurora And The Interplanetary Magnetic Field, Thomas Lewer, Gerard J. Fasel, Maxwell Fargo, Ethan Swonger, S. Lee, Aidan Hulbert, Owen Bradley, Arman Manookian, Tommy Cleaveland, B. Yonano, John Mann, F. Sigernes, D. Lorentzen 2024 Pepperdine University

Dayside Pulsating Diffuse Aurora And The Interplanetary Magnetic Field, Thomas Lewer, Gerard J. Fasel, Maxwell Fargo, Ethan Swonger, S. Lee, Aidan Hulbert, Owen Bradley, Arman Manookian, Tommy Cleaveland, B. Yonano, John Mann, F. Sigernes, D. Lorentzen

Seaver College Research And Scholarly Achievement Symposium

Changes in the interplanetary magnetic field (IMF) orientation can affect pulsations in the dayside aurora. It has been reported that multiple dayside arcs(Pc 5 band) were replaced by diffuse pulsating aurora (Pc 3-4 band) when the IMF turned northward. Dayside green (557.7 nm emission) pulsating aurora had been reported to occur between 0800 and 1100 MLT (0500-0800 UT) in patches. The pulsations are normally associated with Pc 3-5 range. This statistical study examines pulsating green aurora using ground-based optical data are obtained from the Kjell Henriksen Observatory (KHO) in Longyearbyen, Svalbard (GEO: N, E; AACGM: N, E). All-Sky Camera images …


Neutrino’S Non-Zero Electric Potential As An Origin Of Gravitation, Domain Structure And Expansion Of The Universe., Polievkt Perov 2024 Suffolk University

Neutrino’S Non-Zero Electric Potential As An Origin Of Gravitation, Domain Structure And Expansion Of The Universe., Polievkt Perov

College of Arts & Sciences Faculty Works

The axial electric potentials of neutrinos as neutral composite structures, while being very small at large distances, do not vanish, and the same can be said about the neutrino “asymmetric dipoles” (paired neutrinos of not the same kind). Depending on the orientation of the “asymmetric dipole”, its far-field electric potential in some direction can be positive or negative, interacting with other “dipoles” at that large distance attractively or repulsively depending on their mutual orientation. The mutual orientation of the dipoles locally (inside a galaxy) might be such that they are aligned and experience the attractive force toward the local center …


Density And Magnetic Field Asymmetric Kelvin‐Helmholtz Instability, Xuanye Ma, Peter Delamere, Katariina Nykyri, Antonius Otto, Stefan Eriksson, Lihui Chai, Brandon Burkholder, Andrew Dimmock, Yu-Lun Liou, Shiva Kavosi 2024 Embry-Riddle Aeronautical University

Density And Magnetic Field Asymmetric Kelvin‐Helmholtz Instability, Xuanye Ma, Peter Delamere, Katariina Nykyri, Antonius Otto, Stefan Eriksson, Lihui Chai, Brandon Burkholder, Andrew Dimmock, Yu-Lun Liou, Shiva Kavosi

Publications

The Kelvin‐Helmholtz (KH) instability can transport mass, momentum, magnetic flux, and energy between the magnetosheath and magnetosphere, which plays an important role in the solar‐wind‐ magnetosphere coupling process for different planets. Meanwhile, strong density and magnetic field asymmetry are often present between the magnetosheath (MSH) and magnetosphere (MSP), which could affect the transport processes driven by the KH instability. Our magnetohydrodynamics simulation shows that the KH growth rate is insensitive to the density ratio between the MSP and the MSH in the compressible regime, which is different than the prediction from linear incompressible theory. When the interplanetary magnetic field (IMF) …


Adsorption Of Crystal Violet Dye From Synthetic Wastewater By Ball-Milled Royal Palm Leaf Sheath, Neloy Sen, Nawrin Rahman Shefa, Kismot Reza, Sk Md Ali Zaker Shawon, Md. Wasikur Rahman 2024 The University of Texas Rio Grande Valley

Adsorption Of Crystal Violet Dye From Synthetic Wastewater By Ball-Milled Royal Palm Leaf Sheath, Neloy Sen, Nawrin Rahman Shefa, Kismot Reza, Sk Md Ali Zaker Shawon, Md. Wasikur Rahman

Physics and Astronomy Faculty Publications and Presentations

The current study shows that using a batch approach to remove crystal violet dye from synthetic wastewater is feasible when using royal palm leaf sheath powder as an adsorbent. In order to investigate the effects of many parameters, including starting concentration, pH effect, dye concentration, adsorbent dose, contact time, and temperature, experiments were carried out under various operating conditions. Maximum removal was obtained at pH 6 and at a concentration of 100 ppm, which are considered as ideal values. The influence of pH and dye concentration was shown to be substantial. Langmuir, Freundlich, and Temkin isotherm models were fitted to …


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