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Radio Insights Into Gamma-Ray Mysteries, Seth M. Bruzewski 2023 University of New Mexico

Radio Insights Into Gamma-Ray Mysteries, Seth M. Bruzewski

Physics & Astronomy ETDs

In the time since its launch, the \textit{Fermi Gamma-Ray Space Telescope} has provided new and unparalleled views of the $\gamma$-ray sky, dramatically increasing our understanding of sources of high-energy radiation. During that same time, however, its ``unassociated'' sources have provided a consistent mystery: approximately one third of the modern gamma-ray sky remains completely unaccounted for in other electromagnetic regimes. While some of the fainter sources simply pose challenges in achieving the necessary signal-to-noise ratio, others are well constrained and have resisted traditional investigations for years, and in some cases, for over a decade. Radio astronomy has traditionally been the best …


Modeling Lithographic Quantum Dots And Donors For Quantum Computation And Simulation, Mitchell Ian Brickson 2023 University of New Mexico

Modeling Lithographic Quantum Dots And Donors For Quantum Computation And Simulation, Mitchell Ian Brickson

Physics & Astronomy ETDs

Our first focus is on few-hole quantum dots in germanium. We use discontinous Galerkin methods to discretize and solve the equations of a highly detailed k·p model that describes these systems, enabling a better understanding of experimental magnetospectroscopy results. We confirm the expected anisotropy of single-hole g-factors and describe mechanisms by which different orbital states have different g-factors. Building on this, we show that the g-factors in Ge holes are suciently sensitive to details of the device electrostatics that magnetospectroscopy data can be used to make a prediction of the underlying confinement potential. The second focus is on designing quantum …


Stability Of Metal Fluoride Films When Irradiated With Electron Beam, Devin M. Lewis, Waseem Ashraf 2023 Brigham Young University

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 …


Celestial Bodies, Rebecca L. Rand, Mark Popinchalk 2023 Craig Newmark Graduate School of Journalism

Celestial Bodies, Rebecca L. Rand, Mark Popinchalk

Capstones

Most of us will never come close to touching space. But space touches us every day. On Celestial Bodies, journalist Rebecca Rand and astronomer Mark Popinchalk explore the ways outer space interacts with life on earth.

In Episode 1, hosts Rebecca Rand and Mark Popinchalk explore how, for millions of years, trees have been recording celestial events in space. Within the rings of their trunks, trees store radiation from solar flares, supernovae, and changes in the earth’s magnetic field. The hosts talk to Dr. Ben Pope to learn more about what we can discover by looking at radioactive molecules …


The High Energy X-Ray Probe (Hex-P): A New Window Into Neutron Star Accretion, R.M. Ludlam, C. Malacaria, E. Sokolova-Lapa, F. Fuerst, P. Pradhan, A.W. Shaw, K. Pottschmidt, S. Pike, G. Vasilopoulos, J. Wilms, J.A. Garcia, K. Madsen, D. Stern, C. Maitra, M. Del Santo, D.J. Walton, M.C. Brumback, J. van den Eijnden 2023 Embry-Riddle Aeronautical University

The High Energy X-Ray Probe (Hex-P): A New Window Into Neutron Star Accretion, R.M. Ludlam, C. Malacaria, E. Sokolova-Lapa, F. Fuerst, P. Pradhan, A.W. Shaw, K. Pottschmidt, S. Pike, G. Vasilopoulos, J. Wilms, J.A. Garcia, K. Madsen, D. Stern, C. Maitra, M. Del Santo, D.J. Walton, M.C. Brumback, J. Van Den Eijnden

Publications

Accreting neutron stars (NSs) represent a unique laboratory for probing the physics of accretion in the presence of strong magnetic fields (B ≳ 108 G). Additionally, the matter inside the NS itself exists in an ultra-dense, cold state that cannot be reproduced in Earth-based laboratories. Hence, observational studies of these objects are a way to probe the most extreme physical regimes. Here we present an overview of the field and discuss the most important outstanding problems related to NS accretion. We show how these open questions regarding accreting NSs in both low-mass and high-mass X-ray binary systems can …


Separated Twins Or Just Siblings? A Multiplanet System Around An M Dwarf Including A Cool Sub-Neptune, M. Harris, D. Dragomir, I. Mireles, K. A. Collins, S. Ulmer-Moll, S. B. Howell, K. G. Stassun, G. Zhou, C. Ziegler, F. Bouchy, C. Briceño, D. Charbonneau, K. I. Collins, G. Fűűrész, N. M. Guerrero, J. M. Jenkins, Eric L.N. Jensen, M. H. K. Kristiansen, N. Law, M. Lendl, A. W. Mann, H. P. Osborn, S. N. Quinn, G. R. Ricker, R. P. Schwarz, S. Seager, E. B. Ting, R. Vanderspek, D. Watanabe, J. N. Winn 2023 Swarthmore College

Separated Twins Or Just Siblings? A Multiplanet System Around An M Dwarf Including A Cool Sub-Neptune, M. Harris, D. Dragomir, I. Mireles, K. A. Collins, S. Ulmer-Moll, S. B. Howell, K. G. Stassun, G. Zhou, C. Ziegler, F. Bouchy, C. Briceño, D. Charbonneau, K. I. Collins, G. Fűűrész, N. M. Guerrero, J. M. Jenkins, Eric L.N. Jensen, M. H. K. Kristiansen, N. Law, M. Lendl, A. W. Mann, H. P. Osborn, S. N. Quinn, G. R. Ricker, R. P. Schwarz, S. Seager, E. B. Ting, R. Vanderspek, D. Watanabe, J. N. Winn

Physics & Astronomy Faculty Works

We report the discovery of two TESS sub-Neptunes orbiting the early M dwarf TOI-904 (TIC 261257684). Both exoplanets, TOI-904 b and c, were initially observed in TESS Sector 12 with twin sizes of 2.426 (+0.163)/(-0.157) and 2.167 (+0.130)/(-0.118) R⊕, respectively. Through observations in five additional sectors in the TESS primary mission and the first and second extended missions, the orbital periods of the planets were measured to be 10.887 ± 0.001 and 83.999 ± 0.001 days, respectively. Reconnaissance radial velocity measurements (taken with EULER/CORALIE and SMARTS/CHIRON) and high-resolution speckle imaging with adaptive optics (obtained from SOAR/HRCAM and Gemini …


Jwst: Deuterated Pahs, Pah-Nitriles, And Pah 4 Overtone And Combination Bands I: Program Description And First Look, C. Boersma, L. J. Allamandola, Vincent J. Esposito, A. Maragkoudakis, J. D. Bregman, P. Temi, T. J. Lee, R. C. Fortenberry, E. Peeters 2023 NASA Ames Research Center

Jwst: Deuterated Pahs, Pah-Nitriles, And Pah 4 Overtone And Combination Bands I: Program Description And First Look, C. Boersma, L. J. Allamandola, Vincent J. Esposito, A. Maragkoudakis, J. D. Bregman, P. Temi, T. J. Lee, R. C. Fortenberry, E. Peeters

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

A first look is taken at the NIRSpec 1–5 μm observations from James Webb Space Telescope program 1591 that targets seven objects along the low-mass stellar life cycle with polycyclic aromatic hydrocarbon (PAH) emission. Spectra extracted from a 1'.'5 radius circular aperture are explored, showing a wealth of features, including the 3 μm PAH complex, the PAH continuum, and atomic and molecular emission lines from H i, He, H2, and other species. CO2- and H2O-ice absorption and CO emission is also seen. Focusing on the bright-PDR position in M17, the PAH CH stretch falls …


Gwtc-3: Compact Binary Coalescences Observed By Ligo And Virgo During The Second Part Of The Third Observing Run, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, Teviet Creighton, Mario C. Diaz, F. Llamas, Soma Mukherjee, Volker Quetschke, Wenhui Wang 2023 The University of Texas Rio Grande Valley

Gwtc-3: Compact Binary Coalescences Observed By Ligo And Virgo During The Second Part Of The Third Observing Run, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, Teviet Creighton, Mario C. Diaz, F. Llamas, Soma Mukherjee, Volker Quetschke, Wenhui Wang

Physics & Astronomy Faculty Publications

The third Gravitational-Wave Transient Catalog (GWTC-3) describes signals detected with Advanced LIGO and Advanced Virgo up to the end of their third observing run. Updating the previous GWTC-2.1, we present candidate gravitational waves from compact binary coalescences during the second half of the third observing run (O3b) between 1 November 2019, 15∶00 Coordinated Universal Time (UTC) and 27 March 2020, 17∶00 UTC. There are 35 compact binary coalescence candidates identified by at least one of our search algorithms with a probability of astrophysical origin ��astro>0.5. Of these, 18 were previously reported as low-latency public alerts, and 17 are reported …


Gwtc-3: Compact Binary Coalescences Observed By Ligo And Virgo During The Second Part Of The Third Observing Run, R. Abbott, T. Abbott, F. Acernese, K. Ackley, Teviet Creighton, Mario C. Diaz, Soma Mukherjee, Volker Quetschke, Wenhui Wang, Francisco Llamas 2023 The University of Texas Rio Grande Valley

Gwtc-3: Compact Binary Coalescences Observed By Ligo And Virgo During The Second Part Of The Third Observing Run, R. Abbott, T. Abbott, F. Acernese, K. Ackley, Teviet Creighton, Mario C. Diaz, Soma Mukherjee, Volker Quetschke, Wenhui Wang, Francisco Llamas

Physics & Astronomy Faculty Publications

The third Gravitational-Wave Transient Catalog (GWTC-3) describes signals detected with Advanced LIGO and Advanced Virgo up to the end of their third observing run. Updating the previous GWTC-2.1, we present candidate gravitational waves from compact binary coalescences during the second half of the third observing run (O3b) between 1 November 2019, 15 ∶ 00 Coordinated Universal Time (UTC) and 27 March 2020, 17 ∶ 00 UTC. There are 35 compact binary coalescence candidates identified by at least one of our search algorithms with a probability of astrophysical origin p astro > 0.5 . Of these, 18 were previously reported as low-latency …


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 2023 Brigham Young University - Provo

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 …


Uv-Optical Emission Of Ab Aur B Is Consistent With Scattered Stellar Light, Yifan Zhou, Brendan P. Bowler, Haifeng Yang, Aniket Sanghi, Gregory J. Herczeg, Adam L. Kraus, Jaehan Bae, Feng Long, Katherine B. Follette, Kimberly Ward-Duong, Zhaohuan Zhu, Lauren Biddle, Laird M. Close, Lillian Yushu Jiang, Ya Lin Wu 2023 The University of Texas at Austin

Uv-Optical Emission Of Ab Aur B Is Consistent With Scattered Stellar Light, Yifan Zhou, Brendan P. Bowler, Haifeng Yang, Aniket Sanghi, Gregory J. Herczeg, Adam L. Kraus, Jaehan Bae, Feng Long, Katherine B. Follette, Kimberly Ward-Duong, Zhaohuan Zhu, Lauren Biddle, Laird M. Close, Lillian Yushu Jiang, Ya Lin Wu

Astronomy: Faculty Publications

The proposed protoplanet AB Aur b is a spatially concentrated emission source imaged in the millimeter-wavelength disk gap of the Herbig Ae/Be star AB Aur. Its near-infrared spectrum and absence of strong polarized light have been interpreted as evidence supporting the protoplanet interpretation. However, the complex scattered-light structures in the AB Aur disk pose challenges in resolving the emission source and interpreting the true nature of AB Aur b. We present new images of the AB Aur system obtained using the Hubble Space Telescope Wide Field Camera 3 in the ultraviolet (UV) and optical bands. AB Aur b and the …


The Comprehensive Archive Of Substellar And Planetary Accretion Rates, S. K. Betti, K. B. Follette, K. Ward-Duong, A. E. Peck, Y. Aoyama, J. Bary, B. Dacus, S. Edwards, G. D. Marleau, K. Mohamed, J. Palmo, C. Plunkett, C. Robinson, H. Wang 2023 University of Massachusetts Amherst

The Comprehensive Archive Of Substellar And Planetary Accretion Rates, S. K. Betti, K. B. Follette, K. Ward-Duong, A. E. Peck, Y. Aoyama, J. Bary, B. Dacus, S. Edwards, G. D. Marleau, K. Mohamed, J. Palmo, C. Plunkett, C. Robinson, H. Wang

Astronomy: Faculty Publications

Accretion rates ( M ̇ ) of young stars show a strong correlation with object mass (M); however, extension of the M ̇ - M relation into the substellar regime is less certain. Here, we present the Comprehensive Archive of Substellar and Planetary Accretion Rates (CASPAR), the largest compilation to date of substellar accretion diagnostics. CASPAR includes: 658 stars, 130 brown dwarfs, and 10 bound planetary mass companions. In this work, we investigate the contribution of methodological systematics to scatter in the M ̇ - M relation and compare brown dwarfs to stars. In our analysis, we rederive all quantities …


First Vlti/Gravity Observations Of Hip 65426 B: Evidence For A Low Or Moderate Orbital Eccentricity, Sarah Blunt, W. O. Balmer, J. J. Wang, S. Lacour, S. Petrus, G. Bourdarot, J. Kammerer, N. Pourré, E. Rickman, J. Shangguan, T. Winterhalder, R. Abuter, A. Amorim, R. Asensio-Torres, M. Benisty, J. P. Berger, H. Beust, A. Boccaletti, A. Bohn, M. Bonnefoy, H. Bonnet, W. Brandner, F. Cantalloube, P. Caselli, B. Charnay, G. Chauvin, A. Chavez, E. Choquet, V. Christiaens, Y. Clénet, et al, Kimberly Ward-Duong 2023 Northwestern University

First Vlti/Gravity Observations Of Hip 65426 B: Evidence For A Low Or Moderate Orbital Eccentricity, Sarah Blunt, W. O. Balmer, J. J. Wang, S. Lacour, S. Petrus, G. Bourdarot, J. Kammerer, N. Pourré, E. Rickman, J. Shangguan, T. Winterhalder, R. Abuter, A. Amorim, R. Asensio-Torres, M. Benisty, J. P. Berger, H. Beust, A. Boccaletti, A. Bohn, M. Bonnefoy, H. Bonnet, W. Brandner, F. Cantalloube, P. Caselli, B. Charnay, G. Chauvin, A. Chavez, E. Choquet, V. Christiaens, Y. Clénet, Et Al, Kimberly Ward-Duong

Astronomy: Faculty Publications

Giant exoplanets have been directly imaged over orders of magnitude of orbital separations, prompting theoretical and observational investigations of their formation pathways. In this paper, we present new VLTI/GRAVITY astrometric data of HIP 65426 b, a cold, giant exoplanet which is a particular challenge for most formation theories at a projected separation of 92 au from its primary. Leveraging GRAVITY’s astrometric precision, we present an updated eccentricity posterior that disfavors large eccentricities. The eccentricity posterior is still prior dependent, and we extensively interpret and discuss the limits of the posterior constraints presented here. We also perform updated spectral comparisons with …


A Deeper Understanding Of The R Process, Mengke Li 2023 Clemson University

A Deeper Understanding Of The R Process, Mengke Li

All Dissertations

The overarching aim of my PhD research is to deepen our understanding of r-process nu- cleosynthesis. The initial phase of my work involved developing a Machine Learning-based nuclear mass model, specifically tailored to predict nuclear masses crucial for r-process nucleosynthesis. This model was then applied to simulate the r-process, focusing on neutron-rich nuclei significant to nucleosynthesis. The simulations yielded r-process abundance patterns, extending up to thorium and uranium, that align qualitatively with the observed solar system abundance patterns, with the characteristic peaks well positioned. Advancing our study further, we introduced a novel graph-based methodology named GrRproc for calculating r-process abundances. …


An Investigation Of The Accretion Processes In T Tauri And Herbig Ae/Be Systems Using High Resolution Optical And Near-Infrared Spectroscopy, Joshua Kern 2023 Clemson University

An Investigation Of The Accretion Processes In T Tauri And Herbig Ae/Be Systems Using High Resolution Optical And Near-Infrared Spectroscopy, Joshua Kern

All Dissertations

Star and planet formation is intimately tied to the accretion of material from the environments in which they form. During the formation process, disks of gas and dust develop in young stellar objects through which material is facilitated to the star and forming planets. Theoretical models of these accretion processes invoke viscous spreading via hydrodynamics, as well as more complex interactions with magnetic fields be it from the stellar component or the formation environment in order to catalyze these mass flows. These accretion models predict various scenarios including magnetospheric accretion as well as supersonic accretion flows in the disk atmosphere …


Godel, Escherian Staircase And Possibility Of Quantum Wormhole With Liquid Crystalline Phase Of Iced-Water - Part I: Theoretical Underpinning, Victor Christianto, T. Daniel Chandra, Florentin Smarandache 2023 University of New Mexico

Godel, Escherian Staircase And Possibility Of Quantum Wormhole With Liquid Crystalline Phase Of Iced-Water - Part I: Theoretical Underpinning, Victor Christianto, T. Daniel Chandra, Florentin Smarandache

Branch Mathematics and Statistics Faculty and Staff Publications

As a senior physicist colleague and our friend, Robert N. Boyd, wrote in a journal (JCFA, Vol. 1,. 2, 2022), Our universe is but one page in a large book [4]. For example, things and Beings can travel between Universes, intentionally or unintentionally. In this short remark, we revisit and offer short remark to Neil’s ideas and trying to connect them with geometrization of musical chords as presented by D. Tymoczko and others, then to Escher staircase and then to Jacob’s ladder which seems to point to possibility to interpret Jacob’s vision as described in the ancient book of Genesis …


Godel, Escherian Staircase And Possibility Of Quantum Wormhole With Liquid Crystalline Phase Of Iced-Water - Part Ii: Experiment Description, Victor Christianto, T. Daniel Chandra, Florentin Smarandache 2023 University of New Mexico

Godel, Escherian Staircase And Possibility Of Quantum Wormhole With Liquid Crystalline Phase Of Iced-Water - Part Ii: Experiment Description, Victor Christianto, T. Daniel Chandra, Florentin Smarandache

Branch Mathematics and Statistics Faculty and Staff Publications

The present article was partly inspired by G. Pollack’s book, and also Dadoloff, Saxena & Jensen (2010). As a senior physicist colleague and our friend, Robert N. Boyd, wrote in a journal (JCFA, Vol. 1, No. 2, 2022), for example, things and Beings can travel between Universes, intentionally or unintentionally [4]. In this short remark, we revisit and offer short remark to Neil Boyd’s ideas and trying to connect them with geometry of musical chords as presented by D. Tymoczko and others, then to Escherian staircase and then to Jacob’s ladder which seems to pointto possibility to interpret Jacob’s vision …


Cd-27°11535: Evidence For A Triple System In The Β Pictoris Moving Group, Andrew D. Thomas, Eric L. Nielsen, Robert J. De Rosa, Anne E. Peck, Bruce Macintosh, Jeffrey Chilcote, Paul Kalas, Jason J. Wang, Sarah Blunt, Alexandra Greenbaum, Quinn M. Konopacky, Michael J. Ireland, Peter Tuthill, Kimberly Ward-Duong, Lea A. Hirsch, Ian Czekala, Franck Marchis, Christian Marois, Max A. Millar-Blanchaer, William Roberson, Adam Smith, Hannah Gallamore, Jessica Klusmeyer 2023 Kavli Institute for Particle Astrophysics and Cosmology

Cd-27°11535: Evidence For A Triple System In The Β Pictoris Moving Group, Andrew D. Thomas, Eric L. Nielsen, Robert J. De Rosa, Anne E. Peck, Bruce Macintosh, Jeffrey Chilcote, Paul Kalas, Jason J. Wang, Sarah Blunt, Alexandra Greenbaum, Quinn M. Konopacky, Michael J. Ireland, Peter Tuthill, Kimberly Ward-Duong, Lea A. Hirsch, Ian Czekala, Franck Marchis, Christian Marois, Max A. Millar-Blanchaer, William Roberson, Adam Smith, Hannah Gallamore, Jessica Klusmeyer

Astronomy: Faculty Publications

We present new spatially resolved astrometry and photometry of the CD -27°11535 system, a member of the β Pictoris moving group consisting of two resolved K-type stars on a ∼20 yr orbit. We fit an orbit to relative astrometry measured from NIRC2, GPI, and archival NaCo images, in addition to literature measurements. However, the total mass inferred from this orbit is significantly discrepant from that inferred from stellar evolutionary models using the luminosity of the two stars. We explore two hypotheses that could explain this discrepant mass sum: a discrepant parallax measurement from Gaia due to variability, and the presence …


Temporal And Spectral Analysis Of 1es 2344+514 In Two Flaring States Observed By Veritas, Connor Poggemann 2023 California Polytechnic State University, San Luis Obispo

Temporal And Spectral Analysis Of 1es 2344+514 In Two Flaring States Observed By Veritas, Connor Poggemann

Physics

VERITAS observed the bright blazar 1ES 2344+514 during two flaring periods, one from Dec. 17 to Dec. 18, 2015 (MJD 57373-57374) with a peak flux of ~60% of the Crab and another from Nov. 28 to Dec. 3, 2021 (MJD 59546-59551) with a peak flux of ~20% of the Crab. This blazar, located at a redshift of z = 0.044, is classified as an extreme high-frequency-peaked BL Lacertae object (HBL). It is known to be variable, including several previous day-scale flares: Whipple on Dec. 20, 1995, VERITAS on Dec. 7, 2007, and MAGIC on Aug. 11, 2016. The VERITAS near-nightly …


Teaching Introductory Physics In The Context Of Personal And Societal Issues Of The Covid-19 Pandemic, Guang Zeng, Liang Zeng 2023 Texas A&M University-Corpus Christi

Teaching Introductory Physics In The Context Of Personal And Societal Issues Of The Covid-19 Pandemic, Guang Zeng, Liang Zeng

Physics & Astronomy Faculty Publications

This paper reports on introductory physics instruction contextualized in terms of coronavirus-related personal and societal issues. Students in this descriptive qualitative study gained a strong grasp of a range of physics concepts associated with the nature and mechanisms of the spread of the coronavirus, such as projectile motion, air convection, Reynolds number, and Brownian motion; additionally, they were able to discuss the application of physics relevant to the N95 face masks. Students found this pedagogical approach engaging, as shown in their reflective writing.


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