Optimization Of Orbital Trajectories Using Neuroevolution Of Augmenting Topologies,
2022
University of Connecticut
Optimization Of Orbital Trajectories Using Neuroevolution Of Augmenting Topologies, Nathan Wetherell
University Scholar Projects
This project aims to determine the feasibility of using NeuroEvolution of Augmenting Topologies (NEAT), an advanced neural network evolution scheme, to optimize orbital transfer trajectories. More specifically, this project compares a genetically evolved neural network to a standard Hohmann transfer between Earth and Mars. To test these two methods, an N-body simulation environment was created to accurately determine the result of gravitational interactions on a theoretical spacecraft when combined with planned engine burns. Once created, this simulation environment was used to train the neural networks created using the NEAT Python module. A genetic algorithm was used to modify the topology …
First Test Of Lepton Flavor Universality In The Charmed Baryon Decays Ωc0 → Ω-ℓ+Νℓ Using Data Of The Belle Experiment,
2022
Fudan University
First Test Of Lepton Flavor Universality In The Charmed Baryon Decays Ωc0 → Ω-ℓ+Νℓ Using Data Of The Belle Experiment, Y. B. Li, C. P. Shen, I. Adachi, H. Aihara, S. Al Said, D. M. Asner, H. Atmacan, T. Aushev, R. Ayad, V. Babu, S. Bahinipati, P. Behera, K. Belous, J. Bennett, F. Bernlochner, M. Bessner, B. Bhuyan, T. Bilka, A. Bobrov
Faculty and Student Publications
We present the first observation of the ωc0→ω-μ+νμ decay and present measurements of the branching fraction ratios of the ωc0→ω-ℓ+νℓ decays compared to the reference mode ωc0→ω-π+, (ℓ=e or μ). This analysis is based on 89.5 fb-1, 711 fb-1, and 121.1 fb-1 data samples collected with the Belle detector at the KEKB asymmetric-energy e+e- collider at the center-of-mass energies of 10.52 GeV, 10.58 GeV, and 10.86 GeV, respectively. The ωc0 signal yields are extracted by fitting Mωℓ and Mωπ spectra. The branching fraction ratios B(ωc0→ω-e+νe)/B(ωc0→ω-π+) and B(ωc0→ω-μ+νμ)/B(ωc0→ω-π+) are measured to be 1.98±0.13(stat)±0.08(syst) and 1.94±0.18(stat)±0.10(syst), respectively. The ratio of B(ωc0→ω-e+νe)/B(ωc0→ω-μ+νμ) is …
Monitoring The M-Dwarf Host Stars Of Tess Exoplanet Candidates: Stellar Flares And Habitability,
2022
University of Arkansas, Fayetteville
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 …
Search For Charged Lepton Flavor Violating Decays Of ϒ (1s),
2022
Indian Institute of Science Education and Research Mohali
Search For Charged Lepton Flavor Violating Decays Of ϒ (1s), S. Patra, V. Bhardwaj, K. Trabelsi, I. Adachi, H. Aihara, S. Al Said, D. M. Asner, H. Atmacan, T. Aushev, R. Ayad, V. Babu, S. Bahinipati, P. Behera, K. Belous, J. Bennett, M. Bessner, B. Bhuyan, T. Bilka, A. Bobrov
Faculty and Student Publications
We present a search for the charged lepton-flavor-violating decays ϒ(1S) →ℓ±ℓ′∓ and radiative charged lepton-flavour-violating decays ϒ(1S) → γℓ±ℓ′∓ [ℓ,ℓ′ = e, μ, τ] using the 158 million ϒ(2S) sample collected by the Belle detector at the KEKB collider. This search uses ϒ(1S) mesons produced in ϒ(2S) → π+π− ϒ(1S) transitions. We do not find any significant signal, so we provide upper limits on the branching fractions at the 90% confidence level. [Figure not available: see fulltext.]
Emergent Spectra Of Young X-Ray Emitting Populations Across Environments,
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).
A Possible Alignment Between The Orbits Of Planetary Systems And Their Visual Binary Companions,
2022
Swarthmore College
A Possible Alignment Between The Orbits Of Planetary Systems And Their Visual Binary Companions, S. Christian, A. Vanderburg, J. Becker, D. A. Yahalomi, L. Pearce, G. Zhou, K. A. Collins, A. L. Kraus, K. G. Stassun, Z. De Beurs, G. R. Ricker, R. K. Vanderspek, D. W. Latham, J. N. Winn, S. Seager, J. M. Jenkins, L. Abe, K. Agabi, P. J. Amado, D. Baker, K. Barkaoui, Z. Benkhaldoun, P. Benni, J. Berberian, P. Berlind, A. Bieryla, E. Esparza-Borges, M. Bowen, P. Brown, L. A. Buchhave, C. J. Burke, M. Buttu, C. Cadieux, D. A. Caldwell, D. Charbonneau, N. Chazov, S. Chimaladinne, K. I. Collins, D. Combs, D. M. Conti, N. Crouzet, J. P. De Leon, S. Deljookorani, B. Diamond, R. Doyon, D. Dragomir, G. Dransfield, Z. Essack, P. Evans, A. Fukui, T. Gan, G. A. Esquerdo, M. Gillon, E. Girardin, P. Guerra, T. Guillot, E. K. K. Habich, A. Henriksen, N. Hoch, K. I. Isogai, E. Jehin, Eric L.N. Jensen, M. C. Johnson, J. H. Livingston, J. F. Kielkopf, K. Kim, K. Kawauchi, V. Krushinsky, V. Kunzle, D. Laloum, D. Leger, P. Lewin, F. Mallia, B. Massey, M. Mori, K. K. Mcleod, D. Mékarnia, I. Mireles, N. Mishevskiy, M. Tamura, F. Murgas, N. Narita, R. Naves, P. Nelson, H. P. Osborn, E. Palle, H. Parviainen, P. Plavchan, F. J. Pozuelos, M. Rabus, H. M. Relles, C. Rodríguez López, S. N. Quinn, F.-X. Schmider, J. E. Schlieder, R. P. Schwarz, A. Shporer, L. Sibbald, G. Srdoc, C. Stibbards, H. Stickler, O. Suarez, C. Stockdale, T.-G. Tan, Y. Terada, A. Triaud, R. Tronsgaard, W. C. Waalkes, G. Wang, N. Watanabe, M.-S. Wenceslas, G. Wingham, J. Wittrock, C. Ziegler
Physics & Astronomy Faculty Works
Astronomers do not have a complete picture of the effects of wide-binary companions (semimajor axes greater than 100 au) on the formation and evolution of exoplanets. We investigate these effects using new data from Gaia Early Data Release 3 and the Transiting Exoplanet Survey Satellite mission to characterize wide-binary systems with transiting exoplanets. We identify a sample of 67 systems of transiting exoplanet candidates (with well-determined, edge-on orbital inclinations) that reside in wide visual binary systems. We derive limits on orbital parameters for the wide-binary systems and measure the minimum difference in orbital inclination between the binary and planet orbits. …
Chandra Spectral Constraints Of The Low-Metallicity Collision Ring Cartwheel Galaxy,
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 …
Reinforcement Learning In A Quantum Network,
2022
Louisiana State University
Reinforcement Learning In A Quantum Network, Roy Pace
Honors Capstones
No abstract provided.
The Dense Gas Mass Fraction And The Relationship To Star Formation In M51,
2022
University of Massachusetts Amherst
The Dense Gas Mass Fraction And The Relationship To Star Formation In M51, Mark Heyer, Benjamin Gregg, Daniela Calzetti, Bruce G. Elmegreen, Robert Kennicutt, Angela Adamo, Aaron S. Evans, Kathryn Grasha, James D. Lowenthal, Gopal Narayanan, Daniel Rosa-Gonzalez, F. P. Schloerb, Kamal Souccar, Yuping Tang, Peter Teuben, Olga Vega, William F. Wall, Min S. Yun
Astronomy: Faculty Publications
Observations of 12CO J = 1 - 0 and HCN J = 1 - 0 emission from NGC 5194 (M51) made with the 50 m Large Millimeter Telescope and the SEQUOIA focal plane array are presented. Using the HCN-to-CO ratio, we examine the dense gas mass fraction over a range of environmental conditions within the galaxy. Within the disk, the dense gas mass fraction varies along the spiral arms but the average value over all spiral arms is comparable to the mean value of interarm regions. We suggest that the near-constant dense gas mass fraction throughout the disk arises from …
Alma Discovery Of A Disk Around The Planetary-Mass Companion Sr 12 C,
2022
National Taiwan Normal University
Alma Discovery Of A Disk Around The Planetary-Mass Companion Sr 12 C, Ya Lin Wu, Brendan P. Bowler, Patrick D. Sheehan, Laird M. Close, Joshua A. Eisner, William M.J. Best, Kimberly Ward-Duong, Zhaohuan Zhu, Adam L. Kraus
Astronomy: Faculty Publications
We report an Atacama Large Millimeter/submillimeter Array 0.88 mm (Band 7) continuum detection of the accretion disk around SR 12 c, an ∼11 M Jup planetary-mass companion (PMC) orbiting its host binary at 980 au. This is the first submillimeter detection of a circumplanetary disk around a wide PMC. The disk has a flux density of 127 ± 14 μJy and is not resolved by the ∼0.″1 beam, so the dust disk radius is likely less than 5 au and can be much smaller if the dust continuum is optically thick. If, however, the dust emission is optically thin, then …
Signal Yields And Detector Modeling In Xenon Time Projection Chambers, And Results Of An Effective Field Theory Dark Matter Search Using Lux Data,
2022
University at Albany, State University of New York
Signal Yields And Detector Modeling In Xenon Time Projection Chambers, And Results Of An Effective Field Theory Dark Matter Search Using Lux Data, Gregory Ransford Carl Rischbieter
Legacy Theses & Dissertations (2009 - 2024)
The nature of dark matter continues to be one of the biggest remaining mysteries in physics. Astrophysical measurements indicate that dark matter makes up more than a quarter of the Universe's total energy density, and it is well-motivated that dark matter is comprised of Weakly Interacting Massive Particles (WIMPs). Direct detection techniques utilizing liquid and gaseous noble elements have become the primary method of probing the potential non-gravitational interactions between WIMPs and Standard Model matter, with the leading technology being the dual-phase Time Projection Chamber (TPC). The Large Underground Xenon (LUX) and its second-generation successor, LUX-ZEPLIN (LZ), are two xenon …
The Majorana Demonstrator Readout Electronics System,
2022
University of South Carolina
The Majorana Demonstrator Readout Electronics System, N. Abgrall, M. Amman, I. J. Arnquist, Frank Avignone Iii, A. S. Barabash, C. J. Barton, P. J. Barton, F. E. Bertrand, K. H. Bhimani, B. Bos, A. W. Bradley, T. H. Burritt, M. Busch, M. Buuck, T. S. Caldwell, Y-D. Chan, C. D. Christofferson, P.-H. Chu, M. L. Clark, R. J. Cooper, C. Cuesta, Et. Al.
Faculty Publications
The Majorana Demonstrator comprises two arrays of high-purity germanium detectors constructed to search for neutrinoless double-beta decay in 76Ge and other physics beyond the Standard Model. Its readout electronics were designed to have low electronic noise, and radioactive backgrounds were minimized by using low-mass components and low-radioactivity materials near the detectors. This paper provides a description of all components of the Majorana Demonstrator readout electronics, spanning the front-end electronics and internal cabling, back-end electronics, digitizer, and power supplies, along with the grounding scheme. The spectroscopic performance achieved with these readout electronics is also demonstrated.
Elevated Hot Gas And High-Mass X-Ray Binary Emission In Low-Metallicity Galaxies: Implications For Nebular Ionization And Intergalactic Medium Heating In The Early Universe,
2022
University of Arkansas, Fayetteville
Elevated Hot Gas And High-Mass X-Ray Binary Emission In Low-Metallicity Galaxies: Implications For Nebular Ionization And Intergalactic Medium Heating In The Early Universe, Bret D. Lehmer, Rafael T. Eufrasio, Antara Basu-Zych, Kristen Garofali, Woodrow Gilbertson, Andrei Mesinger, Mihoko Yukita
Space and Planetary Science Faculty Publications and Presentations
High-energy emission associated with star formation has been proposed as a significant source of interstellar medium (ISM) ionization in low-metallicity starbursts and an important contributor to the heating of the intergalactic medium (IGM) in the high-redshift (z ≳ 8) universe. Using Chandra observations of a sample of 30 galaxies at D ≈ 200–450 Mpc that have high specific star formation rates of 3–9 Gyr−1 and metallicities near Z ≈ 0.3Z⊙, we provide new measurements of the average 0.5–8 keV spectral shape and normalization per unit star formation rate (SFR). We model the sample-combined X-ray spectrum as a …
Dust-Gas Dynamics Driven By The Streaming Instability With Various Pressure Gradients,
2022
University of Nevada, Las Vegas
Dust-Gas Dynamics Driven By The Streaming Instability With Various Pressure Gradients, Stanley Antedio Baronett
UNLV Theses, Dissertations, Professional Papers, and Capstones
The radial pressure gradient (RPG), along the midplane of gaseous protoplanetary disks (PPD) – planetary nurseries – poses a severe obstacle to planet formation. Micron-sized dust grains, embedded in the disc, must quickly grow to kilometer-sized planetesimals – the building blocks of planets – before fatally drifting inwards, by RPG-induced gas drag, into a central host star. However, the RPG simultaneously powers one of the most robust processes to overcome this radial-drift barrier: the streaming instability (SI). Spontaneously triggered, the SI aerodynamically concentrates drifting dust via drag-induced, coupled interactions and feedback with the surrounding gas. In particular, the non-linear phase …
Using Nasa's Tess Mission To Search For Extremely Low Mass White Dwarf Stars,
2022
Butler University
Using Nasa's Tess Mission To Search For Extremely Low Mass White Dwarf Stars, Corinna Peña
Undergraduate Honors Thesis Collection
Extremely low-mass white dwarf stars (ELM) are white dwarf stars with a mass lower than 0.45 solar masses that could not have evolved through normal processes within the lifetime of our universe. Therefore, these objects can only be created through a common envelope phase or a stable Roche lobe overflow while in a binary. These objects have periods between a few minutes to a few hours, so they are very short lived which makes them very rare. My goal for this project was to find these ELM stars by using NASA's Transiting Exoplanet Survey Satellite (TESS) data. I analyzed this …
Electromagnetic Detectability Of Binary Supermassive Black Holes,
2022
University of Connecticut
Electromagnetic Detectability Of Binary Supermassive Black Holes, Kaylee Grace
Honors Scholar Theses
Supermassive black hole (SMBH) binaries can be produced by galaxy mergers and are important sources of gravitational waves. Although several binary candidates have been identified in previous work, none have yet been fully confirmed. These pairs are difficult to detect, since single accreting SMBHs can have pseudo-periodic lightcurves due to stochastic noise that can mimic the signature of binary SMBHs. The aforementioned lightcurves are the detections we classify as ”false-positive.” The Vera Rubin Observatory (VRO) will be a powerful new tool for detecting binary SMBHs. We determine the false-positive binary detection rate for VRO by attempting to recover sinusoidal binary …
The Impact Of Inclination-Dependent Attenuation On Ultraviolet Star Formation Rate Tracers,
2022
University of Arkansas, Fayetteville
The Impact Of Inclination-Dependent Attenuation On Ultraviolet Star Formation Rate Tracers, Keith Doore, Rafael T. Eufrasio, Bret D. Lehmer, Erik B. Monson, Antara Basu-Zych, Kristen Garofali
Physics Faculty Publications and Presentations
We examine and quantify how hybrid (e.g., UV+IR) star formation rate (SFR) estimators and the AFUV–β relation depend on inclination for disk-dominated galaxies using spectral energy distribution modeling that utilizes the inclination-dependent attenuation curves described in Doore et al. We perform this analysis on a sample of 133 disk-dominated galaxies from the CANDELS fields and 18 disk galaxies from the Spitzer Infrared Nearby Galaxies Survey and Key Insights on Nearby Galaxies: A Far-Infrared Survey with Herschel samples. We find that both the hybrid SFR estimators and the AFUV–β relation present clear dependencies on inclination. To quantify …
A Monte Carlo Method For Evaluating Empirical Gyrochronology Models And Its Application To Wide Binary Benchmarks,
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.
Exploring The Glow Of The Universe In Gamma-Rays And Hunting Distant Agn,
2022
Clemson University
Exploring The Glow Of The Universe In Gamma-Rays And Hunting Distant Agn, Changam Meenakshi Rajagopal
All Dissertations
The entirety of the γ-ray radiation permeating our Universe is encoded in the extragalactic γ-ray background. This is a superposition of resolved sources, mostly powerful relativistic jets powered by supermassive black holes, i.e., blazars, and an unresolved isotropic component, aka, the diffuse isotropic gamma-ray background (IGRB). Studying the IGRB can help unveil its composition, as well as unearth multi-messenger relationships between the intensities of PeV neutrinos, ultra high energy cosmic rays (> 1018 eV), and sub-TeV γ-rays. The comparable energy budgets of these three phenomena (neutrinos, UHECR, and γ-rays) indicates a physical connection or a common source amongst them. On …
Physics Of Electromagnetic Counterparts Of Binary-Neutron-Star Mergers,
2022
University of Nevada, Las Vegas
Physics Of Electromagnetic Counterparts Of Binary-Neutron-Star Mergers, Shunke Ai
UNLV Theses, Dissertations, Professional Papers, and Capstones
Binary neutron star (BNS) mergers are supposed to be the sources of a variety of astrophysical transients, including both gravitational wave (GW) and electromagnetic (EM) signals. The types and properties of the post-merger central product contain crucial information for many unsolved physical problems. Since the current GW detectors are not sensitive enough in kHz, only GWs from the inspiral phase can be detected, so that one cannot directly study the central products from GWs. EM signals can serve as probes to infer the type and properties of the central product. When a long-lived neutron star (NS) is formed after the …
