The Loneliest Galaxies In The Universe: A Gama And Galaxy Zoo Study On Void Galaxy Morphology.,
2023
University of Louisville
The Loneliest Galaxies In The Universe: A Gama And Galaxy Zoo Study On Void Galaxy Morphology., Lori E. Porter
College of Arts & Sciences Senior Honors Theses
The large-scale structure (LSS) of the Universe is comprised of galaxy filaments, tendrils, and voids. The majority of the Universe’s volume is taken up by these voids, which exist as underdense, but not empty, regions. The galaxies found inside voids are void galaxies and expected to be some of the most isolated objects in the Universe. However, their standard morphology remains poorly studied. This study, using the Galaxy and Mass Assembly (GAMA) data and Galaxy Zoo survey, aims to remedy this. For completeness purposes, we use void galaxies identified by Alpaslan et al. (2014) with stellar masses (M*) of 10 …
Wallaby Pilot Survey: H I Gas Kinematics Of Galaxy Pairs In Cluster Environment,
2023
The University of Texas Rio Grande Valley
Wallaby Pilot Survey: H I Gas Kinematics Of Galaxy Pairs In Cluster Environment, Shin-Jeong Kim, Se-Heon Oh, Jing Wang, Lister Staveley-Smith, Bärbel S. Koribalski, Minsu Kim, Hye-Jin Park, Shinna Kim, Kristine Spekkens, Juan P. Madrid
Physics and Astronomy Faculty Publications and Presentations
We examine the H I gas kinematics of galaxy pairs in two clusters and a group using Australian Square Kilometre Array Pathfinder (ASKAP) WALLABY pilot survey observations. We compare the H I properties of galaxy pair candidates in the Hydra I and Norma clusters, and the NGC 4636 group, with those of non-paired control galaxies selected in the same fields. We perform H I profile decomposition of the sample galaxies using a tool, BAYGAUD, which allows us to deblend a line-of-sight velocity profile with an optimal number of Gaussian components. We construct H I superprofiles of the sample galaxies via …
Table Of Contents,
2023
University of South Carolina
Table Of Contents
Journal of the South Carolina Academy of Science
No abstract provided.
Glitch Subtraction From Gravitational Wave Data Using Adaptive Spline Fitting,
2023
The University of Texas Rio Grande Valley
Glitch Subtraction From Gravitational Wave Data Using Adaptive Spline Fitting, Soumya Mohanty, Mohammad A. T. Chowdhury
Physics and Astronomy Faculty Publications and Presentations
Transient signals of instrumental and environmental origins ("glitches") in gravitational wave data elevate the false alarm rate of searches for astrophysical signals and reduce their sensitivity. Glitches that directly overlap astrophysical signals hinder their detection and worsen parameter estimation errors. As the fraction of data occupied by detectable astrophysical signals will be higher in next generation detectors, such problematic overlaps could become more frequent. These adverse effects of glitches can be mitigated by estimating and subtracting them out from the data, but their unpredictable waveforms and large morphological diversity pose a challenge. Subtraction of glitches using data from auxiliary sensors …
Measurement Of Near-Threshold Proton Branching Ratios In 31s Important For Novae,
2023
Louisiana State University
Measurement Of Near-Threshold Proton Branching Ratios In 31s Important For Novae, Sudarsan Balakrishnan
LSU Doctoral Dissertations
Classical novae are stellar explosions that contribute to the nucleosynthesis of isotopes on the proton-rich side of the valley of stability up to 40Ca. In ONe novae, the incompletely understood reaction rate of 30P(p,γ)31S is known to strongly influence the production rate of several stable isotopes such as 30Si, 31P, and 32,33,34S. A precise measurement of this reaction rate has several potential implications towards matching astrophysical observables to the physical composition of the nova site -- the observed elemental abundance ratios of O/S and S/Al have been suggested as useful `thermometers' to gauge …
Effects Of Silicon Dioxide As The Polar Dielectric On The Infrared Absorption Spectrum Ofthemetal-Insulator-Metal Metasurface,
2023
Texas Tech University
Effects Of Silicon Dioxide As The Polar Dielectric On The Infrared Absorption Spectrum Ofthemetal-Insulator-Metal Metasurface, Ahmad K. Jafari, Matthew Gaddy, Imtiaz Ahmad, Satya R. Kachiraju, M D. Borhan Mia, Ishtiaque Ahmed, Sergey Nikishin, Myoung-Hwan Kim, Ayrton A. Bernussi
Physics and Astronomy Faculty Publications and Presentations
Metal-insulator-metal metasurfaces have been widely used as high-performance absorbers in almost all electromagnetic spectral ranges. Their absorption spectra can be engineered by making variations in the geometry of the unit cells and/or by embedding materials with specific optical constants. Including a polar dielectric in their structure is another approach for manipulating their absorption spectra. In this research, we have numerically and experimentally investigated the effect of using silicon dioxide (SiO2) as a polar dielectric on the absorption spectrum of a metal-insulator-metal metasurface composed of a tri-layer of Ni-SiO2-Ni. Our results have shown the presence of …
Search For Subsolar-Mass Black Hole Binaries In The Second Part Of Advanced Ligo’S And Advanced Virgo’S Third Observing Run,
2023
The University of Texas Rio Grande Valley
Search For Subsolar-Mass Black Hole Binaries In The Second Part Of Advanced Ligo’S And Advanced Virgo’S Third Observing Run, R. Abbott, H. Abe, F. Acernese, Teviet Creighton, Mario C. Diaz, Francisco Llamas, Soma Mukherjee, Gaukhar Nurbek, Volker Quetschke, Wenhui Wang
Physics and Astronomy Faculty Publications and Presentations
We describe a search for gravitational waves from compact binaries with at least one component with mass 0.2 M⊙ -- 1.0M⊙ and mass ratio q≥0.1 in Advanced LIGO and Advanced Virgo data collected between 1 November 2019, 15:00 UTC and 27 March 2020, 17:00 UTC. No signals were detected. The most significant candidate has a false alarm rate of 0.2 yr−1. We estimate the sensitivity of our search over the entirety of Advanced LIGO's and Advanced Virgo's third observing run, and present the most stringent limits to date on the merger rate of binary black holes with at least one …
Helioseismic Diagnostics Of Active Regions And Their Magnetic Fields,
2022
New Jersey Institute of Technology
Helioseismic Diagnostics Of Active Regions And Their Magnetic Fields, John T. Stefan
Dissertations
While two and a half decades of nearly constant observation by the Solar and Heliospheric Observatory (SOHO) and the Solar Dynamics Observatory (SDO) spacecraft have yielded key insights into the structure and dynamics of active regions, it is still unclear if active regions can be identified before emerging on the solar surface and, once emerged, whether the subsurface structure of an active region’s magnetic field can be measured. Regarding the dynamical processes associated with active regions, the height and mechanism of sunquake excitation remains poorly understood. To answer these questions, a comprehensive survey of active region magnetic fields and their …
Model-Based Cross-Correlation Search For Gravitational Waves From The Low-Mass X-Ray Binary Scorpius X-1 In Ligo O3 Data,
2022
The University of Texas Rio Grande Valley
Model-Based Cross-Correlation Search For Gravitational Waves From The Low-Mass X-Ray Binary Scorpius X-1 In Ligo O3 Data, R. Abbott, H. Abe, Fausto Acernese, Teviet Creighton, Mario C. Diaz, Francisco Llamas, Soma Mukherjee, Gaukhar Nurbek, Volker Quetschke, Wenhui Wang
Physics and Astronomy Faculty Publications and Presentations
We present the results of a model-based search for continuous gravitational waves from the low-mass X-ray binary Scorpius X-1 using LIGO detector data from the third observing run of Advanced LIGO and Advanced Virgo. This is a semicoherent search that uses details of the signal model to coherently combine data separated by less than a specified coherence time, which can be adjusted to balance sensitivity with computing cost. The search covered a range of gravitational-wave frequencies from 25 to 1600 Hz, as well as ranges in orbital speed, frequency, and phase determined from observational constraints. No significant detection candidates were …
Galaxy And Mass Assembly (Gama): The Dependence Of Star Formation On Surface Brightness In Low-Redshift Galaxies,
2022
University of Louisville
Galaxy And Mass Assembly (Gama): The Dependence Of Star Formation On Surface Brightness In Low-Redshift Galaxies, S Phillipps, S Bellstedt, M N. Bremer, R De Propris, P A. James, S Casura, J Liske, B W. Holwerda
Faculty Scholarship
The star-formation rate in galaxies is well known to correlate with stellar mass (the ‘star-forming main sequence’). Here, we extend this further to explore any additional dependence on galaxy surface brightness, a proxy for stellar mass surface density. We use a large sample of low-redshift (z ≤ 0.08) galaxies from the Galaxy And Mass Assembly survey which have both spectral energy distribution (SED) derived star-formation rates and photometric bulge-disc decompositions, the latter providing measures of disc surface brightness and disc masses. Using two samples, one of galaxies fitted by a single component with Sérsic index below 2 and one …
Multifrequency Scintillation In The Polar Caps,
2022
Embry-Riddle Aeronautical University
Multifrequency Scintillation In The Polar Caps, Tate Colby
Doctoral Dissertations and Master's Theses
In the ionosphere, plasma density structures with scales sizes ranging from a few centimeters to hundreds of kilometers are capable of modifying the phase and amplitude of a radio signal in a rapid random manner in a process called scintillation. The Coherent Electromagnetic Radio Tomography (CERTO) and the Canadian High Arctic Ionospheric Network (CHAIN) are two different networks of scintillation receivers, each with a station in Resolute Bay, Canada. CERTO measures amplitude and phase signals in VHF and UHF while CHAIN measures amplitude and phase signals in the L-band. Through these measurements we can calculate the scintillation indexes, S_4 and …
Non-Hermitian Edge Burst Without Skin Localizations,
2022
The University of Texas Rio Grande Valley
Non-Hermitian Edge Burst Without Skin Localizations, Cem Yuce, H. Ramezani
Physics and Astronomy Faculty Publications and Presentations
In a class of non-Hermitian quantum walk in lossy lattices with open boundary conditions, an unexpected peak in the distribution of the decay probabilities appears at the edge, dubbed edge burst. It is proposed that the edge burst is originated jointly from the non-Hermitian skin effect (NHSE) and the imaginary gaplessness of the spectrum [Wen-Tan Xue et al., Phys. Rev. Lett. 128, 120401 (2022)]. Using a particular one-dimensional lossy lattice with a nonuniform loss rate, we show that the edge burst can occur even in the absence of NHSE. Furthermore, we discuss that the edge burst may not appear if …
The Planets, Reimagined: Translating Science Into Music,
2022
Bowling Green State University
The Planets, Reimagined: Translating Science Into Music, Kaitlyn Wincup
Honors Projects
Inspired by Gustav Holst’s The Planets, this project analyzed the qualitative properties of the planets in our Solar System and translated them into a composition, created by Connor Gibbs, to represent an overall aural depiction of each planet. Where Holst created an astrological depiction of each of the planets, this piece is an astronomical depiction that broadens the perspectives of its listeners.
Stabilization Of Zero-Energy Skin Modes In Finite Non-Hermitian Lattices,
2022
The University of Texas Rio Grande Valley
Stabilization Of Zero-Energy Skin Modes In Finite Non-Hermitian Lattices, Cem Yuce, Hamidreza Ramezani
Physics and Astronomy Faculty Publications and Presentations
The zero energy of a one-dimensional semi-infinite non-Hermitian lattice with nontrivial spectral topology may disappear when we introduce boundaries to the system. While the corresponding zero-energy state can be considered as a quasi-edge state for the finite lattice with a long survival time, any small disruption (noise) in the initial form of the quasi-edge state can significantly shorten the survival time. Here, by tailoring the couplings at one edge we form an exceptional point allowing for a topological phase transition and the stabilization of the quasi-edge state in a finite-size lattice with open edges. Such a small modification in the …
Core-Collapse Supernova Simulations With Spectral Two-Moment Neutrino Transport,
2022
University of Tennessee, Knoxville
Core-Collapse Supernova Simulations With Spectral Two-Moment Neutrino Transport, Ran Chu
Doctoral Dissertations
The primary focus of this dissertation is to develop a next-generation, state-of-the-art neutrino kinetics capability that will be used in the context of the next-generation, state-of-the-art core-collapse supernova (CCSN) simulation frameworks \thornado\ and \FLASH.\index{CCSN} \thornado\ is a \textbf{t}oolkit for \textbf{h}igh-\textbf{or}der \textbf{n}eutrino-r\textbf{ad}iation hydr\textbf{o}dynamics, which is a collection of modules that can be incorporated into a simulation code/framework, such as \FLASH, together with a nuclear equation of state (EOS)\index{EOS} library, such as the \WeakLib\ EOS tables. The first part of this work extends the \WeakLib\ code to compute neutrino interaction rates from~\cite{Bruenn_1985} and produce corresponding opacity tables.\index{Bruenn 1985} The processes of emission, …
Weak Gravitational Lensing Analysis In Two Superclusters Of Galaxies,
2022
University of Maine
Weak Gravitational Lensing Analysis In Two Superclusters Of Galaxies, Sarah B. Rice
Electronic Theses and Dissertations
Observations of the Universe on very large scales have shown it to be filled with galaxy clusters and superclusters connected by walls and filaments of galaxies, with vast areas mostly devoid of luminous matter separating them. It is widely accepted that the amount of luminous matter does not provide the mass needed to hold galaxies and galaxy clusters together, and the nature of the missing "dark matter" is one of the most prominent astrophysical mysteries today. Since dark matter interacts with luminous matter gravitationally, it stands to reason that dark matter might organize itself in a similar manner to luminous …
Dataset For Electronic And Optical Properties Of Y2o2s And Er Dopped Y2o2s Calculated Using Density Functional Theory And Simulated X-Ray Near Edge Spectra,
2022
The University of Texas Rio Grande Valley
Dataset For Electronic And Optical Properties Of Y2o2s And Er Dopped Y2o2s Calculated Using Density Functional Theory And Simulated X-Ray Near Edge Spectra, N. Dimakis, Eric Baldemar Rodriguez Jr., Kofi Nketia Ackaah-Gyasi, Madhab Pokhrel
Physics and Astronomy Faculty Publications and Presentations
The computational data presented in this paper refer to the research article “Optical properties and simulated x-ray near edge spectra for Y2O2S and Er doped Y2O2S”. We present the data used to calculate the structural, electronic, and optical properties of the Y2O2S and its Er+3 doped counterparts at various concentrations using density functional theory (DFT) and simulated X-ray near edge (XANES) spectra. We report electronic information from DFT and DFT+U generated from the Vienna Ab initio Simulation Package (VASP) using PAW pseudopotentials. We also report VASP calculated optical properties for the host Y2O2S using the independent particle approximation (IPA), the …
Investigating The O’Connell Effect In Kepler Eclipsing Binaries,
2022
Florida Institute of Technology
Investigating The O’Connell Effect In Kepler Eclipsing Binaries, Matthew Frederick Knote
Theses and Dissertations
The O’Connell effect – the presence of unequal maxima in eclipsing binaries – remains an unsolved riddle in the study of close binary systems. The Kepler space telescope produced high precision photometry of nearly 3,000 eclipsing binary systems, providing a unique opportunity to study the O’Connell effect in a large sample and in greater detail than in previous studies. I have characterized the observational properties – including temperature, luminosity, and eclipse depth – of a set of 212 systems (7.3% of Kepler eclipsing binaries) that display a maxima flux difference of at least 1%, representing the largest sample of O’Connell …
All-Sky Search For Continuous Gravitational Waves From Isolated Neutron Stars Using Advanced Ligo And Advanced Virgo O3 Data,
2022
The University of Texas Rio Grande Valley
All-Sky Search For Continuous Gravitational Waves From Isolated Neutron Stars Using Advanced Ligo And Advanced Virgo O3 Data, R. Abbott, H. Abe, M. G. Benjamin, Teviet Creighton, Mario C. Diaz, Francisco Llamas, Soma Mukherjee, Gaukhar Nurbek, Volker Quetschke, Wenhui Wang
Physics and Astronomy Faculty Publications and Presentations
We present results of an all-sky search for continuous gravitational waves which can be produced by spinning neutron stars with an asymmetry around their rotation axis, using data from the third observing run of the Advanced LIGO and Advanced Virgo detectors. Four different analysis methods are used to search in a gravitational-wave frequency band from 10 to 2048 Hz and a first frequency derivative from −10−8 to 10−9 Hz/s. No statistically significant periodic gravitational-wave signal is observed by any of the four searches. As a result, upper limits on the gravitational-wave strain amplitude h0 are calculated. The best upper limits …
Galaxy And Mass Assembly (Gama): Extended Intragroup Light In A Group At Z = 0.2 From Deep Hyper Suprime-Cam Images,
2022
University of Louisville
Galaxy And Mass Assembly (Gama): Extended Intragroup Light In A Group At Z = 0.2 From Deep Hyper Suprime-Cam Images, Cristina Martínez-Lombilla, Sarah Brough, Mireia Montes, Roberto Baena-Gallé, Mohammad Akhlaghi, Raúl Infante-Sainz, Simon P. Driver, Benne W. Holwerda, Kevin A. Pimbblet, Aaron S G Robotham
Faculty Scholarship
We present a pilot study to assess the potential of Hyper Suprime-Cam Public Data Release 2 (HSC-PDR2) images for the analysis of extended faint structures within groups of galaxies. We examine the intragroup light (IGL) of the group 400138 (Mdyn = 1.3 ± 0.5 × 1013 M⊙, z ∼ 0.2) from the Galaxy And Mass Assembly (GAMA) survey using Hyper Suprime-Cam Subaru Strategic Program Public Data Release 2 (HSC-SSP PDR2) images in g, r, and i bands. We present the most extended IGL measurement to date, reaching down to μglim=30.76" role="presentation" style="box-sizing: border-box; margin: 0px; …
