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Approximate Solutions Of Nonlinear Partial Differential Equations Using B-Polynomial Bases, Muhammad I. Bhatti, Md. Habibur Rahman, Nicholas Dimakis 2021 The University of Texas Rio Grande Valley

Approximate Solutions Of Nonlinear Partial Differential Equations Using B-Polynomial Bases, Muhammad I. Bhatti, Md. Habibur Rahman, Nicholas Dimakis

Physics & Astronomy Faculty Publications

A multivariable technique has been incorporated for guesstimating solutions of Nonlinear Partial Differential Equations (NPDE) using bases set of B-Polynomials (B-polys). To approximate the anticipated solution of the NPD equation, a linear product of variable coefficients ai(t) and Bi(x) B-polys has been employed. Additionally, the variable quantities in the anticipated solution are determined using the Galerkin method for minimizing errors. Before the minimization process is to take place, the NPDE is converted into an operational matrix equation which, when inverted, yields values of the undefined coefficients in the expected solution. The nonlinear terms of the NPDE are combined in the …


Binary Neutron Star Mergers: Gravitational-Wave Measurements Of Their Parameters And The Nuclear Equation Of State, Daniel Roger Finstad 2021 Syracuse University

Binary Neutron Star Mergers: Gravitational-Wave Measurements Of Their Parameters And The Nuclear Equation Of State, Daniel Roger Finstad

Dissertations - ALL

Since making the first direct detection of gravitational waves in 2015, the Advanced Laser Interferometer Gravitational-Wave Observatory (LIGO) together with the Virgo observatory has detected an additional 51 confirmed signals from binary mergers. Two of these signals, GW170817 and GW190425, were identified as binary neutron star mergers. As detector sensitivity improves we expect to see many more binary neutron star merger events, both from future observing runs of the LIGO-Virgo network and from planned third-generation detectors. These new detections will provide an exquisite look at the nature of these systems and of neutron stars themselves. This thesis describes how gravitational-wave …


Elucidating The Effects Of Oxygen- And Nitrogen-Containing Functional Groups In Graphene Nanomaterials For Applied Electrochemistry By Density Functional Theory, Sanju Gupta, Nicholas Dimakis 2021 The University of Texas Rio Grande Valley

Elucidating The Effects Of Oxygen- And Nitrogen-Containing Functional Groups In Graphene Nanomaterials For Applied Electrochemistry By Density Functional Theory, Sanju Gupta, Nicholas Dimakis

Physics & Astronomy Faculty Publications

Graphene nanomaterials functionalized with oxygen groups [graphene oxide (GO) and reduced GO (rGO)] are either doped with element nitrogen or nitrogen-containing aromatic moieties followed by the investigation of electrochemical properties that generally show enhanced electroanalytical performance. We studied structural, morphological, and physical–chemical properties using correlative techniques. While we attribute their improved properties promoted simultaneously by topologically interconnected mesoporous network morphology, the presence of heteroatom species, and lattice vibrational structure, the complex interpretation requires the need to supplement the experimental observations with theoretical calculations for further insights. The complex interplay of pore size and redox properties revealing distinctive supercapacitive (ion-adsorption controlled) …


Table Of Contents, 2021 University of South Carolina

Table Of Contents

Journal of the South Carolina Academy of Science

No abstract provided.


2021 Scas Annual Meeting Program And Bulletin, 2021 University of South Carolina

2021 Scas Annual Meeting Program And Bulletin

Journal of the South Carolina Academy of Science

No abstract provided.


Terrestrial Planet Formation In A Circumbinary Disc Around A Coplanar Binary, Anna C. Childs, Rebecca G. Martin 2021 University of Nevada, Las Vegas

Terrestrial Planet Formation In A Circumbinary Disc Around A Coplanar Binary, Anna C. Childs, Rebecca G. Martin

Physics & Astronomy Faculty Research

With N-body simulations, we model terrestrial circumbinary planet (CBP) formation with an initial surface density profile motivated by hydrodynamic circumbinary gas disc simulations. The binary plays an important role in shaping the initial distribution of bodies. After the gas disc has dissipated, the torque from the binary speeds up the planet formation process by promoting body-body interactions but also drives the ejection of planet building material from the system at an early time. Fewer but more massive planets form around a close binary compared to a single star system. A sufficiently wide or eccentric binary can prohibit terrestrial planet formation. …


The Large Area Burst Polarimeter (Leap) A Nasa Mission Of Opportunity For The Iss, Bing Zhang, Numerous Authors, See Full List Below 2021 University of Nevda, Las Vegas

The Large Area Burst Polarimeter (Leap) A Nasa Mission Of Opportunity For The Iss, Bing Zhang, Numerous Authors, See Full List Below

Physics & Astronomy Faculty Research

The LargE Area Burst Polarimeter (LEAP) will radically improve our understanding of some of the most energetic phenomena in our Universe by exposing the underlying physics that governs astrophysical jets and the extreme environment surrounding newborn compact objects. LEAP will do this by making the highest fidelity polarization measurements to date of the prompt gamma-ray emission from a large sample of Gamma-Ray Bursts (GRBs). The science objectives are met with a single instrument deployed as an external payload on the ISS-a wide FOV Compton polarimeter that measures GRB polarization from 50-500 keV and GRB spectra from ∼10 keV to 5 …


Catalog Of Edge-On Galaxies Using The Pan-Starrs1 Survey Data, Dimitry I. Makarov, S. Savchenko, Alexander V. Mosenkov, Dmitry V. Bizyaev, Vladimir P. Reshetnikov, Alexandra V. Antipova, I. Tikhonenko, P. Usachev, S. Borisov, L. Makarova, Stefan Kautsch, A. Marchuk, E. Rub Edukov, M. Skryabina, P. Smirnova 2021 Russian Academy of Sciences

Catalog Of Edge-On Galaxies Using The Pan-Starrs1 Survey Data, Dimitry I. Makarov, S. Savchenko, Alexander V. Mosenkov, Dmitry V. Bizyaev, Vladimir P. Reshetnikov, Alexandra V. Antipova, I. Tikhonenko, P. Usachev, S. Borisov, L. Makarova, Stefan Kautsch, A. Marchuk, E. Rub Edukov, M. Skryabina, P. Smirnova

Chemistry and Physics Faculty Articles

We have created a catalog of edge-on galaxies based on the publicly available DR2 data from the Pan-STARRS survey. The intensive use of an artificial neural network has significantly improved the quality of candidate selection. The catalog provides homogeneous information on astrometry, photometry, and non-parametric morphological statistics for 16551 edge-on galaxies. Our catalog is intended for studying the three-dimensional structure of galaxies with different morphologies and the scaling relations for disks and bulges.


Development And Distribution Of Thermometry Hardware For The Simons Observatory, Samuel Day-Weiss 2021 Yale University

Development And Distribution Of Thermometry Hardware For The Simons Observatory, Samuel Day-Weiss

The Yale Undergraduate Research Journal

The Simons Observatory (SO) is a new cosmic microwave background (CMB) experiment consisting of four telescopes. SO is being constructed at an elevation of 5,190 meters on Cerro Toco in the Atacama Desert in Chile, and is set to begin observation in 2022. SO will employ 60,000 detectors, yielding a sensitivity greater than all previous CMB experiments. To achieve low noise performance the telescope cryostats will be cooled to ~100 mK using low temperature dilution refrigerators. Measuring cryostat temperatures is essential for pre-deployment testing, telescope installation, and telescope monitoring during observation. The purpose of this project is to design, build, …


On The Rectilinear Motion Of Three Bodies Mutually Attracting Each Other, Sylvio R. Bistafa 2021 University of Sao Paulo

On The Rectilinear Motion Of Three Bodies Mutually Attracting Each Other, Sylvio R. Bistafa

Euleriana

This is an annotated translation from Latin of E327 -- De motu rectilineo trium corporum se mutuo attrahentium (“On the rectilinear motion of three bodies mutually attracting each other”). In this publication, Euler considers three bodies lying on a straight line, which are attracted to each other by central forces inversely proportional to the square of their separation distance (inverse-square law). Here Euler finds that the parameter that controls the relative distances among the bodies is given by a quintic function.


Euler's Three-Body Problem, Sylvio R. Bistafa 2021 University of Sao Paulo

Euler's Three-Body Problem, Sylvio R. Bistafa

Euleriana

In physics and astronomy, Euler's three-body problem is to solve for the motion of a body that is acted upon by the gravitational field of two other bodies. This problem is named after Leonhard Euler (1707-1783), who discussed it in memoirs published in the 1760s. In these publications, Euler found that the parameter that controls the relative distances among three collinear bodies is given by a quintic equation. Later on, in 1772, Lagrange dealt with the same problem, and demonstrated that for any three masses with circular orbits, there are two special constant-pattern solutions, one where the three bodies remain …


Mass-Velocity Dispersion Relation In Manga Brightest Cluster Galaxies, Stacy S. McGaugh 2021 Case Western Reserve University

Mass-Velocity Dispersion Relation In Manga Brightest Cluster Galaxies, Stacy S. Mcgaugh

Faculty Scholarship

We investigate a kinematic scaling relation between the baryonic mass and the flat velocity dispersion, i.e., mass- velocity dispersion relation (MVDR), from the brightest cluster galaxies (BCGs) to the galaxy clusters. In our studies, the baryonic mass of BCGs is mainly estimated by photometry. The velocity dispersion profiles are explored with the integrated field unit by Mapping Nearby Galaxies at Apache Point Observatory (MaNGA). For the first time, we reveal two significant results with 54 MaNGA BCGs: (1) the flat velocity dispersion profiles; (2) a tight empirical relation on the BCG-cluster scale together with cluster samples, i.e., MVDR, = - …


The Hubble Pancet Program: Transit And Eclipse Spectroscopy Of The Strongly Irradiated Giant Exoplanet Wasp-76b, Guangwei Fu, Drake Deming, Joshua Lothringer, Nikolay Nikolov, David K. Sing, Eliza M.-R. Kempton, Jegug Ih, Thomas M. Evans, Kevin Stevenson, Hannah R. Wakeford, Joseph E. Rodriguez, Jason D. Eastman, Keivan Stassun, Gregory W. Henry, Mercedes López-Morales, Monika Lendl, Dennis M. Conti, Chris Stockdale, Karen Collins, John Kielkopf, Joanna K. Barstow, Jorge Sanz-Forcada, David Ehrenreich, Vincent Bourrier, Leonardo A. dos Santos 2021 University of Maryland at College Park

The Hubble Pancet Program: Transit And Eclipse Spectroscopy Of The Strongly Irradiated Giant Exoplanet Wasp-76b, Guangwei Fu, Drake Deming, Joshua Lothringer, Nikolay Nikolov, David K. Sing, Eliza M.-R. Kempton, Jegug Ih, Thomas M. Evans, Kevin Stevenson, Hannah R. Wakeford, Joseph E. Rodriguez, Jason D. Eastman, Keivan Stassun, Gregory W. Henry, Mercedes López-Morales, Monika Lendl, Dennis M. Conti, Chris Stockdale, Karen Collins, John Kielkopf, Joanna K. Barstow, Jorge Sanz-Forcada, David Ehrenreich, Vincent Bourrier, Leonardo A. Dos Santos

Information Systems and Engineering Management Research Publications

Ultra-hot Jupiters with equilibrium temperatures greater than 2000 K are uniquely interesting targets as they provide us crucial insights into how atmospheres behave under extreme conditions. This class of giant planets receives intense radiation from their host star and usually has strongly irradiated and highly inflated atmospheres. At such a high temperature, cloud formation is expected to be suppressed and thermal dissociation of water vapor could occur. We observed the ultra-hot Jupiter WASP-76b with seven transits and five eclipses using the Hubble Space Telescope and the Spitzer Space Telescope (Spitzer) for a comprehensive study of its atmospheric chemical and physical …


Space Science And Social Media: Automating Science Communication On Twitter, Maia Williams 2021 Bowling Green State University

Space Science And Social Media: Automating Science Communication On Twitter, Maia Williams

Honors Projects

This project analyzes how social media is used to engage general audiences in astronomy and space science, as well as ways to improve engagement through automation. Tweets from five space science organizations were sampled. The engagement rate for each tweet was calculated from the number of interactions it received. Accounts that tweet more per day had more followers, and accounts with more followers received more interactions. This project also investigated how to build a Twitter bot to automate science communication. Using NASA Application Programming Interfaces, a Twitter bot was written in Python to tweet images taken by the NASA Mars …


Dirac-Born-Infeld Warm Inflation Realization In The Strong Dissipation Regime, Meysam Motaharfar, Rudnei O. Ramos 2021 Louisiana State Univ, Dept Phys & Astron, Baton Rouge, LA 70803 USA

Dirac-Born-Infeld Warm Inflation Realization In The Strong Dissipation Regime, Meysam Motaharfar, Rudnei O. Ramos

Faculty Publications

We consider warm inflation with a Dirac-Born-Infeld (DBI) kinetic term in which both the non-equilibrium dissipative particle production and the sound speed parameter slow the motion of the inflaton field. We find that a low sound speed parameter removes, or at least strongly suppresses, the growing function appearing in the scalar of curvature power spectrum of warm inflation, which appears due to the temperature dependence in the dissipation coefficient. As a consequence of that, a low sound speed helps to push warm inflation into the strong dissipation regime, which is an attractive regime from a model building and phenomenological perspective. …


Extended Search For Supernovalike Neutrinos In Nova Coincident With Ligo/Virgo Detections, M. A. Acero, P. Adamson, L. Aliaga, N. Anfimov, A. Antoshkin, E. Arrieta-Diaz, L. Asquith, A. Aurisano, A. Back, C. Backhouse, M. Baird, N. Balashov, P. Baldi, B. A. Bambah, S. Bashar, K. Bays, R. Bernstein, V. Bhatnagar, B. Bhuyan, J. Bian, Roberto Petti, Et. Al. 2021 University of South Carolina

Extended Search For Supernovalike Neutrinos In Nova Coincident With Ligo/Virgo Detections, M. A. Acero, P. Adamson, L. Aliaga, N. Anfimov, A. Antoshkin, E. Arrieta-Diaz, L. Asquith, A. Aurisano, A. Back, C. Backhouse, M. Baird, N. Balashov, P. Baldi, B. A. Bambah, S. Bashar, K. Bays, R. Bernstein, V. Bhatnagar, B. Bhuyan, J. Bian, Roberto Petti, Et. Al.

Faculty Publications

A search is performed for supernovalike neutrino interactions coincident with 76 gravitational wave events detected by the LIGO/Virgo Collaboration. For 40 of these events, full readout of the time around the gravitational wave is available from the NOvA Far Detector. For these events, we set limits on the fluence of the sum of all neutrino flavors of F < 7(4) × 1010 cm−2 at 90% C.L. assuming energy and time distributions corresponding to the Garching supernova models with masses 9.6ð27Þ M⊙. Under the hypothesis that any given gravitational wave event was caused by a supernova, this corresponds to a distance …


Dark Matter Detection Materials, James E. Harrison IV 2021 University of North Florida

Dark Matter Detection Materials, James E. Harrison Iv

PANDION: The Osprey Journal of Research and Ideas

The purpose of this paper is to review the different methods and materials used in the detection of dark matter. Special attention is given to materials in the solid state, but other materials are briefly mentioned for the sake of completeness. After a review, we discuss the viability of each material as a detector, and determine what advantages each material has, and what method of detection works best for each material. We conclude by discussing the potential outcomes of a null detection.


Temporal And Spatial Variations In Three-Dimensional Seismic Oceanography, Zheguang Zou, Parsa Bakhtiari Rad, Leonardo MacElloni, Likun Zhang 2021 University of Mississippi

Temporal And Spatial Variations In Three-Dimensional Seismic Oceanography, Zheguang Zou, Parsa Bakhtiari Rad, Leonardo Macelloni, Likun Zhang

Faculty and Student Publications

Seismic oceanography is a new cross-discipline between geophysics and oceanography that uses seismic reflection data to image and study the oceanic water column. Previous work on seismic oceanography was largely limited to two-dimensional (2D) seismic data and methods. Here we explore and quantify temporal and spatial variations in three-dimensional (3D) seismic oceanography to address whether 3D seismic imaging is meaningful in all directions and how one can take advantage of the variations. From a 3D multichannel seismic survey acquired for oil and gas exploration in the Gulf of Mexico over a 6-month period, a 3D oceanic seismic volume was derived. …


Using Methanol Masers To Probe High Mass Star Forming Regions, Naomi S. Shechter, Anuj P. Sarma 2021 DePaul University, Chicago

Using Methanol Masers To Probe High Mass Star Forming Regions, Naomi S. Shechter, Anuj P. Sarma

DePaul Discoveries

Compared to low mass stars, the formation of high mass stars is not well understood. To understand better how high mass stars form, we can utilize masers, naturally amplified point sources of microwave radiation. One example is the methanol maser, which falls into two categories. Class I methanol masers form in the bipolar outflows from the protostar, and Class II masers form in the accretion disk. Their compact size and intensity make them an excellent source of information about the process of high mass star formation. We compiled a modest database of Class I and II methanol masers through a …


An Investigation Of Water Masers In High Mass Star Forming Regions, Eleanor A. Webb 2021 DePaul University

An Investigation Of Water Masers In High Mass Star Forming Regions, Eleanor A. Webb

DePaul Discoveries

Within deep space are massive molecular clouds and within these molecular clouds, stars form. In these regions of star formation, masers can occur. I studied the presence of water masers within these high mass star forming regions. This was done in order to ascertain whether or not there is a correlation between the intensity of water masers versus the star formation activity within the molecular clouds. My findings provide answers to my specific research questions and includes information on the location of the water masers I observed with the star-forming regions. These findings provide information on water masers and sets …


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