Open Access. Powered by Scholars. Published by Universities.®

Astrophysics and Astronomy Commons

Open Access. Powered by Scholars. Published by Universities.®

Other

Discipline
Institution
Keyword
Publication Year
Publication
Publication Type

Articles 1 - 30 of 60

Full-Text Articles in Astrophysics and Astronomy

Clea Labs For Stellar And Cosmological Astronomy Bottled For Silicon Macintosh, Hansika Reddy Bandela, Yuktha Shetty, Jack C. Straton Jan 2025

Clea Labs For Stellar And Cosmological Astronomy Bottled For Silicon Macintosh, Hansika Reddy Bandela, Yuktha Shetty, Jack C. Straton

Physics Faculty Publications and Presentations

Project CLEA -- CONTEMPORARY LABORATORY EXPERIENCES IN ASTRONOMY -- develops laboratory exercises that illustrate modern astronomical techniques using digital data and color images.

These Labs were developed for Windows, but the authors have bottled them for Silicon Macintosh computers.


Clea Labs For Planetary, Stellar, And Cosmological Astronomy Configured For 64-Bit Windows 11+ Machines, Itan Altamirano, Jack C. Straton Jan 2025

Clea Labs For Planetary, Stellar, And Cosmological Astronomy Configured For 64-Bit Windows 11+ Machines, Itan Altamirano, Jack C. Straton

Physics Faculty Publications and Presentations

Project CLEA -- CONTEMPORARY LABORATORY EXPERIENCES IN ASTRONOMY -- develops laboratory exercises that illustrate modern astronomical techniques using digital data and color images.

These Labs were developed for 32-bit Windows machines but PSU student Itan Altamirano reconfigured installation programs to bypass steps that ask for DVDs and allowing these 32-bit programs to work on 64-bit Windows 11+ computers.


Dual View Of The Z2-Gauged Xy Model In 3d, Piers Coleman, Anatoly Kuklov, Alexei Tsvelik Jan 2025

Dual View Of The Z2-Gauged Xy Model In 3d, Piers Coleman, Anatoly Kuklov, Alexei Tsvelik

Publications and Research

The Z2 gauged XY model is of long-standing interest both in the context of nematic order, and the study of fractionalization and superconductivity. This paper presents heuristic arguments that no deconfinement of the XY field occurs in this model and presents results of a large-scale Monte Carlo simulations on a cubic lattice which are consistent with this conclusion. The correlation radius determining the confinement is found to be growing rapidly as a function of the parameters in the phase featuring the nematic order. Thus, mesoscopic properties of the system can mimic deconfinement with high accuracy in some part of …


Clea Labs For Planetary Astronomy Bottled For Silicon Macintosh, Yuktha Shetty, Hansika Reddy Bandela, Jack C. Straton Jan 2025

Clea Labs For Planetary Astronomy Bottled For Silicon Macintosh, Yuktha Shetty, Hansika Reddy Bandela, Jack C. Straton

Physics Faculty Publications and Presentations

Project CLEA -- CONTEMPORARY LABORATORY EXPERIENCES IN ASTRONOMY -- develops laboratory exercises that illustrate modern astronomical techniques using digital data and color images.

These Labs were developed for Windows, but the authors have bottled them for Silicon Macintosh computers.


Propionamide (C2h5conh2): The Largest Peptide-Like Molecule In Space (Vol 919, 4, 2021), Juan Li, Junzhi Wang, Xing Lu, Vadim Ilyushin, Roman A. Motiyenko, Qian Gou, Eugene A. Alekseev, Donghui Quan Dr., Laurent Margules, Feng Gao, Frank J. Lovas, Yajun Wu, Edwin Bergin, Shanghuo Li, Zhiqiang Shen, Fujun Du, Meng Li, Siqi Zheng, Xingwu Zheng Jun 2022

Propionamide (C2h5conh2): The Largest Peptide-Like Molecule In Space (Vol 919, 4, 2021), Juan Li, Junzhi Wang, Xing Lu, Vadim Ilyushin, Roman A. Motiyenko, Qian Gou, Eugene A. Alekseev, Donghui Quan Dr., Laurent Margules, Feng Gao, Frank J. Lovas, Yajun Wu, Edwin Bergin, Shanghuo Li, Zhiqiang Shen, Fujun Du, Meng Li, Siqi Zheng, Xingwu Zheng

EKU Faculty and Staff Scholarship

No abstract provided.


Beam-Spin Asymmetry Σ For Σ- Hyperon Photoproduction Off The Neutron, N. Zachariou, E. Munevar, B. L. Berman, P. Bydžovský, A. Cieplý, G. Feldman, Y. Ilieva, P. Nadel-Turonski, D. Skoupil, A. V. Sarantsev, D. P. Watts, M. J. Amaryan, G. Angelini, W. R. Armstrong, H. Atac, H. Avakian, L. Barion, M. Bashkanov, M. Battaglieri, Steffen Strauch, Et. Al. Apr 2022

Beam-Spin Asymmetry Σ For Σ- Hyperon Photoproduction Off The Neutron, N. Zachariou, E. Munevar, B. L. Berman, P. Bydžovský, A. Cieplý, G. Feldman, Y. Ilieva, P. Nadel-Turonski, D. Skoupil, A. V. Sarantsev, D. P. Watts, M. J. Amaryan, G. Angelini, W. R. Armstrong, H. Atac, H. Avakian, L. Barion, M. Bashkanov, M. Battaglieri, Steffen Strauch, Et. Al.

Faculty Publications

We report a new measurement of the beam-spin asymmetry, Σ, for the γn → K + Σ− reaction using quasi-free neutrons in a liquid-deuterium target. The new dataset includes data at previously unmeasured photon energy and angular ranges, thereby providing new constraints on partial wave analyses used to extract properties of the excited nucleon states. The experimental data were obtained using the CEBAF Large Acceptance Spectrometer (CLAS), housed in Hall B of the Thomas Jefferson National Accelerator Facility (JLab). The CLAS detector measured reaction products from a liquid-deuterium target produced by an energy-tagged, linearly polarised photon beam with energies in …


Dayside Auroral Activity, Aine Merritt, Gerard J. Fasel Mar 2022

Dayside Auroral Activity, Aine Merritt, Gerard J. Fasel

Seaver College Research And Scholarly Achievement Symposium

The dayside aurora is greatly influenced by the solar wind. Many different types of dayside auroral features have been identified, including poleward-moving auroral forms (PMAFs), throat aurora, shock aurora, and diffuse aurora. This study looks at the dayside auroral activity using the BACC ground-based all-sky-cameras located in both Longyearbyen (Kjell Henriksen Observatory) and Ny-Alesund, Svalbard. There are times when PMAFs peel off the dayside auroral oval in an ordered fashion, elongated east-west arcs moving poleward. At other times, the dayside aurora displays arcs that have extreme brightening moving through the arcs as they exhibit swirls and become a bit chaotic …


Measurement Of Structure Dependent Radiative K+ -> E,Sup>(+) Vy Gamma Decays Using Stopped Positive Kaons, H. Ito, A. Kobayashi, S. Bianchin, T. Cao, C. Djalali, D. H. Dongwi, T. Gautam, D. Gill, M. D. Hasinoff, K. Horie, Y. Igarashi, J. Imazato, N. Kalantarians, H. Kawai, S. Kimura, S. Kodama, M. Kohl, H. Lu, O. Mineev, Steffen Strauch, Et. Al. Mar 2022

Measurement Of Structure Dependent Radiative K+ -> E,Sup>(+) Vy Gamma Decays Using Stopped Positive Kaons, H. Ito, A. Kobayashi, S. Bianchin, T. Cao, C. Djalali, D. H. Dongwi, T. Gautam, D. Gill, M. D. Hasinoff, K. Horie, Y. Igarashi, J. Imazato, N. Kalantarians, H. Kawai, S. Kimura, S. Kodama, M. Kohl, H. Lu, O. Mineev, Steffen Strauch, Et. Al.

Faculty Publications

The structure dependent radiative K + → e+νγ (KSD+e2γ) decay was investigated with stopped positive kaons. The e+ momentum spectra containing 574±30 KSD+e2γ events with a K + → μ+ν (Kμ2) background of 28 ± 19 events were measured with and without a photon in coincidence and analyzed with Monte Carlo simulations for acceptance and detector response to extract the ratio of the branching ratio of the KSD+e2γ decay and the K + → e+ν decay including the internal bremsstrahlung process (Ke2(γ )). …


Measurements Of The Electron-Helicity Asymmetry In The Quasi-Elastic A ((E) Over Right Arrow, E' O) Process, T. Kolar, S. J. Paul, P. Achenbach, H. Arenhoevel, A. Ashkenazi, J. Beričič, R. Böhm, D. Bosnar, T. Brecelj, E. Cline, E. O. Cohen, M. O. Distler, A. Esser, I. Friščić, R. Gilman, C. Giusti, M. Heilig, M. Hoek, D, Izraeli, Steffen Strauch, Et. Al. Jan 2022

Measurements Of The Electron-Helicity Asymmetry In The Quasi-Elastic A ((E) Over Right Arrow, E' O) Process, T. Kolar, S. J. Paul, P. Achenbach, H. Arenhoevel, A. Ashkenazi, J. Beričič, R. Böhm, D. Bosnar, T. Brecelj, E. Cline, E. O. Cohen, M. O. Distler, A. Esser, I. Friščić, R. Gilman, C. Giusti, M. Heilig, M. Hoek, D, Izraeli, Steffen Strauch, Et. Al.

Faculty Publications

We present measurements of the electron helicity asymmetry in quasi-elastic proton knockout from 2H and 12C nuclei by polarized electrons. This asymmetry depends on the fifth structure function, is antisymmetric with respect to the scattering plane, and vanishes in the absence of final-state interactions, and thus it provides a sensitive tool for their study. Our kinematics cover the full range in off-coplanarity angle θpq, with a polar angle θpq coverage up to about 8. The missing energy resolution enabled us to determine the asymmetries for knock-out resulting in different states of the residual …


The Differentialgeometry Package, Ian M. Anderson, Charles G. Torre Jan 2022

The Differentialgeometry Package, Ian M. Anderson, Charles G. Torre

Downloads

This is the entire DifferentialGeometry package, a zip file (DifferentialGeometry.zip) containing (1) a Maple Library file, DifferentialGeometryUSU.mla, (2) a Maple help file DifferentialGeometry.help, (3) a Maple Library file, DGApplicatons.mla. This is the latest version of the DifferentialGeometry software; it supersedes what is released with Maple.

Installation instructions


A New Non-Inheriting Homogeneous Solution Of The Einstein-Maxwell Equations With Cosmological Term, Charles G. Torre Jan 2022

A New Non-Inheriting Homogeneous Solution Of The Einstein-Maxwell Equations With Cosmological Term, Charles G. Torre

Research Vignettes

No abstract provided.


What's New In Differentialgeometry Release Dg2022, Ian M. Anderson, Charles G. Torre Jan 2022

What's New In Differentialgeometry Release Dg2022, Ian M. Anderson, Charles G. Torre

Tutorials on... in 1 hour or less

This Maple worksheet demonstrates the salient new features and functionalities of the 2022 release of the DifferentialGeometry software package.


Double Polarisation Observable G For Single Pion Photoproduction From The Proton, N. Zachariou, D. P. Watts, J. Mcandrew, L. Zana, M. Bashkanov, I. I. Strakovsky, R. Workman, A. V. Sarantsev, V. Nikonov, K. P. Adhikari, S. Adhikari, M. J. Amaryan, G. Angelini, W. R. Armstrong, H. Atac, N. A. Baltzell, L. Barion, M. Battaglieri, I. Bedlinskiy, F. Benmokhtar, Steffen Strauch, Et. Al. Jun 2021

Double Polarisation Observable G For Single Pion Photoproduction From The Proton, N. Zachariou, D. P. Watts, J. Mcandrew, L. Zana, M. Bashkanov, I. I. Strakovsky, R. Workman, A. V. Sarantsev, V. Nikonov, K. P. Adhikari, S. Adhikari, M. J. Amaryan, G. Angelini, W. R. Armstrong, H. Atac, N. A. Baltzell, L. Barion, M. Battaglieri, I. Bedlinskiy, F. Benmokhtar, Steffen Strauch, Et. Al.

Faculty Publications

We report measurements of π+ and π0 meson photoproduction from longitudinally spin-polarised protons by an energy tagged (0.73-2.3 GeV) and linearly polarised photon beam. A close to complete solid angle coverage for the reaction products was provided by the CEBAF Large Acceptance Spectrometer at Jefferson Laboratory. The double-polarisation observable G is extracted from Maximum Likelihood fits to the data, enabling the first accurate determination for the reaction γ p → π+n, while also significantly extending the kinematic coverage for γ p → π0 p. This large data set provides an important constraint on the properties …


Standard Non-Uniform Noise Dataset, Andres Imperial, John M. Edwards May 2021

Standard Non-Uniform Noise Dataset, Andres Imperial, John M. Edwards

Browse all Datasets

Fixed Pattern Noise Non-Uniformity Correction through K-Means Clustering

Fixed pattern noise removal from imagery by software correction is a practical approach compared to a physical hardware correction because it allows for correction post-capture of the imagery. Fixed pattern noise presents a unique challenge for de-noising techniques as the noise does not present itself where large number statistics are effective. Traditional noise removal techniques such as blurring or despeckling produce poor correction results because of a lack of noise identification. Other correction methods developed for fixed pattern noise can often present another problem of misidentification of noise. This problem can result …


In-Class Activities For Openstax Astronomy, Rosa Williams, Kimberly Shaw Apr 2020

In-Class Activities For Openstax Astronomy, Rosa Williams, Kimberly Shaw

Physics and Astronomy Ancillary Materials

This set of in-class activities in Microsoft Word format are intended to supplement OpenStax Astronomy. Topics include:

  • Atmospheric Gas
  • Celestial Sphere
  • Dwarf Planets
  • Earth Size
  • Earth Impact
  • Greenhouse Gases and Climate Change
  • Jovian Planet
  • Jovian Moon and Ring
  • Mars Atmosphere and Climate
  • Solar System Formation and Scale
  • Sunspots
  • Terrestrial Planet and Lunar Features
  • Venus Atmosphere and Climate


Meps Data Assimilation System, Robert W. Schunk, Larry Gardner Nov 2019

Meps Data Assimilation System, Robert W. Schunk, Larry Gardner

Browse all Datasets

For the current funding opportunity we propose to develop a master system that will enhance the user interface to the MEPS model and enable the scientific community to efficiently use the model. Furthermore, we will build and automate validation tools and improve the efficiency and robustness of the MEPS ensemble averaging scheme. Finally, we will explore the nest step toward a major advancement in MEPS b significantly improving the spatial resolution of one of the data assimilation models to explore meso- and small-scale features.


Descriptive Astronomy I: The Solar System (Csu), Rosa Williams, Kimberly Shaw Oct 2019

Descriptive Astronomy I: The Solar System (Csu), Rosa Williams, Kimberly Shaw

Physics and Astronomy Grants Collections

This Grants Collection for Descriptive Astronomy I was created under a Round Thirteen ALG Textbook Transformation Grant.

Affordable Learning Georgia Grants Collections are intended to provide faculty with the frameworks to quickly implement or revise the same materials as a Textbook Transformation Grants team, along with the aims and lessons learned from project teams during the implementation process.

Each collection contains the following materials:

  • Linked Syllabus
  • Initial Proposal
  • Final Report


Spacetime Groups, Ian M. Anderson, Charles G. Torre Jan 2019

Spacetime Groups, Ian M. Anderson, Charles G. Torre

Publications

A spacetime group is a connected 4-dimensional Lie group G endowed with a left invariant Lorentz metric h and such that the connected component of the isometry group of h is G itself. The Newman-Penrose formalism is used to give an algebraic classification of spacetime groups, that is, we determine a complete list of inequivalent spacetime Lie algebras, which are pairs (g,η), with g being a 4-dimensional Lie algebra and η being a Lorentzian inner product on g. A full analysis of the equivalence problem for spacetime Lie algebras is given which leads to a completely algorithmic solution to the …


Data From: Polar Topside Ionosphere During Geomagnetic Storms: Comparison Of Isis-Ii With Tdim, Jan J. Sojka, Dan Rice, Michael David, Robert W. Schunk, Robert Benson, H. G. James Mar 2018

Data From: Polar Topside Ionosphere During Geomagnetic Storms: Comparison Of Isis-Ii With Tdim, Jan J. Sojka, Dan Rice, Michael David, Robert W. Schunk, Robert Benson, H. G. James

Browse all Datasets

Output files from runs of the TDIM ionospheric model used for calculations and electron density profiles from ISIS-II and TDIM used in figures in the article in Radio Science.


Examples Of The Birkhoff Theorem And Its Generalizations, Charles G. Torre Jan 2018

Examples Of The Birkhoff Theorem And Its Generalizations, Charles G. Torre

Tutorials on... in 1 hour or less

In this worksheet I demonstrate three versions of Birkhoff's theorem, which is a characterization of spherically symmetric solutions of the Einstein equations. The three versions considered here correspond to taking the "Einstein equations" to be: (1) the vacuum Einstein equations; (2) the Einstein equations with a cosmological constant (3) the Einstein-Maxwell equations. I will restrict my attention to 4-dimensional spacetimes.


How To Make Tetrads, Charles G. Torre Jan 2018

How To Make Tetrads, Charles G. Torre

How to... in 10 minutes or less

This is a worksheet which demonstrates tools for creating orthonormal and null tetrads for a given spacetime.


Symmetric Criticality In General Relativity, Charles G. Torre Jan 2018

Symmetric Criticality In General Relativity, Charles G. Torre

Research Vignettes

In this worksheet I explore the local Lagrangian version of the Principle of Symmetric Criticality (PSC) due to Anderson, Fels, and Torre], which asserts the commutativity of the processes (i) of symmetry reduction (for finding group-invariant fields) and (ii) forming Euler-Lagrange equations. There are two obstructions to PSC, which I will call the Lie algebra obstruction and the isotropy obstruction. In this worksheet I will illustrate these obstructions in the General Theory of Relativity.


Introduction To The Usu Library Of Solutions To The Einstein Field Equations, Ian M. Anderson, Charles G. Torre Dec 2017

Introduction To The Usu Library Of Solutions To The Einstein Field Equations, Ian M. Anderson, Charles G. Torre

Tutorials on... in 1 hour or less

This is a Maple worksheet providing an introduction to the USU Library of Solutions to the Einstein Field Equations. The library is part of the DifferentialGeometry software project and is a collection of symbolic data and metadata describing solutions to the Einstein equations.


Fermi-Lat Daily Monitoring Observations Of The Microquasar Cygnus X-1, Austin P. Waldron, Stephen R. Hood, Arash Bodaghee Apr 2017

Fermi-Lat Daily Monitoring Observations Of The Microquasar Cygnus X-1, Austin P. Waldron, Stephen R. Hood, Arash Bodaghee

Georgia College Student Research Events

Detection of gamma-ray emission from microquasars is important for understanding particle acceleration in the jet, and for constraining leptonic/hadronic emission models. We present a continuation of a 1-d likelihood analysis on gamma-ray observations by Fermi-LAT (0.1-10 GeV) of the accreting black hole candidate Cygnus X-1. Combining this gamma-ray data with available X-ray monitoring data from Swift and MAXI allowed us to reveal over a dozen days (in 2008-2016) during which Cyg X-1 displayed low-significance (3-4 sigma) excesses, many of which were contemporaneous with apparent transitions in the X-rays.


Perihelion Precession In The General Theory Of Relativity, Charles G. Torre Jan 2017

Perihelion Precession In The General Theory Of Relativity, Charles G. Torre

Tutorials on... in 1 hour or less

This is a relatively quick and informal sketch of a demonstration that general relativistic corrections to the bound Kepler orbits introduce a perihelion precession. Any decent textbook on the general theory of relativity will derive this result. My analysis aligns with that found in the good old text "Introduction to General Relativity", by Adler, Bazin and Schiffer.


The Kretschmann Scalar, Charles G. Torre Jan 2016

The Kretschmann Scalar, Charles G. Torre

How to... in 10 minutes or less

On a pseudo-Riemannian manifold with metric g, the "Kretschmann scalar" is a quadratic scalar invariant of the Riemann R tensor of g, defined by contracting all indices with g. In this worksheet we show how to calculate the Kretschmann scalar from a metric.


Data From: How Uncertainty In The Neutral Wind Limits The Accuracy Of Ionospheric Modeling And Forecasting, Michael David, Jan Sojka, Robert W. Schunk Jan 2016

Data From: How Uncertainty In The Neutral Wind Limits The Accuracy Of Ionospheric Modeling And Forecasting, Michael David, Jan Sojka, Robert W. Schunk

Browse all Datasets

Output files from runs of the TDIM ionospheric model used for the figures and calculations in the article in JGR Space Physics.


Differentialgeometry In Brno, Ian M. Anderson Dec 2015

Differentialgeometry In Brno, Ian M. Anderson

Presentations

This page will provide files supporting Ian Anderson's presentations in Brno, December 2015. The files can be found and downloaded from "Additional Files", below.

The files include:

(1) DifferentialGeometryUSU.mla: This is the Maple Library Archive file which provides all the DifferentialGeometry functionality. Here are Installation Instructions.

(2) DifferentialGeometry.help : this is the latest version of the DifferentialGeometry documentation. Copy this file to the same directory used for DifferentialGeometryUSU.mla (from step (1)).


Rainich-Type Conditions For Perfect Fluid Spacetimes, Dionisios Krongos, Charles G. Torre Dec 2014

Rainich-Type Conditions For Perfect Fluid Spacetimes, Dionisios Krongos, Charles G. Torre

Research Vignettes

In this worksheet we describe and illustrate a relatively simple set of new Rainich-type conditions on an n-dimensional spacetime which are necessary and sufficient for it to define a perfect fluid solution of the Einstein field equations. Procedures are provided which implement these Rainich-type conditions and which reconstruct the perfect fluid from the metric. These results provide an example of the idea of geometrization of matter fields in general relativity, which is a purely geometrical characterization of matter fields via the Einstein field equations.


1207-3900_Nir_Spex, Jonathan Gagné Apr 2014

1207-3900_Nir_Spex, Jonathan Gagné

Publications and Research

No abstract provided.