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Astrophysics and Astronomy

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2018

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Full-Text Articles in Physical Sciences and Mathematics

Table Of Contents Dec 2018

Table Of Contents

Journal of the South Carolina Academy of Science

No abstract provided.

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The Circular Restricted Four-Body Problem With Triaxial Primaries And Variable Infinitesimal Mass, Abdullah A. Ansari Dec 2018

The Circular Restricted Four-Body Problem With Triaxial Primaries And Variable Infinitesimal Mass, Abdullah A. Ansari

Applications and Applied Mathematics: An International Journal (AAM)

This paper investigates the circular restricted four-body problem in which three primaries are taken as triaxial rigid body which are placed at the vertices of an equilateral triangle and the fourth infinitesimal body is varying its mass with time. We used the Jeans law to determine equations of motion and then evaluated the Jacobi integral. In the next section, we have performed the computational work to draw the graphs of the equilibrium points in different planes, zero velocity curves, surfaces and the Newton-Raphson basins of attraction with the variations of the triaxiality parameters. Finally, we have examined the linear stability …

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Magic, Matrimony, And The Moon: Medieval Lunar Symbolism In J.R.R. Tolkien’S “The Lay Of Aotrou And Itroun” And “The Fall Of Arthur”, Kristine Larsen Nov 2018

Magic, Matrimony, And The Moon: Medieval Lunar Symbolism In J.R.R. Tolkien’S “The Lay Of Aotrou And Itroun” And “The Fall Of Arthur”, Kristine Larsen

Journal of Tolkien Research

This paper (originally delivered at the 2017 International Medieval Congress at the University of Leeds, UK) explores common lunar symbolism in "The Lay of Aotrou and Itroun" and "The Fall of Arthur."

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Thermal Evolution Modification Due To Radio-Wave Production Inside Rotating Magnetized Ns, Pulat Tadjimuratov Sep 2018

Thermal Evolution Modification Due To Radio-Wave Production Inside Rotating Magnetized Ns, Pulat Tadjimuratov

Bulletin of National University of Uzbekistan: Mathematics and Natural Sciences

We study effect of additional cooling mechanism on the thermal evolution of rotating magnetized neutron star (NS). The influence of general relativistic effects on charge distribution inside a NS leads to the qualitative distinction of space charge distribution inside the conducting crust from that inside the superconducting core which may play a source of a possible mechanism of radio-wave radiation production in the intermediate medium inside a rotating neutron star. This radiation may interact the matter of the neutron star and energy of the electromagnetic radiation can be transformed into the heating energy. The intensity of radio-wave radiation produced inside …

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Totality In Carbondale, Grant Haynes Aug 2018

Totality In Carbondale, Grant Haynes

The Hilltop Review

August 21 was one of the high points of 2017. That day a total solar eclipse tracked over much of the continental U.S. An early morning train ride brought me to Carbondale Illinois, the location of the eclipses longest duration. As totality neared clouds obscured this amazing celestial wonder, but they soon parted, and I was able to get a few spectacular photos of the eclipse, this one with the clouds that almost ruined it, is my favorite.

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The Proposed Origin Of Our Solar System With Planet Migration, Wayne R. Spencer Jul 2018

The Proposed Origin Of Our Solar System With Planet Migration, Wayne R. Spencer

Proceedings of the International Conference on Creationism

Two new models to explain the origin and history of our solar system are reviewed from a creation perspective, the Grand Tack model and the Nice model. These new theories propose that the four outer planets formed closer to the Sun, as well as closer together, than today. Then their orbits underwent periods of migration. Theories developed in the research on extrasolar planet systems are today being applied to our own solar system. The new migration models are finding much support from the planetary science community. These new models are summarized and evaluated Biblically and scientifically. Rather than demonstrating how …

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Consistent Young Earth Relativistic Cosmology, Phillip W. Dennis Jul 2018

Consistent Young Earth Relativistic Cosmology, Phillip W. Dennis

Proceedings of the International Conference on Creationism

We present a young earth creationist (YEC) model of creation that is consistent with distant light from distant objects in the cosmos. We discuss the reality of time from theological/philosophical foundations. This results in the rejection of the idealist viewpoint of relativity and the recognition of the reality of the flow of time and the existence of a single cosmological “now.” We begin the construction of the YEC cosmology with an examination of the “chronological enigmas” of the inhomogeneous solutions of the Einstein field equations (EFE) of General Relativity (GR). For this analysis we construct an inhomogeneous model by way …

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The Current State Of Creation Astronomy Ii, Danny R. Faulkner Jul 2018

The Current State Of Creation Astronomy Ii, Danny R. Faulkner

Proceedings of the International Conference on Creationism

It has been nearly twenty years since the previous review of the state of creation astronomy. Since then, much progress has occurred in developing a creation model of astronomy, and some of the recommendations of that earlier review have been carried out. Both the number of papers on astronomical topics published in the creation literature and their depth of coverage have increased tremendously. There has been less concern with criticism of evolutionary ideas as creationists have begun to develop their own models of astronomy. While emphasis on indicators of recent origin is not as great as it used to be, …

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Finite Element Analysis Of Large Body Deformation Induced By A Catastrophic Near Impact Event, Denver W. Seely, Andrew Bowman, Heechen Cho, Mark Horstemeyer Jul 2018

Finite Element Analysis Of Large Body Deformation Induced By A Catastrophic Near Impact Event, Denver W. Seely, Andrew Bowman, Heechen Cho, Mark Horstemeyer

Proceedings of the International Conference on Creationism

Finite element simulations of near impacts of terrestrial bodies are presented to investigate possible deformation behavior induced by a massive body during the creation week and/or Genesis Flood. Using the universal law of gravitation, a gravitationally loaded objected is subjected to the ‘pull’ of a near passing fly-by object, and the resulting surface deformations are studied. An Internal State Variable (ISV) pressure dependent plasticity model for silicate rocks (Cho et al., 2018) is used to model the deformation behavior and to capture the history effects involved during the complex surface loading/unloading found in a near impact event. The model is …

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Gamma-Ray Burst Classification: New Insights From Mining Pulse Data, Stanley Mcafee, Jon Hakkila Jul 2018

Gamma-Ray Burst Classification: New Insights From Mining Pulse Data, Stanley Mcafee, Jon Hakkila

Journal of the South Carolina Academy of Science

Despite being the most energetic electromagnetic explosions in the universe, gamma-ray bursts (GRBs) are still poorly understood. The literature recognizes two potentially different types of GRB progenitors, although statistical data suggest the existence of three GRB classes. Reliable inference of GRB physics depends on the identification of appropriate classification attributes, as well as on the statistical classification techniques used. It has recently been shown that pulses are the basic unit of GRB emission. We use new data describing GRB pulse characteristics, in conjunction with data mining tools, to provide a more reliable gamma-ray burst classification system and place additional constraints …

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Table Of Contents Jul 2018

Table Of Contents

Journal of the South Carolina Academy of Science

No abstract provided.

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A Wave From Einstein Jun 2018

A Wave From Einstein

DePaul Magazine

The discovery in 2015 of gravitational waves 100 years after Albert Einstein predicted their existence gave scientists a new way of understanding the universe. This discovery, made possible by decades of work and the collaborative efforts of astrophysicists around the world offers a window into how science advances. The concept of science as a way of knowing is discussed.

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Low Resolution Hi Imaging Of The Shield Galaxies, Masao L. Miazzo Jun 2018

Low Resolution Hi Imaging Of The Shield Galaxies, Masao L. Miazzo

Macalester Journal of Physics and Astronomy

We present low-resolution Karl G. Jansky Very Large Array D-configuration HI spectral line observations of 32 previously unobserved local-volume low-mass dwarf galaxies in the Survey of HI in Extremely Low-mass Dwarfs (SHIELD). SHIELD was designed to probe the physical characteristics of the objects that inhabit the faint end of the HI mass function as populated by the ALFALFA blind HI extragalactic survey. These low angular-resolution images localize the HI-gas and provide the first glimpse of the neutral interstellar medium in these sources. We quantify the total HI mass of each system, and, using SDSS imaging, we compare the HI and …

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Modeling Recombination In Solar Cells, Paul Chery Jun 2018

Modeling Recombination In Solar Cells, Paul Chery

Macalester Journal of Physics and Astronomy

Solar cells are a competitive alternative to nonrenewable energy sources such as fossil fuels. However, the efficiency of these devices is limited by photogenerated carrier recombination. We use a finite difference numerical model to study recombination phenomena in the absorber layer of solar cells including alternate recombination models and the effects of spatial distribution of recombination centers. We compare the effect of using the constant lifetime approximation for recombination to the full Shockley-Read-Hall expression in Silicon solar cells and find that the constant lifetime approximation holds for high defect densities but not for high photon flux densities. Finally, we simulate …

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How Many Quasars Have Extremely High Velocity Outflows?, Carla P. Quintero, Sean S. Haas, Paola Rodriguez Hidalgo Jun 2018

How Many Quasars Have Extremely High Velocity Outflows?, Carla P. Quintero, Sean S. Haas, Paola Rodriguez Hidalgo

IdeaFest: Interdisciplinary Journal of Creative Works and Research from Cal Poly Humboldt

No abstract provided.

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Searching For A Connection Between Radio Emission And Uv/Optical Absorption In Quasars, Sean S. Haas, Carla P. Quintero, Paola Rodriguez Hidalgo Jun 2018

Searching For A Connection Between Radio Emission And Uv/Optical Absorption In Quasars, Sean S. Haas, Carla P. Quintero, Paola Rodriguez Hidalgo

IdeaFest: Interdisciplinary Journal of Creative Works and Research from Cal Poly Humboldt

No abstract provided.

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Automation And Enhancements To The Erau Oscom System Space Situational Awareness, Sergei Bilardi, Patrick Rupp, Yevgeniy Lischuk, Joseph Stroup Jun 2018

Automation And Enhancements To The Erau Oscom System Space Situational Awareness, Sergei Bilardi, Patrick Rupp, Yevgeniy Lischuk, Joseph Stroup

Beyond: Undergraduate Research Journal

OSCOM, Optical tracking and Spectral characterization of CubeSats for Operational Missions, is a system developed at Embry-Riddle Aeronautical University to produce time-resolved photometry of small satellites using commercial-off-the-shelf hardware. OSCOM has been able to observe resident space objects (RSOs) as small as CubeSats using a Celestron 11” RASA and a CMOS machine vision camera from Allied Vision. By obtaining photometric measurements of satellites, a light curve can be constructed and used to help determine satellite characteristics such as spin rate, satellite state, and even satellite attitude. To enhance the OSCOM system’s ability to observe small satellites, there is ongoing development …

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Cataclysmic Variable Stars In The Sloan Digital Sky Survey, Sinead Humphrey, Samantha Smiley, Andres Munoz, Brian Saboriendo May 2018

Cataclysmic Variable Stars In The Sloan Digital Sky Survey, Sinead Humphrey, Samantha Smiley, Andres Munoz, Brian Saboriendo

DePaul Discoveries

The purpose of this study is to identify Cataclysmic Variables (CVs) using spectroscopic and photometric data. CVs are useful for studying plasma physics in extreme conditions such as the high temperature and strong magnetic fields seen in CV accretion disks. They are also critical for understanding the evolution of binary stars, both in the field and in globular clusters. This project used photometric and spectroscopic data from the Sloan Digital Sky Survey (SDSS) to identify and classify CVs. 6,000 objects were selected based on multi-color criteria and analyzed using spectral data. Approximately 1% of these objects in the sample were …

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Experimental Investigation Of A New Spiral Wingtip, Naseeb Ahmed Siddiqui, Mohamed Aldeeb, Waqar Asrar, Erwin Sulaeman Mar 2018

Experimental Investigation Of A New Spiral Wingtip, Naseeb Ahmed Siddiqui, Mohamed Aldeeb, Waqar Asrar, Erwin Sulaeman

International Journal of Aviation, Aeronautics, and Aerospace

Experiments on the relative merits and demerits of slotted wingtips mimicking a bird’s primary feathers have been performed. The real emargination length of feather tips, their flexibility and curved shapes during cruise are considered in the present study. The experiments were performed at a Reynolds number of 3.7 x 105 on a symmetric flat plate half wing of aspect ratio 3. Lift, drag and pitching moments were measured using a six component aerodynamic balance. Four different shapes inspired by bird primary feathers have been analysed. The rigid curved tip performed the best increasing the L/D ratio by 20%. This …

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Approximate Approaches For Nuclear Weak Interaction Rates In Astrophysics, Benjamin M. Anderson Jan 2018

Approximate Approaches For Nuclear Weak Interaction Rates In Astrophysics, Benjamin M. Anderson

Bridges: A Journal of Student Research

Nuclear weak interactions, like beta decay, are important inputs for modeling astrophysical explosions. In the allowed approximation, these processes proceed as Fermi or Gamow Teller (GT) processes where the spins of the electron and neutrino are anti-parallel or parallel, respectively. In the GT case, transition probability is spread over many final states in the daughter nucleus, with each probability determination requiring numerical integration of the available phase space. Developing a fast and accurate method for calculating each contribution to the total decay rate would provide reliable weak rate libraries for astrophysical modelers. The phase space integrand includes the classical statistical …

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