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Alignment Of The Western And Eastern Passage Tombs At Knowth Tomb 1, Frank Prendergast, Tom Ray 2015 Dublin Institute of Technology

Alignment Of The Western And Eastern Passage Tombs At Knowth Tomb 1, Frank Prendergast, Tom Ray

Book/Book Chapter

This report presents a summary account of two surveys undertaken by the authors to determine and interpret the alignments of the western and eastern passage tombs at Knowth, Co. Meath. The findings indicate that contrary to earlier suggestions, the eastern passage and the western passage (inner and outer) are not aligned towards sunrise and sunset respectively at the period of the vernal and autumnal equinoxes.


Video-Tutorials For Tech Sign Vocabulary In Astronomy, Judy Egelston-Dodd, Simon Ting 2014 Rochester Institute of Technology

Video-Tutorials For Tech Sign Vocabulary In Astronomy, Judy Egelston-Dodd, Simon Ting

Journal of Science Education for Students with Disabilities

This article describes the mediated American Sing Language (ASL) presentation of technical vocabulary and definitions within the context of a web-based astronomy course for first year students at the National Technical Institute for the Deaf at Rochester Institute of Technology (Rochester, NY). Deaf students showed achievement gains with fewer astronomy misconceptions. Also, student ratings of instructor ASL skill, as reported on the student rating system, were higher after students used the ASL vocabulary videos.


Characterizing The Quiescent X-Ray Variability Of The Black Hole Low-Mass X-Ray Binary V404 Cyg, F Bernardini, E. M. Cackett 2014 Wayne State University

Characterizing The Quiescent X-Ray Variability Of The Black Hole Low-Mass X-Ray Binary V404 Cyg, F Bernardini, E. M. Cackett

Physics and Astronomy Faculty Research Publications

We conducted the first long-term (75 d) X-ray monitoring of the black hole low-mass X-ray binary V404 Cyg, with the goal of understanding and characterizing its variability during quiescence. The X-ray light curve of V404 Cyg shows several flares on time-scales of hours with a count rate change of a factor of about 5–8. The root-mean-square variability isFvar = 57.0 ± 3.2 per cent. The first-order structure function is consistent with both a power spectrum of index −1 (flicker noise), or with a power spectrum of index 0 (white noise), implying that the light curve is variable ...


The Unified Astronomy Thesaurus: Bringing Together People, Terms, And Organizations To Classify Infinity... And Beyond!, Katie Frey 2014 University of Massachusetts Medical School

The Unified Astronomy Thesaurus: Bringing Together People, Terms, And Organizations To Classify Infinity... And Beyond!, Katie Frey

University of Massachusetts and New England Area Librarian e-Science Symposium

Objective

To create a Unified Astronomy Thesaurus as an open, interoperable, and community supported thesaurus. The UAT will bring together existing Astronomy and Astrophysics vocabularies into a single, freely-available, online thesaurus, available to publishers, authors, and everyone else with an interest in classifying astronomical content.

Methods

Because astronomy and astrophysics are fast-moving fields, terms that are common today, such as ‘exoplanets’ and ‘dark energy’, were relatively unknown 10 years ago. In order to keep up with the ever-changing field of astronomy, the UAT will solicit suggestions and recommendations from the astronomy community at large. A librarian will be in place ...


The Stardust Interstellar Dust Collector Crater Origins And Hypervelocity Cratering At Oblique Angles In Aluminum Foil, Harison Wiesman 2014 Washington University in St. Louis

The Stardust Interstellar Dust Collector Crater Origins And Hypervelocity Cratering At Oblique Angles In Aluminum Foil, Harison Wiesman

Undergraduate Theses—Unrestricted

From 1999 to 2006 the NASA Stardust mission collected cometary particles from the Wild 2 comet and interstellar dust from the interstellar medium in two collectors made from aerogel tiles and aluminum foil. By studying their isotopic compositions, these particles can provide us with information about nucleosynthetic processes in stars. Both collector trays are being studied for traces of these particles, though a number of challenges have arisen in doing so. Identifying impact craters in the aluminum foil on the interstellar collector tray has been incredibly difficult. In addition to being only a few micrometers or less in diameter, many ...


Survey Of ‘Low-Z’ Particles From The Interplanetary Dust Collection In Search Of Idps, Harison Wiesman 2014 Washington University in St. Louis

Survey Of ‘Low-Z’ Particles From The Interplanetary Dust Collection In Search Of Idps, Harison Wiesman

Undergraduate Theses—Unrestricted

Micrometeorites are one of the most common types of extraterrestrial material that fall to the Earth, beside meteorites and interplanetary dust particles (IDPs). All of these materials are known to contain presolar grains that, when studied in the laboratory, provide information about the origin of the solar system and help to constrain models of nucleosynthesis in stars. Recent studies of micrometeorites revealed the presence of a group of particles with very high C contents. These ultra-carbonaceous Antarctic micrometeorites (UCAMMs) are fine-grained, fluffy particles dominated by highly disordered carbonaceous matter. The presence of H and N isotopic anomalies, abundant presolar grains ...


Direct Numerical Simulations Of Magnetic Helicity Conserving Astrophysical Dynamos, Alex J. Cridland 2014 McMaster University

Direct Numerical Simulations Of Magnetic Helicity Conserving Astrophysical Dynamos, Alex J. Cridland

Open Access Dissertations and Theses

Here we present direct numerical simulations of a shearing box which models the MHD turbulence in astrophysical systems with cylindrical geometries. The purpose of these simulations is to detect the source of the electromotive force - the driver of large scale magnetic field evolution. This electromotive force is responsible for the large scale dynamo action which builds and maintains the magnetic field against dissipation in plasmas. We compare the estimates of the electromotive force from the kinematic approximation of mean field theory - the most prevalent theory for astrophysical dynamos - with a modified version of mean field theory which restricts the electromotive ...


Development Of A Thgem Imaging Detector With Delay Line Readout, Andrei Hanu 2014 McMaster University

Development Of A Thgem Imaging Detector With Delay Line Readout, Andrei Hanu

Open Access Dissertations and Theses

Position sensitive detectors represent a class of particle detectors widely used in high-energy physics, astrophysics, biophysics and medicine for imaging the spatial distribution of various radioactive sources. In recent years, a new class of gas based detectors, so-called micropattern gas detectors (MPGDs), has emerged. While modern MPGDs rival solid state detectors in terms of spatial and temporal resolution, their cost of production is significantly lower. A Thick Gaseous Electron Multiplier (THGEM) imaging detector, with a two-dimensional delay line readout, has been constructed as a concept for a large area imaging detector with reasonable spatial resolution. The delay line based THGEM ...


What You See Is What You Get: Synthetic Photometry Of Hydrodynamic Simulations Of Binary Star Systems, Kevin A. Sooley 2014 McMaster University

What You See Is What You Get: Synthetic Photometry Of Hydrodynamic Simulations Of Binary Star Systems, Kevin A. Sooley

Open Access Dissertations and Theses

In this thesis we present a procedure by which synthetic photometry of a hydrodynamic model of star or star-like object can be calculated in a regime where the photosphere is not radially resolved. In order to properly model the unresolved photosphere, we present a method where pressure and density are integrated outward from the outermost resolved radius of the star and then interpolated in temperature-surface gravity space between a set of MARCS \citep{Gustafsson2008a} stellar atmosphere models. These interpolations are accurate to within 10\% of expected temperature values and are determined by minimizing the difference between the integrated pressure, density ...


On Deflection Of Potentially Dangerous Asteroids, Josh Fixelle, Mikhail Kagan 2014 Indiana University – Purdue University Fort Wayne

On Deflection Of Potentially Dangerous Asteroids, Josh Fixelle, Mikhail Kagan

American Journal of Undergraduate Research

As has been widely discussed recently, our planet may become a target for asteroids. We consider several scenarios proposed to prevent asteroid collisions with Earth. The asteroid 99942 Apophis is considered as a typical representative. Among others, the recent “gravitational tractor” scenario [Lu & Love (2005)] is discussed. For a simplistic toy-model we obtain estimates for both the mass of the tractor and the amount of fuel required to tow a potentially dangerous asteroid off-course so as to avoid a collision with the Earth. In addition, we analyze two more scenarios titled “sling-shot” and “bumping”, and comment on their relative efficiency ...


Ogden College News, Cheryl Stevens, Dean 2014 Western Kentucky University

Ogden College News, Cheryl Stevens, Dean

Ogden College of Science & Engineering Publications

No abstract provided.


Multi-Wavelength Coverage Of State Transitions In The New Black Hole X-Ray Binary Swift J1910.2-0546, N. Degenaar, D. Maitra, E. M. Cackett, M. T. Reynolds, J M. Miller, R. C. Reis, A L. King, K. Gültekin, C D. Bailyn, M M. Buxton, R K. D MacDonald, A. C. Fabian, D B. Fox, E. S. Rykoff 2014 Wayne State University

Multi-Wavelength Coverage Of State Transitions In The New Black Hole X-Ray Binary Swift J1910.2-0546, N. Degenaar, D. Maitra, E. M. Cackett, M. T. Reynolds, J M. Miller, R. C. Reis, A L. King, K. Gültekin, C D. Bailyn, M M. Buxton, R K. D Macdonald, A. C. Fabian, D B. Fox, E. S. Rykoff

Physics and Astronomy Faculty Research Publications

Understanding howblack holes accrete and supply feedback to their environment is one of the outstanding challenges of modern astrophysics. Swift J1910.2–0546 is a candidate black hole low-mass X-ray binary that was discovered in 2012 when it entered an accretion outburst. To investigate the binary configuration and the accretion morphology, we monitored the evolution of the outburst for ≃3 months at X-ray, UV, optical (B,V,R,I), and near-infrared (J,H,K) wavelengths using Swift and SMARTS. The source evolved from a hard to a soft X-ray spectral state with a relatively cold accretion disk that peaked at ...


Session B-5: Planetary Science And The Ngss, Eric Hawker 2014 Illinois Mathematics and Science Academy

Session B-5: Planetary Science And The Ngss, Eric Hawker

Professional Learning Day

The goal of this session is to use what we understand about other planets and moons in our Solar System in order to get a better understanding of the Earth.


The Spacetime Geometry Of A Null Electromagnetic Field, Charles G. Torre 2014 Utah State University

The Spacetime Geometry Of A Null Electromagnetic Field, Charles G. Torre

Charles G. Torre

We give a set of local geometric conditions on a spacetime metric which are necessary and sufficient for it to be a null electrovacuum, that is, the metric is part of a solution to the Einstein-Maxwell equations with a null electromagnetic field. These conditions are restrictions on a null congruence canonically constructed from the spacetime metric, and can involve up to five derivatives of the metric. The null electrovacuum conditions are counterparts of the Rainich conditions, which geometrically characterize non-null electrovacua. Given a spacetime satisfying the conditions for a null electrovacuum, a straightforward procedure builds the null electromagnetic field from ...


The Spacetime Geometry Of A Null Electromagnetic Field, Charles G. Torre 2014 Utah State University

The Spacetime Geometry Of A Null Electromagnetic Field, Charles G. Torre

Presentations and Publications

We give a set of local geometric conditions on a spacetime metric which are necessary and sufficient for it to be a null electrovacuum, that is, the metric is part of a solution to the Einstein–Maxwell equations with a null electromagnetic field. These conditions are restrictions on a null congruence canonically constructed from the spacetime metric, and can involve up to five derivatives of the metric. The null electrovacuum conditions are counterparts of the Rainich conditions, which geometrically characterize non-null electrovacua. Given a spacetime satisfying the conditions for a null electrovacuum, a straightforward procedure builds the null electromagnetic field ...


Deposition And Analysis Of Copper Indium Disulfide For Photovoltaic Applications, Frederick Wade 2014 Macalester College

Deposition And Analysis Of Copper Indium Disulfide For Photovoltaic Applications, Frederick Wade

Macalester Journal of Physics and Astronomy

Thin Film semiconductors were created through the methods of electrochemistry to produce a copper, indium and sulfur metal alloy that could be placed on a stainless steel substrate. We observed other properties regarding the relative indium to copper relationships and both the macro and micro structure of the final product. X-­‐ray diffraction, SEM imaging, and atomic absorption spectroscopy data suggest a relatively intact metal alloy, but also an inaccurate ratio of indium to copper.


Photometric And Spectroscopic Analysis Of Young, Nearby Open Cluster Collinder 70, Clara M. Thomann 2014 Macalester College

Photometric And Spectroscopic Analysis Of Young, Nearby Open Cluster Collinder 70, Clara M. Thomann

Macalester Journal of Physics and Astronomy

We present the results of a wide-field (80’ x 80’) photometric and spectroscopic survey of the young open cluster Collinder 70, which is also known as the ORI OB 1b association, centered on the central star of Orion’s belt, ε Ori (Alnilam). Seventy Coll 70 spectroscopy targets were selected from BVRIc color magnitude diagrams for observation using the CTIO HYDRA multi-object spectrograph; we aimed to identify targets exhibiting H" in emission and a strong lithium 6708Å line in absorption. About a third of our targets (23/70 stars) are consistent with being youthful members of Coll 70. Intermediate resolution ...


Monte Carlo Simulation For Silicon On Silane Hwcvd For Thin Film Solar Cells, AnnaLeigh Smith 2014 Macalester College

Monte Carlo Simulation For Silicon On Silane Hwcvd For Thin Film Solar Cells, Annaleigh Smith

Macalester Journal of Physics and Astronomy

Thin film solar cells offer a viable alternative to crystal silicon solar cells. They are expected to be cheaper to fabricate because they use material more efficiently, and are deposited in a process which can create larger area solar cells [1]. However, a high deposition rate is necessary for economic viability. A Monte Carlo simulation can model the molecular interactions in hot wire chemical vapor deposition and track the position and velocity distribution of molecular species in the gas [2]. Determining the flux on the substrate can help us to increase deposition rate by adjusting control parameters accordingly [3]. As ...


Galaxy Merger Identification In The Goods-South Field, Erin O'Leary 2014 Macalester College

Galaxy Merger Identification In The Goods-South Field, Erin O'Leary

Macalester Journal of Physics and Astronomy

We analyzed a catalog of 7,628 galaxies at 0 < z < 4 from CANDELS1 in the GOODS-South2 field in order to identify a sample of galaxy mergers and interactions. Galaxy mergers are believed to play a fundamental role in galaxy evolution. Developing methods to robustly and efficiently identify mergers becomes vital with our increasing ability to study mergers at higher redshifts and in larger samples. We explored merger identification based on visual morphology classification and preliminary attempts with automated quantitative methods. Using multiple detailed visual morphology classifications for each galaxy conducted by the CANDELS structure and morphology team, we created selection criteria ...


Shield: Star Formation From Wiyn And Galex Imaging, Samilee J. Moody 2014 Macalester College

Shield: Star Formation From Wiyn And Galex Imaging, Samilee J. Moody

Macalester Journal of Physics and Astronomy

Using images from the GALEX (Galaxy Evolution Explorer) GR6 pipeline (released 2010), as well as the WIYN 3.5m Observatory, we present a survey of the twelve SHIELD galaxies in the far-ultraviolet (FUV, 1500 Å) and near-ultraviolet (NUV, 2200 Å) filters. FUV data were available for eleven of the galaxies, AGC 749237 being the exception. Aperture photometry was performed on each image to determine the AB magnitude in the FUV and NUV filters.These values were then used to calculate flux, luminosity, and star formation rates (SFRs). Similarly, Hα images of each galaxy from WIYN (omitting AGC 749241) were analyzed ...


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