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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.


Tracing The Origin Of Presolar Grains: Algorithms To Parametrize Supernovae, Justin M. Finkel 2014 Washington University in St. Louis

Tracing The Origin Of Presolar Grains: Algorithms To Parametrize Supernovae, Justin M. Finkel

Undergraduate Research Symposium Posters & Abstracts

Certain meteorites contain grains of stardust with isotopic compositions that suggest supernova origins. Furthermore, individual grains often contain signatures from different zones of the star, from the iron-rich core to the hydrogen- and helium-rich envelope. This implies large-scale mixing between layers, and a grain’s specific combination of isotopic ratios can be used to constrain these mixing mechanisms. To this end we have developed an algorithm which, given a grain’s set of measured isotopic ratios and a theoretical supernova model, assigns ‘mixing fractions’ to various zones of the supernova, indicating what fraction of the grain comes from each zone ...


Characterizing New Calibration Sources In Liquid Xenon Dark Matter Searches, Evan P. Bray, Rafael Lang, Sean MacMullin 2014 Purdue University

Characterizing New Calibration Sources In Liquid Xenon Dark Matter Searches, Evan P. Bray, Rafael Lang, Sean Macmullin

The Summer Undergraduate Research Fellowship (SURF) Symposium

In order to use the XENON1T liquid xenon detector as a means for detecting dark matter, the response to nuclear and electronic recoils must be well calibrated. Electronic-recoil calibration of XENON1T will be done by using the noble gas radon-220 that emanates from a custom thorium-228 source to observe the electron recoils that its daughter elements induce in liquid xenon. A silicon PIN diode was constructed to ensure that the Th228 source does not contaminate the system with the long-lived isotopes Th228 (T1/2 of 1.9 y) or Radium-224 (T1/2 of 3.6 d). The PIN diode was ...


The Role Of Subsurface Flows In Solar Surface Convection: Modeling The Spectrum Of Supergranular And Larger Scale Flows, J. W. Lord, R. H. Cameron, M. P. Rast, M. Rempel, T. Roudier 2014 University of Colorado, Boulder

The Role Of Subsurface Flows In Solar Surface Convection: Modeling The Spectrum Of Supergranular And Larger Scale Flows, J. W. Lord, R. H. Cameron, M. P. Rast, M. Rempel, T. Roudier

Astrophysical & Planetary Sciences Faculty Contributions

We model the solar horizontal velocity power spectrum at scales larger than granulation using a two-component approximation to the mass continuity equation. The model takes four times the density scale height as the integral (driving) scale of the vertical motions at each depth. Scales larger than this decay with height from the deeper layers. Those smaller are assumed to follow a Kolmogorov turbulent cascade, with the total power in the vertical convective motions matching that required to transport the solar luminosity in a mixing length formulation. These model components are validated using large-scale radiative hydrodynamic simulations. We reach two primary ...


2014 Scas Annual Meeting Program, 2014 University of South Carolina

2014 Scas Annual Meeting Program

Journal of the South Carolina Academy of Science

No abstract provided.


Scas Officers And Council Members 2014-2015, 2014 University of South Carolina

Scas Officers And Council Members 2014-2015

Journal of the South Carolina Academy of Science

No abstract provided.


Table Of Contents, 2014 University of South Carolina

Table Of Contents

Journal of the South Carolina Academy of Science

No abstract provided.


Intensities, Broadening And Narrowing Parameters In The Ν3 Band Of Methane, Et-touhami Es-sebbar, Aamir Farooq 2014 SelectedWorks

Intensities, Broadening And Narrowing Parameters In The Ν3 Band Of Methane, Et-Touhami Es-Sebbar, Aamir Farooq

Dr. Et-touhami Es-sebbar

The P-branch of methane׳s ν3 band is probed to carry out an extensive study of the 2905–2908 cm−1 infrared spectral region. Absolute line intensities as well as N2-, O2-, H2-, He-, Ar- and CO2-broadening coefficients are determined for nine transitions at room temperature. Narrowing parameters due to the Dicke effect have also been investigated. A narrow emission line-width (~0.0001 cm−1) difference-frequency-generation (DFG) laser system is used as the tunable light source. To retrieve the CH4 spectroscopic parameters, Voigt and Galatry profiles were used to simulate the measured line shape of the individual transitions.


The Meaning Of Wise Colours – I. The Galaxy And Its Satellites, Robert Nikutta, Nicholas Hunt-Walker, Maia M. Nenkova, Željko Ivezić, Moshe Elitzur 2014 University of Kentucky

The Meaning Of Wise Colours – I. The Galaxy And Its Satellites, Robert Nikutta, Nicholas Hunt-Walker, Maia M. Nenkova, Željko Ivezić, Moshe Elitzur

Physics and Astronomy Faculty Publications

Through matches with the Sloan Digital Sky Survey (SDSS) catalogue we identify the location of various families of astronomical objects in WISE colour space. We identify reliable indicators that separate Galactic/local from extragalactic sources and concentrate here on the objects in our Galaxy and its closest satellites. We develop colour and magnitude criteria that are based only on WISE data to select asymptotic giant branch (AGB) stars with circumstellar dust shells, and separate them into O-rich and C-rich classes. With these criteria we produce an all-sky map for the count ratio of the two populations. The map reveals differences ...


Observational Signatures From Self-Gravitating Protostellar Disks, Alexander L. DeSouza 2014 Western University

Observational Signatures From Self-Gravitating Protostellar Disks, Alexander L. Desouza

University of Western Ontario - Electronic Thesis and Dissertation Repository

Protostellar disks are the ubiquitous corollary outcome of the angular momentum conserving, gravitational collapse of molecular cloud cores into stars. Disks are an essential component of the star formation process, mediating the accretion of material onto the protostar, and for redistributing excess angular momentum during the collapse. We present a model to explain the observed correlation between mass accretion rates and stellar mass that has been inferred from observations of intermediate to upper mass T Tauri stars. We explain this correlation within the framework of gravitationally driven torques parameterized in terms of Toomre’s Q criterion. Our models reproduce both ...


Measuring Noble Gases In Coma Samples From Comet Wild 2, Jacob Simones 2014 Minnesota State University, Mankato

Measuring Noble Gases In Coma Samples From Comet Wild 2, Jacob Simones

Journal of Undergraduate Research at Minnesota State University, Mankato

Since comets originated during the formation of the solar system, the processes of solar system formation can be better understood through compositional analysis of cometary material. A low density, silicon-based substance called aerogel was used by NASA’s Stardust spacecraft to collect coma samples from comet Wild 2. Aerogel not from the spacecraft (“non-flight”) was investigated to determine the possibility of measuring noble gases in Stardust samples. Gas evolved from heated, non-flight aerogel was measured initially using a residual gas analyzer, then a high-sensitivity massspectrometer. Levels of helium and neon isotopes observed from both instruments were sufficiently low that noble ...


Automated Image Interpretation For Science Autonomy In Robotic Planetary Exploration, Raymond Francis 2014 Western University

Automated Image Interpretation For Science Autonomy In Robotic Planetary Exploration, Raymond Francis

University of Western Ontario - Electronic Thesis and Dissertation Repository

Advances in the capabilities of robotic planetary exploration missions have increased the wealth of scientific data they produce, presenting challenges for mission science and operations imposed by the limits of interplanetary radio communications. These data budget pressures can be relieved by increased robotic autonomy, both for onboard operations tasks and for decision- making in response to science data.

This thesis presents new techniques in automated image interpretation for natural scenes of relevance to planetary science and exploration, and elaborates autonomy scenarios under which they could be used to extend the reach and performance of exploration missions on planetary surfaces.

Two ...


An Analysis Of The Location Of White Light Flares In The Sun's Atmosphere, Michelle D. Wilbur 2014 California Polytechnic State University

An Analysis Of The Location Of White Light Flares In The Sun's Atmosphere, Michelle D. Wilbur

STEM Teacher and Researcher (STAR) Program Posters

When flares occur in the Sun’s atmosphere, electromagnetic radiation in all wavelengths is emitted. Flares observed at visible wavelengths are called "white light" flares. Little is known about white light flares since the radiation from the Sun in the visible range greatly outshines what is produced during solar flares. Since white light flares are hard to see, it is not clear in what part of the solar atmosphere they occur. The point of this research is to identify where in the corona white light emission in produced during a flare. Depending on what will be discovered affects the validity ...


Maximizing Precision Of Variable Star Photometry With Digital Cameras In Suburban Environments, David Hergesheimer 2014 California Polytechnic State University

Maximizing Precision Of Variable Star Photometry With Digital Cameras In Suburban Environments, David Hergesheimer

STEM Teacher and Researcher (STAR) Program Posters

Photometry is the measure of the brightness of an object. When making such measurements on stars, it is done is units of magnitude, which is on a logarithmic scale with a base of ~2.512. Variable star photometry using a commercially available digital camera is not going to be as accurate and precise as equipment used by astronomers, and because of the logarithmic scale of magnitude used, determining how much of an effect different error reduction strategies have is not straightforward, and is best done experimentally.

My research is conducting photometry on variable stars (changing brightness) with a digital camera ...


Phylogenetic Diversity Of Microbial Isolates From The Mars Pathfinder, Kyla BradyLong, Adriana Blachowicz, Parag Vaishampayan, James N. Benardini, Wayne Schubert 2014 California Polytechnic State University

Phylogenetic Diversity Of Microbial Isolates From The Mars Pathfinder, Kyla Bradylong, Adriana Blachowicz, Parag Vaishampayan, James N. Benardini, Wayne Schubert

STEM Teacher and Researcher (STAR) Program Posters

As spacecraft are sent to different planets, they take with them microscopic pieces of life from Earth. It is the task of the Biotechnology and Planetary Protection Group to keep as much of this life off other planets as possible as well as document any life that may have been sent. During the construction of the Mars Pathfinder, samples were collected from various locations on the spacecraft to test for contamination. These samples were then isolated, grown, documented, preserved and their 16S rRNA genes were sequenced for identification. The 16S rRNA gene sequence is utilized because it is a highly ...


Environmental Testing Of Lasers For Jpl's Cold Atom Laboratory, Carey L. Baxter 2014 California Polytechnic State University

Environmental Testing Of Lasers For Jpl's Cold Atom Laboratory, Carey L. Baxter

STEM Teacher and Researcher (STAR) Program Posters

NASA’s Cold Atom Lab (CAL) is a multi-user facility designed to study ultra-cold quantum gases in the microgravity environment of the International Space Station (ISS). One of the main goals of CAL is to explore the unknown territory of extremely low temperatures—possibly as low as the picokelvin range!—where new and fascinating quantum phenomena can be observed. At such temperatures matter stops behaving as particles and instead becomes macroscopic matter waves. CAL will be remotely controlled to perform a multitude of experiments and is scheduled to launch in 2016. In order to anticipate problems that might occur during ...


Laser Frequency Stabilization For Lisa, Andrew B. Parker, Andrew J. Sutton, Glenn De Vine 2014 California Polytechnic State University

Laser Frequency Stabilization For Lisa, Andrew B. Parker, Andrew J. Sutton, Glenn De Vine

STEM Teacher and Researcher (STAR) Program Posters

This research focuses on laser ranging developments for LISA (Laser Interferometer Space Antenna), a planned NASA-ESA gravitational wave detector in space. LISA will utilize precision laser interferometry to track the changes in separation between three satellites orbiting 5 million kilometers apart. Specifically, our goal is to investigate options for laser frequency stabilization. Previous research has shown that an optical cavity system can meet LISA's stability requirements, but these units are large and heavy, adding cost to the implementation. A heterodyne Mach-Zehnder interferometer could be integrated onto LISA’s existing optical bench, greatly reducing the weight, provided the interferometer meets ...


Measuring K-Shell Transitions In L-Shell Ions Of Aluminum Using Llnl Ebit, Grecia Ramos 2014 California Polytechnic State University

Measuring K-Shell Transitions In L-Shell Ions Of Aluminum Using Llnl Ebit, Grecia Ramos

STEM Teacher and Researcher (STAR) Program Posters

We measured the transition energies of the 1s-2p Kα transitions in Al4+ through Al11+. The aluminum ions were created and trapped using the LLNL’s Electron Beam Ion Trap (EBIT). Once created and trapped, upper levels were collisionally excited by electrons in EBIT's electron beam. X-ray emission following radiative decay of excited levels was detected using the EBIT Calorimeter Spectrometer (ECS). We have measured the centroids of the strongest lines to an accuracy of less than 1 eV. These results will be used to properly identify line emission from celestial x-ray sources, such as elliptical galaxy NGC 4472 and ...


Light Pollution Research Through Citizen Science, John Kanemoto 2014 California Polytechnic State University

Light Pollution Research Through Citizen Science, John Kanemoto

STEM Teacher and Researcher (STAR) Program Posters

Light pollution (LP) can disrupt and/or degrade the health of all living things, as well as, their environments. The goal of my research at the NOAO was to check the accuracy of the citizen science LP reporting systems entitled: Globe at Night (GaN), Dark Sky Meter (DSM), and Loss of the Night (LoN). On the GaN webpage, the darkness of the night sky (DotNS) is reported by selecting a magnitude chart. Each magnitude chart has a different density/number of stars around a specific constellation. The greater number of stars implies a darker night sky. Within the DSM iPhone ...


Hunting Starstuff: Searching For Calcium-Aluminum-Rich Inclusions In Cometary Dust, Christian Engelbrecht 2014 California Polytechnic State University

Hunting Starstuff: Searching For Calcium-Aluminum-Rich Inclusions In Cometary Dust, Christian Engelbrecht

STEM Teacher and Researcher (STAR) Program Posters

NASA’s Stardust mission (1999 - 2006) returned physical samples of the particles ejected by the comet 81P/Wild 2, collected in ultralight and extremely low density aerogel. These samples have been extensively analyzed using X-Ray Fluorescence (XRF), among other techniques, to determine the elemental, chemical and mineralogical composition of Wild 2. Because comets are thought to be formed in the icy outer regions of the solar system, billions of years ago, the Stardust data gives us details of the composition of the ancient solar system and its subsequent evolution. One of the surprises to come out of the data is ...


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