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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.


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 ...


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 ...


Observing Magnetic Fields And Currents At The Night And Terminator Sides Of Mars Through The Mars Global Surveyor Data, Nicole Ponce, Matthey Fillingim, Alexander Fogle 2014 California Polytechnic State University

Observing Magnetic Fields And Currents At The Night And Terminator Sides Of Mars Through The Mars Global Surveyor Data, Nicole Ponce, Matthey Fillingim, Alexander Fogle

STEM Teacher and Researcher (STAR) Program Posters

Mars has no global magnetic field. Changes in the solar wind and interplanetary magnetic field (IMF) can impact the upper atmosphere and induce currents in the ionosphere of Mars. During aerobraking maneuvers, Mars Global Surveyor (MGS) made over 1000 passes through Mars’s ionosphere. During these passes, MGS measured the local magnetic field. From these measurements, we can determine the ionospheric currents. We restrict our analysis to passes where the radial component of the magnetic field is nearly zero. This restriction, along with some assumptions about the gradients in the magnetic field, allows us to estimate the horizontal ionospheric currents ...


The Magnetopause: Bringing Space Physics Into A Junior Lab, Jim Crumley, Ari Palczewski,, Stephen Kaster 2014 College of Saint Benedict and Saint John’s University

The Magnetopause: Bringing Space Physics Into A Junior Lab, Jim Crumley, Ari Palczewski,, Stephen Kaster

MapCores Faculty Publications

Undergraduate students often have minimal exposure to many subfields
of physics which are active areas of research. Space physics
is an area that is particularly difficult to expose students to since
it builds off of another area that most undergraduates see little of,
plasma physics. The magnetopause is convenient entry point
into space physics, since it can be modeled as a pressure balance, which is
a concept familiar from introductory physics. We use the Earth's
magnetopause as the basis for a lab for junior physics majors. In
the lab students analyze results from a NASA MHD simulation and
data ...


Static Interaction Of Black Holes In 1+1 Dimensions, Philip Greenwood 2014 California Polytechnic State University

Static Interaction Of Black Holes In 1+1 Dimensions, Philip Greenwood

Physics

We consider a version of general relativity in two spacetime dimensions, and

study a solution describing two static black holes in the presence of a cosmological

constant. We first analytically find an embedding diagram to visualize the geometry

outside the black holes. We then examine how the two black holes must be

interacting to remain static. Our main result is to show how the black holes behave

effectively like two electric charges. This charge model exhibits both attraction and

repulsion, which evidently balance and moreover are localized in different regions

of space. We also begin an investigation of the black ...


Report On The Workshop For Life Detection In Samples From Mars, Gerhard Kminek, Catherine Conley, Carlton C. Allen, Douglas H. Bartlett, David W. Beaty, Liane G. Benning, Rohit Bhartia, Penelope J. Boston, Caroline Duchaine, Jack D. Farmer, George J. Flynn, Daniel P. Glavin, Yuri Gorby, John E. Hallsworth, Rakesh Mogul, Duane Moser, P. Buford Price, Ruediger Pukall, David Fernandez-Remolar, Caroline L. Smith, Kenneth M. Stedman, Andrew Steele, Ramunas Stepanauskas, Henry Sun, Jorge L. Vago, Mary A. Voytek, Paul S. Weiss, Frances Westfall 2014 Portland State University

Report On The Workshop For Life Detection In Samples From Mars, Gerhard Kminek, Catherine Conley, Carlton C. Allen, Douglas H. Bartlett, David W. Beaty, Liane G. Benning, Rohit Bhartia, Penelope J. Boston, Caroline Duchaine, Jack D. Farmer, George J. Flynn, Daniel P. Glavin, Yuri Gorby, John E. Hallsworth, Rakesh Mogul, Duane Moser, P. Buford Price, Ruediger Pukall, David Fernandez-Remolar, Caroline L. Smith, Kenneth M. Stedman, Andrew Steele, Ramunas Stepanauskas, Henry Sun, Jorge L. Vago, Mary A. Voytek, Paul S. Weiss, Frances Westfall

Biology Faculty Publications and Presentations

The question of whether there is or was life on Mars has been one of the most pivotal since Schiaparellis’ telescopic observations of the red planet. With the advent of the space age, this question can be addressed directly by exploring the surface of Mars and by bringing samples to Earth for analysis. The latter, however, is not free of problems. Life can be found virtually everywhere on Earth. Hence the potential for contaminating the Mars samples and compromising their scientific integrity is not negligible. Conversely, if life is present in samples from Mars, this may represent a potential source ...


Observational And Theoretical Investigation Of Cylindrical Line Source Blast Theory Using Meteors, Elizabeth A. Silber 2014 Western University

Observational And Theoretical Investigation Of Cylindrical Line Source Blast Theory Using Meteors, Elizabeth A. Silber

University of Western Ontario - Electronic Thesis and Dissertation Repository

During their passage through the atmosphere meteoroids produce a hypersonic shock which may be recorded at the ground in the form of infrasound. The first objective of this project was to use global infrasound measurements to estimate the influx of large (meter/decameter) objects to Earth and investigate which parameters of their ablation and disruption can be determined using infrasound records. A second objective was to evaluate and extend existing cylindrical line source blast theory for meteoroids by combining new observations with earlier analytical models, and validate these against centimetre-sized optical meteor observations.

The annual terrestrial influx of large meteoroids ...


Cosmic Sound In The Lyman Alpha Forest, Spencer Everett, Matt Kwiecien, Cordell Newmiller 2014 DePaul University

Cosmic Sound In The Lyman Alpha Forest, Spencer Everett, Matt Kwiecien, Cordell Newmiller

DePaul Discoveries

Using the Baryon Oscillation Spectroscopic Survey (BOSS) from the Sloan Digital Sky Survey (SDSS), the authors attempt to detect the baryonic acoustic oscillations (BAOs) using the discrete wavelet transform. The wavelet transform is used to construct the power spectrum of intergalactic clouds of matter at large (Mpc) distance scales. It was found that the wavelet transform used here does not have high enough resolution to detect the BAOs. However, the techniques used in this study allow for future improvements in the transform that could potentially resolve the expected peak in the power spectrum and indicate the existence of BAOs.


The Evolution Of And Starburst-Agn Connection In Luminous And Ultraluminous Infrared Galaxies And Their Link To Globular Cluster Formation, Stephanie L. Fiorenza 2014 The Graduate Center, CUNY

The Evolution Of And Starburst-Agn Connection In Luminous And Ultraluminous Infrared Galaxies And Their Link To Globular Cluster Formation, Stephanie L. Fiorenza

Dissertations and Theses, 2014-Present

The evolutionary connection between nuclear starbursts and active galactic nuclei (AGN) in luminous infrared galaxies (LIRGs; 1011o

Using new spectrophotometric data, I classify the primary source of IR radiation as being a nuclear starburst or a type of AGN by using the Baldwin-Phillips-Terlevich (BPT) diagrams. I show that for the U/LIRGs in my sample the properties that describe their nuclear starbursts and AGN (e.g. star formation rate (SFR), L[O III], optical D parameter, D4000, and EW(Hδ)) are independent of one another, ensuring that no biases affect correlations between these properties and objects' locations on the BPT ...


On The Observability Of Optically Thin Coronal Hyperfine Structure Lines, Marios Chatzikos, Gary Ferland, R. J. R. Williams, A. C. Fabian 2014 University of Kentucky

On The Observability Of Optically Thin Coronal Hyperfine Structure Lines, Marios Chatzikos, Gary Ferland, R. J. R. Williams, A. C. Fabian

Physics and Astronomy Faculty Publications

We present CLOUDY calculations for the intensity of coronal hyperfine lines in various environments. We model indirect collisional and radiative transitions, and quantify the collisionally excited line emissivity in the density-temperature phase space. As an observational aid, we also express the emissivity in units of that in the 0.4-0.7 keV band. For most hyperfine lines, knowledge of the X-ray surface brightness and the plasma temperature is sufficient for rough estimates. We find that the radiation fields of both Perseus A and Virgo A can enhance the populations of highly ionized species within 1 kpc. They can also enhance ...


Veritas Very High Energy Observations Of The Distant Blazar 1es 0647+250, Margaret R. Molter, Jon Dumm, Lucy Fortson 2014 Macalester College

Veritas Very High Energy Observations Of The Distant Blazar 1es 0647+250, Margaret R. Molter, Jon Dumm, Lucy Fortson

Macalester Journal of Physics and Astronomy

We perform an analysis of the long- and short-term variability of the very high energy (VHE; above 100 GeV) gamma-ray emission from the newly-detected distant blazar 1ES 0647+250. Both new and archival data from the VERITAS telescope were examined, and no strong evidence for integral flux variability on any timescale was found. This lack of variability is consistent with the application of current ultra-high energy cosmic ray (UHECR) models, which can produce secondary gamma-ray emission along the line of sight from the blazar; it also allows averaging over multiyear timescales without bias, aiding in the construction of spectral energy ...


Finesse Measurement In Fabry-Perot Interferometers, Michael C. Darrow 2014 Macalester College

Finesse Measurement In Fabry-Perot Interferometers, Michael C. Darrow

Macalester Journal of Physics and Astronomy

STAR (Space-time Asymmetry Research) is an experimental satellite that will measure anisotropy in the speed of light to unprecedented resolutions using two orthogonal Fabry- Perot interferometers. In order to achieve the desired level of precision, the optical cavities must have finesse values greater than 100,000. Using two test interferometers, I tested and optimized two different experimental methods for measurement of finesse: full-width half max measurement and cavity ring-down spectroscopy. Although each technique proved valid in its own right, my work suggests that cavity ring-down spectroscopy may be more applicable for the needs of STAR.


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