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Data Mining By Grid Computing In The Search For Extrasolar Planets, Oisin Creaner [Thesis] 2017 Dublin Institute for Advanced Studies

Data Mining By Grid Computing In The Search For Extrasolar Planets, Oisin Creaner [Thesis]

Doctoral

A system is presented here to provide improved precision in ensemble differential photometry. This is achieved by using the power of grid computing to analyse astronomical catalogues. This produces new catalogues of optimised pointings for each star, which maximise the number and quality of reference stars available. Astronomical phenomena such as exoplanet transits and small-scale structure within quasars may be observed by means of millimagnitude photometric variability on the timescale of minutes to hours. Because of atmospheric distortion, ground-based observations of these phenomena require the use of differential photometry whereby the target is compared with one or more reference stars. …


Conference Review ‘’The Astronomy In Skyscapes - Archaeoastronomy Beyond Alignments’’. Full Day Session At The National Astronomy Meeting, University Of Nottingham (United Kingdom), 27th June–1st July, 2016, Frank Prendergast 2017 Technological University Dublin

Conference Review ‘’The Astronomy In Skyscapes - Archaeoastronomy Beyond Alignments’’. Full Day Session At The National Astronomy Meeting, University Of Nottingham (United Kingdom), 27th June–1st July, 2016, Frank Prendergast

Articles

The National Astronomy Meeting (NAM) of the Royal Astronomical Society (RAS) was held at the University of Nottingham Jubilee Campus on 27th June–1st July, 2016. This event is the primary annual scientific conference for astronomers and space scientists drawn mainly from the UK and Ireland. It is sponsored and coordinated by RAS. NAM 2016 had eight plenary talks spanning topics from planets to cosmology. Additionally, there were 60 parallel sessions broadly split into five themes, one of which was archaeoastronomy. This was the third successive NAM conference to feature a parallel session on archaeoastronomy, and was organised and chaired by …


Alignment Of The Western And Eastern Passage Tombs At Knowth Tomb 1, Frank Prendergast, Tom Ray 2017 Technological University Dublin

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.


Characterizing The Source Properties Of Terrestrial Gamma Ray Flashes, Joseph R. Dwyer, Ningyu Liu, J. Eric Grove, Hamid K. Rassoul, David M. Smith 2017 University of New Hampshire, Durham

Characterizing The Source Properties Of Terrestrial Gamma Ray Flashes, Joseph R. Dwyer, Ningyu Liu, J. Eric Grove, Hamid K. Rassoul, David M. Smith

Aerospace, Physics, and Space Science Faculty Publications

Monte Carlo simulations are used to determine source properties of terrestrial gamma ray flashes (TGFs) as a function of atmospheric column depth and beaming geometry. The total mass per unit area traversed by all the runaway electrons (i.e., the total grammage) during a TGF, Ξ, is introduced, defined to be the total distance traveled by all the runaway electrons along the electric field lines multiplied by the local air mass density along their paths. It is shown that key properties of TGFs may be directly calculated from Ξ and its time derivative, including the gamma ray emission rate, the current …


A Test Of The Interstellar Boundary Explorer Ribbon Formation In The Outer Heliosheath, Konstantin V. Gamayunov, Jacob Heerikhuisen, Hamid K. Rassoul 2017 Florida Institute of Technology

A Test Of The Interstellar Boundary Explorer Ribbon Formation In The Outer Heliosheath, Konstantin V. Gamayunov, Jacob Heerikhuisen, Hamid K. Rassoul

Aerospace, Physics, and Space Science Faculty Publications

NASA's Interstellar Boundary EXplorer (IBEX) mission is imaging energetic neutral atoms (ENAs) propagating to Earth from the outer heliosphere and local interstellar medium (LISM). A dominant feature in all ENA maps is a ribbon of enhanced fluxes that was not predicted before IBEX. While more than a dozen models of the ribbon formation have been proposed, consensus has gathered around the so-called secondary ENA model. Two classes of secondary ENA models have been proposed; the first class assumes weak scattering of the energetic pickup protons in the LISM, and the second class assumes strong but spatially localized scattering. Here we …


Possible Pair-Instability Supernovae At Solar Motallicity From Magnetic Stellar Progenitors, Cyril Georgy, Georges Meynet, Sylvia Ekström, Gregg A. Wade, Véronique Petit, Zsolt Keszthelyi, Raphael Hirschi 2017 University of Geneva

Possible Pair-Instability Supernovae At Solar Motallicity From Magnetic Stellar Progenitors, Cyril Georgy, Georges Meynet, Sylvia Ekström, Gregg A. Wade, Véronique Petit, Zsolt Keszthelyi, Raphael Hirschi

Aerospace, Physics, and Space Science Faculty Publications

Near-solar metallicity (and low-redshift) pair-instability supernova (PISN) candidates challenge stellar evolution models. Indeed, at such a metallicity, even an initially very massive star generally loses so much mass by stellar winds that it will avoid the electron-positron pair-creation instability. We use recent results showing that a magnetic field at the surface of a massive star can significantly reduce its effective mass-loss rate to compute magnetic models of very massive stars (VMSs) at solar metallicity and explore the possibility that such stars end as PISNe. We implement the quenching of the mass loss produced by a surface dipolar magnetic field into …


The Puzzling Case Of The Radio-Loud Qso 3c 186: A Gravitational Wave Recoiling Black Hole In A Young Radio Source?, Marco Chiaberge, Eric S. Perlman 2017 Johns Hopkins University

The Puzzling Case Of The Radio-Loud Qso 3c 186: A Gravitational Wave Recoiling Black Hole In A Young Radio Source?, Marco Chiaberge, Eric S. Perlman

Aerospace, Physics, and Space Science Faculty Publications

Context. Radio-loud active galactic nuclei with powerful relativistic jets are thought to be associated with rapidly spinning black holes (BHs). BH spin-up may result from a number of processes, including accretion of matter onto the BH itself, and catastrophic events such as BH-BH mergers. Aims. We study the intriguing properties of the powerful (Lbol ∼ 1047 erg s-1) radio-loud quasar 3C 186. This object shows peculiar features both in the images and in the spectra. Methods. We utilize near-IR Hubble Space Telescope (HST) images to study the properties of the host galaxy, and HST UV and Sloan Digital Sky Survey …


Studying The Photometric And Spectroscopic Variability Of The Magnetic Hot Supergiant Ζ Orionis Aa, Bram Buysschaert, Alexandre David-Uraz 2017 PSL Research University

Studying The Photometric And Spectroscopic Variability Of The Magnetic Hot Supergiant Ζ Orionis Aa, Bram Buysschaert, Alexandre David-Uraz

Aerospace, Physics, and Space Science Faculty Publications

Massive stars play a significant role in the chemical and dynamical evolution of galaxies. However, much of their variability, particularly during their evolved supergiant stage, is poorly understood. To understand the variability of evolved massive stars in more detail, we present a study of the O9.2Ib supergiant ζ Ori Aa, the only currently confirmed supergiant to host a magnetic field. We have obtained two-color space-based BRIght Target Explorer photometry (BRITE) for ζ Ori Aa during two observing campaigns, as well as simultaneous ground-based, high-resolution optical CHIRON spectroscopy. We perform a detailed frequency analysis to detect and characterize the star's periodic …


A Multi-Band Study Of The Remarkable Jet In Quasar 4c+19.44, Daniel E. Harris, Eric S. Perlman 2017 Smithsonian Astrophysical Observatory

A Multi-Band Study Of The Remarkable Jet In Quasar 4c+19.44, Daniel E. Harris, Eric S. Perlman

Aerospace, Physics, and Space Science Faculty Publications

We present arcsecond-resolution data in the radio, IR, optical, and X-ray for 4C+19.44 (=PKS 1354+195), the longest and straightest quasar jet with deep X-ray observations. We report results from radio images with half to one arcsecond angular resolution at three frequencies, plus Hubble Space Telescope and Spitzer data. The Chandra data allow us to measure the X-ray spectral index in 10 distinct regions along the 18″ jet and compare with the radio index. The radio and X-ray spectral indices of the jet regions are consistent with a value of throughout the jet, to within uncertainties. The X-ray jet structure to …


Photometric Flux In Exonest, Steven Kwun Young 2017 University at Albany, State University of New York

Photometric Flux In Exonest, Steven Kwun Young

Legacy Theses & Dissertations (2009 - 2024)

As a planet orbits its parent star, the amount of light that reaches Earth from that system is dependent on the dynamics of that star system. Known as photometric variations, these slight changes in light flux are detectable by the Kepler Space Telescope and must be fully understood in order to properly model the system. There are four main factors that contribute to the photometric flux: reflected light from the planet, thermal emissions from the planet, doppler boosting in the light being emitted by the star, and ellipsoidal variations in the star. The total observed flux from each contribution then …


A Three-Body Simulation Of Kepler-91 : A Potential Trojan System, Bryan Daniel D'Angelo 2017 University at Albany, State University of New York

A Three-Body Simulation Of Kepler-91 : A Potential Trojan System, Bryan Daniel D'Angelo

Legacy Theses & Dissertations (2009 - 2024)

This paper presents a three-body simulation of Kepler-91 (KIC 8219268) using parameters


Cancer, Alexander M. Dani 2017 Parkland College

Cancer, Alexander M. Dani

Natural Sciences Student Research Presentations

This poster for the Natural Sciences Poster Session at Parkland College features the constellation Cancer, its ten brightest stars and Messier objects. Cancer (the crab) is a zodiac constellations located between Leo and Gemini. The student identified the ten different key stars and graphed their altitudes and azimuth to calculate their lifespans. He also described the two Messier objects and calculated how many days are in a year according to the rise times of a star in the constellation.


Gemini: The Twins Of Leda, Derek Schneider 2017 Parkland College

Gemini: The Twins Of Leda, Derek Schneider

Natural Sciences Student Research Presentations

This poster for the Natural Sciences Poster Session at Parkland College features the constellation Gemini, identifying prominent stars in the constellation and objects within the region (nebulae, clusters, galaxies), calculating the lifespans of the stars in the constellation, calculating average rise time change, and briefly touching on the associated mythology.


Canis Major, Sage A. Russell 2017 Parkland College

Canis Major, Sage A. Russell

Natural Sciences Student Research Presentations

This poster for the Natural Sciences Poster Session features the constellation Canis Major. Features of the poster include a calculation of the change in rise time to calculate the passage of a year, determining the life span of the major stars in the constellation, and identifying Messier objects within the region.


On The Redshift Distribution And Physical Properties Of Act-Selected Dsfgs, T. Su, T. A. Marriage, V. Asboth, A. J. Baker, J. R. Bond, D. Crichton, M. J. Devlin, R. Dünner, D. Farrah, D. T. Frayer, M. B. Gralla, K. Hall, M. Halpern, A. I. Harris, M. Hilton, A. D. Hincks, J. P. Hughes, M. D. Niemack, L. A. Page, B. Partridge, J. Rivera, D. Scott, J. L. Sievers, Robert J. Thornton, M. P. Viero, L. Wang, E. J. Wollack, M. Zemcov 2017 Johns Hopkins University

On The Redshift Distribution And Physical Properties Of Act-Selected Dsfgs, T. Su, T. A. Marriage, V. Asboth, A. J. Baker, J. R. Bond, D. Crichton, M. J. Devlin, R. Dünner, D. Farrah, D. T. Frayer, M. B. Gralla, K. Hall, M. Halpern, A. I. Harris, M. Hilton, A. D. Hincks, J. P. Hughes, M. D. Niemack, L. A. Page, B. Partridge, J. Rivera, D. Scott, J. L. Sievers, Robert J. Thornton, M. P. Viero, L. Wang, E. J. Wollack, M. Zemcov

Physics & Engineering Faculty Publications

No abstract provided.


The Physical Properties And Composition Of Main-Belt Asteroids From Infrared Spectroscopy, Zoe Landsman 2017 University of Central Florida

The Physical Properties And Composition Of Main-Belt Asteroids From Infrared Spectroscopy, Zoe Landsman

Electronic Theses and Dissertations

Asteroids are the remnants of planet formation, and as such, they represent a record of the physical and chemical conditions in the early solar system and its evolution over the past 4.6 billion years. Asteroids are relatively accessible by spacecraft, and thus may be a source of the raw materials necessary for future human exploration and settlement of space. Those on Earth-crossing orbits pose impact hazards for which mitigation strategies must be developed. For these reasons, several missions to asteroids are in progress or planned with the support of the National Aeronautics and Space Administration (NASA) and other national space …


Using Student Characteristics, Student Spatial-Content Knowledge, And Teacher Spatial-Content Knowledge To Predict Student Spatial-Content Knowledge Of Lunar Phases, Kyle A. Curry 2017 University of Kentucky

Using Student Characteristics, Student Spatial-Content Knowledge, And Teacher Spatial-Content Knowledge To Predict Student Spatial-Content Knowledge Of Lunar Phases, Kyle A. Curry

Theses and Dissertations--Science, Technology, Engineering, and Mathematics (STEM) Education

Student demographic characteristics of gender and race/ethnicity, students’ spatial-content knowledge as measured by pre-instructional performance on the Lunar Phases Concept Inventory (LPCI) (Lindell & Olsen), and post-instructional performance on the Purdue Visualization of Rotations Test (PSVT) (Bodner & Guay, 1997), and teachers’ spatial-content knowledge as measured by the two assessments were considered to predict students’ overall understanding of lunar phases as measured by post-instructional results on the LPCI. A mixed modeling approach was used in a hierarchal manner to evaluate the student learning outcomes. Results showed that student gender was not a significant predictor of post-instructional student performance, but students …


Search For Binaries In The Kepler K2 Fields Using Pulsation Timing Method, Tomomi Otani, Terry Oswalt 2017 Embry-Riddle Aeronautical University

Search For Binaries In The Kepler K2 Fields Using Pulsation Timing Method, Tomomi Otani, Terry Oswalt

Publications

Finding orbital solutions of binaries which have small mass ratios (50 days) is challenging using traditional techniques. The radial velocity method is a good way to detect such binary stars, however it requires large telescopes. Therefore, the search for binaries in those regions is still incomplete. For binaries in this regime with at least one component that pulsates, pulsation timing is a better approach. Orbital solutions for such systems can be obtained from the periodic change in pulse arrival times as the star’s reflex motion is manifested by the changing distance along the line of sight. We present a search …


Improving Cavity Enhanced Spectroscopy Of Molecular Ions In The Mid-Infrared With Up-Conversion Detection And Brewster-Plate Spoilers, Charles R. Markus, Adam J. Perry, James N. Hodges, Benjamin J. McCall 2017 Old Dominion University

Improving Cavity Enhanced Spectroscopy Of Molecular Ions In The Mid-Infrared With Up-Conversion Detection And Brewster-Plate Spoilers, Charles R. Markus, Adam J. Perry, James N. Hodges, Benjamin J. Mccall

Chemistry & Biochemistry Faculty Publications

The performance of sensitive spectroscopic methods in the mid-IR is often limited by fringing due to parasitic etalons and the background noise in mid-infrared detectors. In particular, the technique Noise Immune Cavity Enhanced Optical Heterodyne Velocity Modulation Spectroscopy (NICE-OHVMS), which is capable of determining the frequencies of strong rovibrational transitions of molecular ions with sub-MHz uncertainty, needs improved sensitivity in order to probe weaker transitions. In this work, we have implemented up-conversion detection with NICE-OHVMS in the 3.2 - 3.9 μm region to enable the use of faster and more sensitive detectors which cover visible wavelengths. The higher bandwidth enabled …


Exomol Line List – Xxi. Nitric Oxide (No), Andy Wong, Sergei N. Yurchenko, Peter Bernath, Holger S.P. Müller, Stephanie McConkey, Jonathan Tennyson 2017 Old Dominion University

Exomol Line List – Xxi. Nitric Oxide (No), Andy Wong, Sergei N. Yurchenko, Peter Bernath, Holger S.P. Müller, Stephanie Mcconkey, Jonathan Tennyson

Chemistry & Biochemistry Faculty Publications

Line lists for the X 2Pi electronic ground state for the parent isotopologue of nitric oxide (14N16O) and five other major isotopologues (14N17O, 14N18O, 15N16O, 15N17O and 15N18O) are presented. The line lists are constructed using empirical energy levels (and line positions) and high-level ab initio intensities. The energy levels were obtained using a combination of two approaches, from an effective Hamiltonian and from solving the rovibronic Schrödinger equation variationally. The effective Hamiltonian model was obtained through a fit …


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