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Fuor And Exor Variables: A Nir High-Resolution Spectroscopic Survey, Joseph Liskowsky 2010 Clemson University

Fuor And Exor Variables: A Nir High-Resolution Spectroscopic Survey, Joseph Liskowsky

All Theses

To better understand the labyrinth of heating and cooling processes in YSOs (young stellar objects), we study systems where there exists a large variability in the heating of this gas due to accretion. This research project focuses on several classes of early young eruptable T-Tauri stars, namely the FUors, the EXors and the so-called FU Ori-like, which all have the property of large amplitude oscillations in accretion rate. Each of these categories may well represent specific stages in early low-mass stellar evolution. While these objects have specific spectroscopic and circumstellar diagnostics (as means of identification) our research suggests that there …


A Brief History And Research Of The Supernova Remnant Cassiopeia A, Michelle Wilbur 2010 California Polytechnic State University - San Luis Obispo

A Brief History And Research Of The Supernova Remnant Cassiopeia A, Michelle Wilbur

Physics

No abstract provided.


Exoplanet Transit Detection With Terrestrial Amateur Equipment: Using The Cal Poly Observatory, San Luis Obispo, Joshua Thompson 2010 California Polytechnic State University - San Luis Obispo

Exoplanet Transit Detection With Terrestrial Amateur Equipment: Using The Cal Poly Observatory, San Luis Obispo, Joshua Thompson

Physics

Using amateur level equipment and freeware analysis tools, the Cal Poly Observatory (CPO) wished to test whether or not it could actually observe the astronomical phenomena called exoplanetary transits. Using a variety of equipment and tests, the CPO was able to confirm it could clearly observe the transits of several well-known transiting planets, including HD189733b and HAT-P-6. With these tests and observations completed, future student researchers can continue Cal Poly’s transit search and contribute to the global pursuit for exoplanets.


Abrupt Longitudinal Magnetic Field Changes In Flaring Active Regions, G. J.D. Petrie, Jeffrey J. Sudol 2010 National Solar Observatory

Abrupt Longitudinal Magnetic Field Changes In Flaring Active Regions, G. J.D. Petrie, Jeffrey J. Sudol

Physics & Engineering Faculty Publications

No abstract provided.


Gravity Couplings In The Standard-Model Extension, Quentin G. Bailey 2010 Embry-Riddle Aeronautical University

Gravity Couplings In The Standard-Model Extension, Quentin G. Bailey

Publications

The Standard-Model Extension (SME) is an action-based expansion describing general Lorentz violation for known matter and fields, including gravity. In this talk, I will discuss the Lorentz-violating gravity couplings in the SME. Toy models that match the SME expansion, including vector and two-tensor models, are reviewed. Finally I discuss the status of experiments and observations probing gravity coefficients for Lorentz violation.


Bianchi Type I Magnetized Cosmological Model In Bimetric Theory Of Gravitation, M. S. Borkar, S. S. Charjan 2010 R. T. M. Nagpur University

Bianchi Type I Magnetized Cosmological Model In Bimetric Theory Of Gravitation, M. S. Borkar, S. S. Charjan

Applications and Applied Mathematics: An International Journal (AAM)

In this paper, we attempt to construct a Bianchi Type I magnetized cosmological model in Rosen’s bimetric theory of gravitation by using the techniques of Letelier and Stachel under the condition that ABCn , where n  0 in Rosen’s field equations. The physical and geometrical significance of the model are discussed. It is important to note the added dimension of this paper include the introduction of a magnetic field on the model. Prior to this, all it has been is a vacuum model in bimetric gravitation.


Comparison Of H-Alpha And H-Beta Temperature Indices In The Hyades And Coma Star Clusters And Selected H-Beta Standard Stars, Miriam Anne West 2010 Brigham Young University - Provo

Comparison Of H-Alpha And H-Beta Temperature Indices In The Hyades And Coma Star Clusters And Selected H-Beta Standard Stars, Miriam Anne West

Theses and Dissertations

Using the Dominion Astrophysical Observatory's 1.2-m McKellar Telescope, we have obtained spectra on 81 stars from the Hyades Cluster, the Coma Cluster, and selected H-beta standard stars. These spectra cover from 4500 Å to 6900 Å which includes both the H-β and H-α absorption lines. The H-β absorption line has a long history of being used as a temperature index and more recently, calibration of an H-α index has been established for photometric observations. Through spectrophotometric comparison of temperature indices from the H-α and H-β absorption lines we find the expected strong correlation between photometric indices based on the strength …


The Interaction Of Rock And Water During Shock Decompression: A Hybrid Model For Fluidized Ejecta Formation, Audrey Hughes Rager 2010 University of Nevada, Las Vegas

The Interaction Of Rock And Water During Shock Decompression: A Hybrid Model For Fluidized Ejecta Formation, Audrey Hughes Rager

UNLV Theses, Dissertations, Professional Papers, and Capstones

Crater and ejecta morphology provide insight into the composition and structure of the target material. Martian rampart craters, with their unusual single-layered (SLE), double-layered (DLE), and multi-layered ejecta (MLE), are the subject of particular interest among planetary geologists because these morphologies are thought to result from the presence of water in the target. Also of interest are radial lines extending from the crater rim to the distal rampart of DLE craters. Exactly how these layered ejecta morphologies and radial lines form is not known, but they are generally thought to result from interaction of the ejecta with the atmosphere, subsurface …


Modeling The Galactic 511 Kev Positron Annihilation Emission, Production, And Propagation, Bethany Johns 2010 Clemson University

Modeling The Galactic 511 Kev Positron Annihilation Emission, Production, And Propagation, Bethany Johns

All Dissertations

The Galactic 511 keV positron annihilation emission has a strong bulge component to the emission and a weak disk component. The bulge emission is about 1.4 -- 6 times as the disk emission. The bulge emission is defined to be a diffuse emission centered at the Galactic center and extends to about a FWHM of 8 degrees in Galactic longitude and latitude. An asymmetry has also been observed in the disk emission, where the negative longitudes are brighter than the positive longitudes by a factor of 1.8.
This research examines the morphology of the Galactic 511 keV positron annihilation emission …


Gamma Ray Bursts As Probes Of Dust In The Evolving Universe, Adria Updike 2010 Clemson University

Gamma Ray Bursts As Probes Of Dust In The Evolving Universe, Adria Updike

All Dissertations

Dust is ubiquitous in the universe. Understanding where it comes from and where we observe it can have major implications to all astronomical observations. In this study, we investigate how gamma ray bursts (GRBs) can be used as probes of dust in the evolving universe. Making the simplification that silicate dust comes from core collapse supernovae and that graphite dust is produced in the winds of low- to intermediate-mass stars, we present numerical simulations of the resulting dust evolution in GRB hosts and show how the SEDs evolve. Dust extinction laws are re-derived from scattering theory of small particles and …


Design, Manufacturing, And Commissioning Of Bircam (Bootes Infrared Camera), Alberto Riva, Paolo Conconi, Alberto Javier Castro-Tirado, Filippo Zerbi, Ronan Cunniffe, Martin Jelinek, Stanislav Vitek 2010 Osservatorio Astronomico di Torino

Design, Manufacturing, And Commissioning Of Bircam (Bootes Infrared Camera), Alberto Riva, Paolo Conconi, Alberto Javier Castro-Tirado, Filippo Zerbi, Ronan Cunniffe, Martin Jelinek, Stanislav Vitek

Blackrock Castle Observatory Publications

This paper covers the various aspect of design, manufacturing and commissioning of the infrared camera BIRCAM, installed at BOOTES-IR, the 60 cm robotic infrared telescope at Sierra Nevada Observatory (OSN, Granada, Spain). We describe how we achieved a quality astronomical image, moving from the scientific requirements.


The Carter Constant For Inclined Orbits About A Massive Kerr Black Hole: I. Circular Orbits, Peter G. Komorowski, Sree Ram Valluri, Martin Houde 2010 The University of Western Ontario

The Carter Constant For Inclined Orbits About A Massive Kerr Black Hole: I. Circular Orbits, Peter G. Komorowski, Sree Ram Valluri, Martin Houde

Physics and Astronomy Publications

In an extreme binary black hole system, an orbit will increase its angle of inclination (ι) as it evolves in Kerr spacetime. We focus our attention on the behaviour of the Carter constant (Q) for near-polar orbits, and develop an analysis that is independent of and complements radiation-reactionmodels. For a Schwarzschild black hole, the polar orbits represent the abutment between the prograde and retrograde orbits at whichQis at its maximum value for given values of the latus rectum (˜l ) and the eccentricity (e). The introduction of spin (S˜ = |J|/M2) to themassive black hole causes this boundary, or abutment, …


Search For Gravitational Waves From Compact Binary Coalescence In Ligo And Virgo Data From S5 And Vsr1, J. Abadie, B. P. Abbott, R. Abbott, M. Abernathy, T. Accadia, F. Acernese, C. Adams, R. Adhikari, P. Ajith, B. Allen, G. Allen, E. Amador Ceron, R. S. Amin, S. B. Anderson, W. G. Anderson, F. Antonucci, M. A. Arain, M. Araya, M. Aronsson, K. G. Arun, Y. Aso, S. Aston, P. Astone, D. E. Atkinson, P. Aufmuth, C. Aulbert, S. Babak, P. Baker, G. Ballardin, T. Ballinger, S. Ballmer, Tiffany Z. Summerscales 2010 California Institute of Technology

Search For Gravitational Waves From Compact Binary Coalescence In Ligo And Virgo Data From S5 And Vsr1, J. Abadie, B. P. Abbott, R. Abbott, M. Abernathy, T. Accadia, F. Acernese, C. Adams, R. Adhikari, P. Ajith, B. Allen, G. Allen, E. Amador Ceron, R. S. Amin, S. B. Anderson, W. G. Anderson, F. Antonucci, M. A. Arain, M. Araya, M. Aronsson, K. G. Arun, Y. Aso, S. Aston, P. Astone, D. E. Atkinson, P. Aufmuth, C. Aulbert, S. Babak, P. Baker, G. Ballardin, T. Ballinger, S. Ballmer, Tiffany Z. Summerscales

Faculty Publications

We report the results of the first search for gravitational waves from compact binary coalescence using data from the Laser Interferometer Gravitational-Wave Observatory and Virgo detectors. Five months of data were collected during the Laser Interferometer Gravitational-Wave Observatory's S5 and Virgo's VSR1 science runs. The search focused on signals from binary mergers with a total mass between 2 and 35M□. No gravitational waves are identified. The cumulative 90%-confidence upper limits on the rate of compact binary coalescence are calculated for nonspinning binary neutron stars, black hole-neutron star systems, and binary black holes to be 8.7×10⊃- 3yr⊃-1L10-1, 2.2×10⊃-3yr⊃-1L10-1, and 4.4×10⊃- 4yr⊃-1L10-1, …


Tuning The Morphology Of Au/Cds Nanocomposites Through Temperature-Controlled Reduction Of Gold-Oleate Complexes, Elena Khon, Nishshanka N. Hewa-Kasakarage, Ian Nemitz, Krishna Acharya, Mikhail Zamkov 2010 Bowling Green State University

Tuning The Morphology Of Au/Cds Nanocomposites Through Temperature-Controlled Reduction Of Gold-Oleate Complexes, Elena Khon, Nishshanka N. Hewa-Kasakarage, Ian Nemitz, Krishna Acharya, Mikhail Zamkov

Physics and Astronomy Faculty Publications

A general synthetic strategy for controlling the shape of gold domains grown onto CdS semiconductor nanocrystals is presented. The colloidal growth of Au nanoparticles is based on the temperature-controlled reduction of Au-oleate complexes on the surface of CdS and allows for precise tuning of nanoparticle diameters from 2.5 to 16 nm simply by adjusting the temperature of the growth solution, whereas the shape of Au/CdS nanocomposites can be controllably switched between matchsticks and barbells via the reaction rate. Depending on the exact morphology of Au and CdS domains, fabricated nanocomposites can undergo evaporation-induced self-assembly on a substrate either through end-to-end …


Δ Sct-Type Pulsations In Eclipsing Binary Systems: Y Cam, E. Rodriguez, J. M. Garcia, V. Costa, P. Lampens, P. J. Amado, J. Daszynska-Daszkiewicz, V. Turcu, S.-L. Kim, A. Y. Zhou, M. J. Lopez-Gonzalez, A. Rolland, D. Diaz-Fraile, M. A. Wood 2010 Florida Institute of Technology

Δ Sct-Type Pulsations In Eclipsing Binary Systems: Y Cam, E. Rodriguez, J. M. Garcia, V. Costa, P. Lampens, P. J. Amado, J. Daszynska-Daszkiewicz, V. Turcu, S.-L. Kim, A. Y. Zhou, M. J. Lopez-Gonzalez, A. Rolland, D. Diaz-Fraile, M. A. Wood

Aerospace, Physics, and Space Science Faculty Publications

We present the results of a three-continent multisite photometric campaign carried out on the Algol-type eclipsing binary system Y Cam, in which the primary component is a multiperiodic δ Sct-type pulsator. The observations consist of 86 nights and more than 450 h of useful data collected mainly during the Northern winter 2002–2003. This means that this is the most extensive time series for such kind of systems obtained so far. These observations were collected mostly in the Johnson V filter, but they also include, for the first time, nearly complete binary light curves in simultaneous Strömgren uvby filters together with …


Structure And Feedback In 30 Doradus. I. Observations, E. W. Pellegrini, J. A. Baldwin, Gary J. Ferland 2010 University of Michigan

Structure And Feedback In 30 Doradus. I. Observations, E. W. Pellegrini, J. A. Baldwin, Gary J. Ferland

Physics and Astronomy Faculty Publications

We have completed a new optical imaging and spectrophotometric survey of a 140 × 80 pc2 region of 30 Doradus centered on R136, covering key optical diagnostic emission lines including Hα, Hβ, Hγ, [O III] λλ4363, 4959, 5007, [N II] λλ6548, 6584, [SII] λλ6717, 6731 [S III] λ6312, and in some locations [S III] λ9069. We present maps of fluxes and intensity ratios for these lines, and catalogs of isolated ionizing stars, elephant-trunk pillars, and edge-on ionization fronts. The final science-quality spectroscopic data products are available to the public. Our analysis of the new data finds that, while stellar …


Book Review: Stars Above, Earth Below: A Guide To Astronomy In The National Parks, T. D. Oswalt 2010 Florida Institute of Technology

Book Review: Stars Above, Earth Below: A Guide To Astronomy In The National Parks, T. D. Oswalt

Publications

This document is Dr. Oswalt’s review of Stars Above, Earth Below : a Guide to Astronomy in the National Parks by Tyler Nordgren. Springer/Praxis, 2010 444p, 9781441916488 $29.95.


3d Heliospheric Simulations Of Heavy Neutral Particles From The Interstellar Medium, Akito Kawamura 2010 University of Alabama in Huntsville

3d Heliospheric Simulations Of Heavy Neutral Particles From The Interstellar Medium, Akito Kawamura

Von Braun Symposium Student Posters

No abstract provided.


Candle In The Wind: Probing The Solar Wind Structure Using Interplanetary Scintillation Data, Tae K. Kim 2010 University of Alabama in Huntsville

Candle In The Wind: Probing The Solar Wind Structure Using Interplanetary Scintillation Data, Tae K. Kim

Von Braun Symposium Student Posters

No abstract provided.


Studying Gravitational Lensing Effect Using Grb From Fermi Mission, Roderick Davidson 2010 University of Alabama in Huntsville

Studying Gravitational Lensing Effect Using Grb From Fermi Mission, Roderick Davidson

Von Braun Symposium Student Posters

No abstract provided.


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