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Advanced Ligo, Tiffany Summerscales, LIGO Scientific Collaboration 2015 Andrews University

Advanced Ligo, Tiffany Summerscales, Ligo Scientific Collaboration

Faculty Publications

No abstract provided.


Characterization Of The Ligo Detectors During Their Sixth Science Run, Tiffany Summerscales, LIGO Collaboration 2015 Andrews University

Characterization Of The Ligo Detectors During Their Sixth Science Run, Tiffany Summerscales, Ligo Collaboration

Faculty Publications

In 2009–2010, the Laser Interferometer Gravitational-Wave Observatory (LIGO) operated together with international partners Virgo and GEO600 as a network to search for gravitational waves (GWs) of astrophysical origin. The sensitivity of these detectors was limited by a combination of noise sources inherent to the instrumental design and its environment, often localized in time or frequency, that couple into the GW readout. Here we review the performance of the LIGO instruments during this epoch, the work done to characterize the detectors and their data, and the effect that transient and continuous noise artefacts have on the sensitivity of LIGO to a …


Taurus, Luis M. Torres Cantu 2015 Parkland College

Taurus, Luis M. Torres Cantu

Natural Sciences Student Research Presentations

The purpose of this project was to gather information about the stars and objects in the constellation Taurus. This is a project for the Natural Sciences Poster Session at Parkland College.


Cygnus The Swan, Emily J. Oldham 2015 Parkland College

Cygnus The Swan, Emily J. Oldham

Natural Sciences Student Research Presentations

The purpose of this project was to gather information about the stars and objects in the constellation Cygnus. This is a project for the Natural Sciences Poster Session at Parkland College.


Evidence Of Attenuation Of Vhe Blazar Spectra By Extragalactic Background Light, Cameron Allen 2015 California Polytechnic State University - San Luis Obispo

Evidence Of Attenuation Of Vhe Blazar Spectra By Extragalactic Background Light, Cameron Allen

Physics

The spectrum of two blazar objects, 1ES 1959+650 and 1ES 2344+514, are analyzed for evidence of interactions with the Extragalactic Background Light (EBL), using combined data from the Very Energetic Radiation Imaging Telescope Array System and the Fermi Gamma-ray Space Telescope, By analyzing the distinct curvature across the combined spectrum, we infer that the very-high energy (VHE) gamma-rays must be attenuated by interactions with the EBL. We also find that the measured 1ES 1959+650 spectrum is sensitive to the intrinsic blazar model, with a preference for a power-law with an exponential cutoff (EPWL). The measured curvature is a combination of …


Lattice Study Of Quark And Glue Momenta And Angular Momenta In The Nucleon, M. Deka, T. Doi, Y. B. Yang, B. Chakraborty, S. J. Dong, Terrence Draper, M. Glatzmaier, M. Gong, H. W. Lin, Keh-Fei Liu, D. Mankame, N. Mathur, T. Streuer 2015 Bogoliubov Laboratory of Theoretical Physics, Russia

Lattice Study Of Quark And Glue Momenta And Angular Momenta In The Nucleon, M. Deka, T. Doi, Y. B. Yang, B. Chakraborty, S. J. Dong, Terrence Draper, M. Glatzmaier, M. Gong, H. W. Lin, Keh-Fei Liu, D. Mankame, N. Mathur, T. Streuer

Physics and Astronomy Faculty Publications

We report a complete calculation of the quark and glue momenta and angular momenta in the proton. These include the quark contributions from both the connected and disconnected insertions. The quark disconnected insertion loops are computed with Z4 noise, and the signal-to-noise ratio is improved with unbiased subtractions. The glue operator is comprised of gauge-field tensors constructed from the overlap operator. The calculation is carried out on a 163×24 quenched lattice at β=6.0 for Wilson fermions with κ=0.154, 0.155, and 0.1555, which correspond to pion masses at 650, 538, and 478 MeV, respectively. The chirally …


Kibble-Zurek Scaling In Holographic Quantum Quench: Backreaction, Sumit R. Das, Takeshi Morita 2015 University of Kentucky

Kibble-Zurek Scaling In Holographic Quantum Quench: Backreaction, Sumit R. Das, Takeshi Morita

Physics and Astronomy Faculty Publications

We study gauge and gravity backreaction in a holographic model of quantum quench across a superfluid critical transition. The model involves a complex scalar field coupled to a gauge and gravity field in the bulk. In earlier work (arXiv:1211.7076) the scalar field had a strong self-coupling, in which case the backreaction on both the metric and the gauge field can be ignored. In this approximation, it was shown that when a time dependent source for the order parameter drives the system across the critical point at a rate slow compared to the initial gap, the dynamics in the critical region …


Astronomy 102 Stars, Galaxies, The Universe Fall 2015, Erik Johnson 2015 Parkland College

Astronomy 102 Stars, Galaxies, The Universe Fall 2015, Erik Johnson

Astronomy Courses

No abstract provided.


Astronomy 102 Stars, Galaxies, The Universe Spring 2015, Erik Johnson 2015 Parkland College

Astronomy 102 Stars, Galaxies, The Universe Spring 2015, Erik Johnson

Astronomy Courses

No abstract provided.


Astronomy 101 Online The Solar System Summer 2015, Pam Friese, Katrina Wefel 2015 Parkland College

Astronomy 101 Online The Solar System Summer 2015, Pam Friese, Katrina Wefel

Astronomy Courses

No abstract provided.


On X-Ray Pulsations In Beta Cephei-Type Variables, L. Oskinova, H. Todt, D. Huenemoerder, S. Hubrig, Richard Ignace, W.-R. Hamann, L. Balona 2015 University of Potsdam

On X-Ray Pulsations In Beta Cephei-Type Variables, L. Oskinova, H. Todt, D. Huenemoerder, S. Hubrig, Richard Ignace, W.-R. Hamann, L. Balona

ETSU Faculty Works

Beta Cephei-type variables are early B-type stars that are characterized by oscillations observable in their optical light curves. At least one Beta Cep-variable also shows periodic variability in X-rays. Here we study the X-ray light curves in a sample of beta Cep-variables to investigate how common X-ray pulsations are for this type of stars. We searched the Chandra and XMM-Newton X-ray archives and selected stars that were observed by these telescopes for at least three optical pulsational periods. We retrieved and analyzed the X-ray data for kappa Sco, beta Cru, and alpha Vir. The X-ray light curves of these objects …


Interdisciplinary Connections Between Science & Theatre, Jessica N. Dotson 2015 Virginia Commonwealth University

Interdisciplinary Connections Between Science & Theatre, Jessica N. Dotson

Theses and Dissertations

Abstract

INTERDISCIPLINARY CONNECTIONS BETWEEN SCIENCE & THEATRE

Jessica Nicole Dotson

A thesis submitted in partial fulfillment of the requirements for the degree of Master of Fine Arts at Virginia Commonwealth University.

Virginia Commonwealth University, 2015.

Major Director: Dr. Noreen C. Barnes, Director of Graduate Studies, Associate Professor of Theatre

In the 1990s, astronomer Peter Usher was searching for new ways to teach his introductory astronomy class at Pennsylvania State University. He began to engage his students by searching for astronomical connections from other disciplines. His focus was turned to the arts, especially the works of William Shakespeare. Usher found, while …


An Economic Analysis Of Mars Exploration And Colonization, Clayton Knappenberger 15 2015 DePauw University

An Economic Analysis Of Mars Exploration And Colonization, Clayton Knappenberger 15

Honor Scholar Theses

No abstract provided.


Spectral Study Of Asteroids And Laboratory Simulation Of Asteroid Organics, Kelsey Hargrove 2015 University of Central Florida

Spectral Study Of Asteroids And Laboratory Simulation Of Asteroid Organics, Kelsey Hargrove

Electronic Theses and Dissertations

We investigate the spectra of asteroids at near- and mid-infrared wavelengths. In 2010 and 2011 we reported the detection of 3 ?m and 3.2-3.6 ?m signatures on (24) Themis and (65) Cybele indicative of water-ice and complex organics [1] [2] [3]. We further probed other primitive asteroids in the Cybele dynamical group and Themis family, finding diversity in the shape of their 3 ?m [4] [5] [6] and 10 ?m spectral features [4]. These differences indicated mineralogical and compositional variations within these asteroid populations. Also in the mid-infrared region we studied a larger population of asteroids belonging to the Bus …


A Method For Determining The Mass Composition Of Ultra-High Energy Cosmic Rays By Predicting The Depth Of First Interaction Of Individual Extensive Air Showers, Tolga Yapici 2015 Michigan Technological University

A Method For Determining The Mass Composition Of Ultra-High Energy Cosmic Rays By Predicting The Depth Of First Interaction Of Individual Extensive Air Showers, Tolga Yapici

Dissertations, Master's Theses and Master's Reports - Open

Particle accelerators have been used to characterize the properties of particle and subatomic particles. The most advanced particle accelerators built, LHC, can run at 1017 eV. It is not possible with current technology to accelerate particle to the energies that can be detected by cosmic ray observatories.

In the past, by the direct measurements of cosmic rays, scientists discovered sub-atomic particles. Being accelerated to energies higher than 1018 eV, cosmic rays carry important information for particle physics. We have developed a method, which is a combination of Artificial Neural Networks and simple algebraic method that uses parameters from the extensive …


Spectroscopic Confirmation Of The Existence Of Large, Diffuse Galaxies In The Coma Cluster, Pieter van Dokkum, Aaron Romanowsky, Roberto Abraham, Jean Brodie, Charlie Conroy, Marla Geha, Allison Merritt, Alexa Villaume, Jielai Zhang 2015 Yale University

Spectroscopic Confirmation Of The Existence Of Large, Diffuse Galaxies In The Coma Cluster, Pieter Van Dokkum, Aaron Romanowsky, Roberto Abraham, Jean Brodie, Charlie Conroy, Marla Geha, Allison Merritt, Alexa Villaume, Jielai Zhang

Faculty Publications

No abstract provided.


Spectral Results For The Blue Plume Stars In Canis Major Overdensity, Mirza Sharoz Rafiul Islam 2015 University of Kentucky

Spectral Results For The Blue Plume Stars In Canis Major Overdensity, Mirza Sharoz Rafiul Islam

Theses and Dissertations--Physics and Astronomy

We present distances and kinematics and look at the possible populations for the blue plume (BP) stars in the Canis Major Overdensity (CMa). We conducted a medium resolution spectral survey on the BP stars (N=303) in CMa (centered at l = 238° ; b = -8°) using the data from AAOmega Spectrograph. We used a modified version of the Statistics-sensitive Non-linear Iterative Peak-clipping (SNIP) algorithm to normalize our fluxed absorption spectra. After determining the radial velocities from measurements of strong absorption features for the stars we use a Bayesian analysis of spectral feature strengths and photometric colors to determine Teff, …


Characterizing The Nearest Young Moving Groups, Kyle McCarthy 2015 University of Kentucky

Characterizing The Nearest Young Moving Groups, Kyle Mccarthy

Theses and Dissertations--Physics and Astronomy

Moving groups are associations of stars which originated from the same star forming region. These groups are typically young (< 200 Myr) since they have not dissipated into the galactic field population. Over the last 15 years, roughly 10 such moving groups have been found with distances < 150 pc (7 with distances < 100 pc), each with a unique velocity and position.

This work first investigates the likelihood to resolve star from two moving groups (AB Doradus and Beta Pictoris) using high spacial resolution optical interferrometry and found 5 AB Doradus stars and 1 Beta Pictoris star with declinations > -30 could be spacially resolved.

To more deeply characterize individual groups, we used the 2.7m telescope at the McDonald Observatory to observe 10 proposed AB Doradus stars and 5 proposed Octans-Near stars (3 probable members, 2 possible) with high resolution (R ~60,000) optical …


Quantum Tests Of The Einstein Equivalence Principle With The Ste-Quest Space Mission, Brett Altschul, Quentin G. Bailey, Luc Blanchet, Kai Bongs, Philippe Bouyer, Luigi Cacciapuoti, et al. 2015 University of South Carolina

Quantum Tests Of The Einstein Equivalence Principle With The Ste-Quest Space Mission, Brett Altschul, Quentin G. Bailey, Luc Blanchet, Kai Bongs, Philippe Bouyer, Luigi Cacciapuoti, Et Al.

Publications

We present in detail the scientific objectives in fundamental physics of the Space–Time Explorer and QUantum Equivalence Space Test (STE–QUEST) space mission. STE–QUEST was pre-selected by the European Space Agency together with four other missions for the cosmic vision M3 launch opportunity planned around 2024. It carries out tests of different aspects of the Einstein Equivalence Principle using atomic clocks, matter wave interferometry and long distance time/frequency links, providing fascinating science at the interface between quantum mechanics and gravitation that cannot be achieved, at that level of precision, in ground experiments. We especially emphasize the specific strong interest of performing …


Feldspathic Rocks On Mars: Compositional Constraints From Infrared Spectroscopy And Possible Formation Mechanisms, Deanne Rogers, Hanna Nekvasil 2015 SUNY Stony Brook

Feldspathic Rocks On Mars: Compositional Constraints From Infrared Spectroscopy And Possible Formation Mechanisms, Deanne Rogers, Hanna Nekvasil

Department of Geosciences Faculty Publications

Rare feldspar-dominated surfaces on Mars were previously reported based on near-infrared (NIR) spectral data and were interpreted to consist of anorthosite or felsic rocks. Using thermal infrared (TIR) data over the feldspar detections with the largest areal extent in Nili Patera and Noachis Terra, we rule out felsic interpretations. Basaltic or anorthositic compositions are consistent with TIR measurements, but the geologic contexts for these regions do not support a plutonic origin. Laboratory NIR spectral measurements demonstrate that large plagioclase crystals (>~840 μm) can be detected in mixtures with as much as 50 vol % mafics, which is higher than …


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