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2016

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Articles 31 - 60 of 401

Full-Text Articles in Astrophysics and Astronomy

Supplement: The Rate Of Binary Black Hole Mergers Inferred From Advanced Ligo Observations Surrounding Gw150914, B. P. Abbott, K. Gill, B. Hughey, M. J. Szczepańczyk, M. Zanolin, Et Al. Dec 2016

Supplement: The Rate Of Binary Black Hole Mergers Inferred From Advanced Ligo Observations Surrounding Gw150914, B. P. Abbott, K. Gill, B. Hughey, M. J. Szczepańczyk, M. Zanolin, Et Al.

Publications

This article provides supplemental information for a Letter reporting the rate of (BBH) coalescences inferred from 16 days of coincident Advanced LIGO observations surrounding the transient (GW) signal GW150914. In that work we reported various rate estimates whose 90% confidence intervals fell in the range 2–600 Gpc−3 yr−1. Here we give details on our method and computations, including information about our search pipelines, a derivation of our likelihood function for the analysis, a description of the astrophysical search trigger distribution expected from merging BBHs, details on our computational methods, a description of the effects and our model for calibration uncertainty, …

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Supplement: The Rate Of Binary Black Hole Mergers Inferred From Advanced Ligo Observations Surrounding Gw150914, B. P. Abbott, R. Abbott, T. D. Abbott, M. R. Abernathy, F. Acernese, K. Ackley, C. Adams, T. Adams, P. Addesso, R. X. Adhikari, V. B. Adya, C. Affeldt, M. Agathos, K. Agatsuma, N. Aggarwal, O. D. Aguiar, L. Aiello, A. Ain, P. Ajith, B. Allen, A. Allocca, P. A. Altin, S. B. Anderson, W. G. Anderson, K. Arai, M. C. Araya, C. C. Arceneaux, J. S. Areeda, N. Arnaud, K. G. Arun, S. Ascenzi, Tiffany Z. Summerscales Dec 2016

Supplement: The Rate Of Binary Black Hole Mergers Inferred From Advanced Ligo Observations Surrounding Gw150914, B. P. Abbott, R. Abbott, T. D. Abbott, M. R. Abernathy, F. Acernese, K. Ackley, C. Adams, T. Adams, P. Addesso, R. X. Adhikari, V. B. Adya, C. Affeldt, M. Agathos, K. Agatsuma, N. Aggarwal, O. D. Aguiar, L. Aiello, A. Ain, P. Ajith, B. Allen, A. Allocca, P. A. Altin, S. B. Anderson, W. G. Anderson, K. Arai, M. C. Araya, C. C. Arceneaux, J. S. Areeda, N. Arnaud, K. G. Arun, S. Ascenzi, Tiffany Z. Summerscales

Faculty Publications

© 2016. The American Astronomical Society. All rights reserved.. This article provides supplemental information for a Letter reporting the rate of (BBH) coalescences inferred from 16 days of coincident Advanced LIGO observations surrounding the transient (GW) signal GW150914. In that work we reported various rate estimates whose 90% confidence intervals fell in the range 2-600 Gpc-3yr-1. Here we give details on our method and computations, including information about our search pipelines, a derivation of our likelihood function for the analysis, a description of the astrophysical search trigger distribution expected from merging BBHs, details on our computational methods, a description of …

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Galaxy And Mass Assembly (Gama) : Detection Of Low-Surface-Brightness Galaxies From Sdss Data., Richard P. Williams, I. K. Baldry, L. S. Kelvin, P. A. James, S. P. Driver, M. Prescott, S. Brough, M. J. I. Brown, L. J. M. Davies, Benne W. Holwerda, J. Liske, P. Norberg, A. J. Moffett, A. H. Wright Dec 2016

Galaxy And Mass Assembly (Gama) : Detection Of Low-Surface-Brightness Galaxies From Sdss Data., Richard P. Williams, I. K. Baldry, L. S. Kelvin, P. A. James, S. P. Driver, M. Prescott, S. Brough, M. J. I. Brown, L. J. M. Davies, Benne W. Holwerda, J. Liske, P. Norberg, A. J. Moffett, A. H. Wright

Faculty and Staff Scholarship

We report on a search for new low-surface-brightness galaxies (LSBGs) using Sloan Digital Sky Survey (SDSS) data within the Galaxy And Mass Assembly (GAMA) equatorial fields. The search method consisted of masking objects detected with SDSS photo, combining gri images weighted to maximize the expected signal-to-noise ratio, and smoothing the images. The processed images were then run through a detection algorithm that finds all pixels above a set threshold and groups them based on their proximity to one another. The list of detections was cleaned of contaminants such as diffraction spikes and the faint wings of masked objects. From these, …

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Sdss-Iv Manga: A Serendipitous Observation Of A Potential Gas Accretion Event, Edmond Cheung, David V. Stark, Song Huang, Kate H. R. Rubin, Lihwai Lin, Christy Tremonti, Kai Zhang, Renbin Yan, Dmitry Bizyaev, Médéric Boquien Nov 2016

Sdss-Iv Manga: A Serendipitous Observation Of A Potential Gas Accretion Event, Edmond Cheung, David V. Stark, Song Huang, Kate H. R. Rubin, Lihwai Lin, Christy Tremonti, Kai Zhang, Renbin Yan, Dmitry Bizyaev, Médéric Boquien

Physics and Astronomy Faculty Publications

The nature of warm, ionized gas outside of galaxies may illuminate several key galaxy evolutionary processes. A serendipitous observation by the MaNGA survey has revealed a large, asymmetric Hα complex with no optical counterpart that extends ≈8'' (≈6.3 kpc) beyond the effective radius of a dusty, starbursting galaxy. This Hα extension is approximately three times the effective radius of the host galaxy and displays a tail-like morphology. We analyze its gas-phase metallicities, gaseous kinematics, and emission-line ratios and discuss whether this Hα extension could be diffuse ionized gas, a gas accretion event, or something else. We find …

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Direct Band Gap Measurements, John Ryan Peterson Nov 2016

Direct Band Gap Measurements, John Ryan Peterson

Student Works

This presentation was given during the summer of 2016 as part of the BYU REU program funded by the NSF. Here I give a brief explanation of our quantum dot synthesis and then explain the mechanism of photoluminsecence used to measure indirect band gap energies of semiconductors. Our experimental setup is shown. Direct band gaps of lead sulfide quantum dots synthesized in ferritin are reported. The data show that the band gap can be tuned arbitrarily in a certain range by varying the concentrations of the reactants. We compare stability of quantum dots in ferritin to quantum dots synthesized without …

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Quantum Dot Band Gap Measurements, John Ryan Peterson Nov 2016

Quantum Dot Band Gap Measurements, John Ryan Peterson

Student Works

This presentation was given during the summer of 2016 as part of the BYU REU program funded by the NSF. Here I give a brief explanation of our quantum dot synthesis as well as explain the use of absorption spectroscopy to measure indirect band gap energies of semiconductors. Our experimental setup is shown and recent improvements are explained. We report indirect band gaps of quantum dots containing varying amounts of cobalt oxide and manganese oxide and synthesized in the protein ferritin. The data show that the band gap can be tuned arbitrarily in a certain range by varying the concentrations …

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Determining The Index Of Refraction Of Aluminum Fluoride In The Ultra Violet Spectrum, Zoe Hughes Nov 2016

Determining The Index Of Refraction Of Aluminum Fluoride In The Ultra Violet Spectrum, Zoe Hughes

Student Works

A NASA project called Large UV/Optical/Infrared Surveyor (LUVOIR) is looking into ways to coat a mirror for a new space telescope. We contributed to this project by investigating aluminum fluoride (AlF3) as a possible coating for the mirror. We measured the index of refraction of AlF3 in the wavelength range 6 – 49.5 nm by testing three sample mirrors, each made up of a silicon wafer with a coating of AlF3. We took data at the Advanced Light Source (ALS) in Berkeley, California and in the laboratory at Brigham Young University (BYU). There are discrepancies …

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Sdss-Iv Manga Ifs Galaxy Survey—Survey Design, Execution, And Initial Data Quality, Renbin Yan, Kevin Bundy, David R. Law, Matthew A. Bershady, Brett Andrews, Brian Cherinka, Aleksandar M. Diamond-Stanic, Niv Drory, Nicholas Macdonald, José R. Sánchez-Gallego, Daniel Thomas, David A. Wake, Anne-Marie Weijmans, Kyle B. Westfall, Kai Zhang, Alfonso Aragón-Salamanca, Francesco Belfiore, Dmitry Bizyaev, Guillermo A. Blanc, Michael R. Blanton, Joel Brownstein, Michele Cappellari, Richard D'Souza, Eric Emsellem, Hai Fu, Patrick Gaulme, Mark T. Graham, Daniel Goddard, James E. Gunn, Paul Harding Nov 2016

Sdss-Iv Manga Ifs Galaxy Survey—Survey Design, Execution, And Initial Data Quality, Renbin Yan, Kevin Bundy, David R. Law, Matthew A. Bershady, Brett Andrews, Brian Cherinka, Aleksandar M. Diamond-Stanic, Niv Drory, Nicholas Macdonald, José R. Sánchez-Gallego, Daniel Thomas, David A. Wake, Anne-Marie Weijmans, Kyle B. Westfall, Kai Zhang, Alfonso Aragón-Salamanca, Francesco Belfiore, Dmitry Bizyaev, Guillermo A. Blanc, Michael R. Blanton, Joel Brownstein, Michele Cappellari, Richard D'Souza, Eric Emsellem, Hai Fu, Patrick Gaulme, Mark T. Graham, Daniel Goddard, James E. Gunn, Paul Harding

Physics and Astronomy Faculty Publications

The MaNGA Survey (Mapping Nearby Galaxies at Apache Point Observatory) is one of three core programs in the Sloan Digital Sky Survey IV. It is obtaining integral field spectroscopy for 10,000 nearby galaxies at a spectral resolution of R ~ 2000 from 3622 to 10354 Å. The design of the survey is driven by a set of science requirements on the precision of estimates of the following properties: star formation rate surface density, gas metallicity, stellar population age, metallicity, and abundance ratio, and their gradients; stellar and gas kinematics; and enclosed gravitational mass as a function of radius. We describe …

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Commercial Space Situational Awareness (Ssa) Capabilities And Their Benefits For Civilian Space Traffic Management (Stm), Mark A. Skinner Nov 2016

Commercial Space Situational Awareness (Ssa) Capabilities And Their Benefits For Civilian Space Traffic Management (Stm), Mark A. Skinner

Space Traffic Management Conference

Paralleling (but lagging) satellite development, SSA, long the sole domain of sophisticated militaries, now includes commercial providers. These commercial capabilities, identified as beneficial to the sustainable use of outer space[1], have demonstrated technical sophistication sufficient to positively contribute to the mitigation of satellite interference and provide actionable SSA information. Utilizing small optical telescopes, these entities are able to determine the orbits of objects in the geosynchronous orbit (GSO) to sizes as small as 1 m2, with measured positional uncertainties of 10s of meters, on the order of the size of a modern communications satellite. These techniques …

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Results Of The Deepest All-Sky Survey For Continuous Gravitational Waves On Ligo S6 Data Running On The Einstein@Home Volunteer Distributed Computing Project, B. P. Abbott, R. Abbott, T. D. Abbott, M. R. Abernathy, Teviet Creighton, Mario C. Diaz, Soma Mukherjee, Volker Quetschke, Malik Rakhmanov Nov 2016

Results Of The Deepest All-Sky Survey For Continuous Gravitational Waves On Ligo S6 Data Running On The Einstein@Home Volunteer Distributed Computing Project, B. P. Abbott, R. Abbott, T. D. Abbott, M. R. Abernathy, Teviet Creighton, Mario C. Diaz, Soma Mukherjee, Volker Quetschke, Malik Rakhmanov

Physics & Astronomy Faculty Publications

We report results of a deep all-sky search for periodic gravitational waves from isolated neutron stars in data from the S6 LIGO science run. The search was possible thanks to the computing power provided by the volunteers of the Einstein@Home distributed computing project. We find no significant signal candidate and set the most stringent upper limits to date on the amplitude of gravitational wave signals from the target population. At the frequency of best strain sensitivity, between 170.5 and 171 Hz we set a 90% confidence upper limit of 5.5×10-25, while at the high end of our frequency range, around …

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Results Of The Deepest All-Sky Survey For Continuous Gravitational Waves On Ligo S6 Data Running On The Einstein@Home Volunteer Distributed Computing Project, B. P. Abbott, K. Gill, B. Hughey, M. J. Szczepańczyk, Michele Zanolin, Et Al. Nov 2016

Results Of The Deepest All-Sky Survey For Continuous Gravitational Waves On Ligo S6 Data Running On The Einstein@Home Volunteer Distributed Computing Project, B. P. Abbott, K. Gill, B. Hughey, M. J. Szczepańczyk, Michele Zanolin, Et Al.

Publications

We report results of a deep all-sky search for periodic gravitational waves from isolated neutron stars in data from the S6 LIGO science run. The search was possible thanks to the computing power provided by the volunteers of the Einstein@Home distributed computing project.

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First Targeted Search For Gravitational-Wave Bursts From Core-Collapse Supernovae In Data Of First-Generation Laser Interferometer Detectors, B. P. Abbott, R. Abbott, T. D. Abbott, M. R. Abernathy, Hernan P. Daveloza, Mario C. Diaz, Joey S. Key, Soma Mukherjee, Volker Quetschke, Malik Rakhmanov, Joseph D. Romano Nov 2016

First Targeted Search For Gravitational-Wave Bursts From Core-Collapse Supernovae In Data Of First-Generation Laser Interferometer Detectors, B. P. Abbott, R. Abbott, T. D. Abbott, M. R. Abernathy, Hernan P. Daveloza, Mario C. Diaz, Joey S. Key, Soma Mukherjee, Volker Quetschke, Malik Rakhmanov, Joseph D. Romano

Physics & Astronomy Faculty Publications

We present results from a search for gravitational-wave bursts coincident with two core-collapse supernovae observed optically in 2007 and 2011. We employ data from the Laser Interferometer Gravitational-wave Observatory (LIGO), the Virgo gravitational-wave observatory, and the GEO 600 gravitational-wave observatory. The targeted core-collapse supernovae were selected on the basis of (1) proximity (within approximately 15 Mpc), (2) tightness of observational constraints on the time of core collapse that defines the gravitational-wave search window, and (3) coincident operation of at least two interferometers at the time of core collapse. We find no plausible gravitational-wave candidates. We present the probability of detecting …

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The Quenching Timescale And Quenching Rate Of Galaxies, Jianhui Lian, Renbin Yan, Kai Zhang, Xu Kong Nov 2016

The Quenching Timescale And Quenching Rate Of Galaxies, Jianhui Lian, Renbin Yan, Kai Zhang, Xu Kong

Physics and Astronomy Faculty Publications

The average star formation rate (SFR) in galaxies has been declining since the redshift of 2. A fraction of galaxies quench and become quiescent. We constrain two key properties of the quenching process: the quenching timescale and the quenching rate among galaxies. We achieve this by analyzing the galaxy number density profile in NUV−u color space and the distribution in NUV−u versus u − i color–color diagram with a simple toy-model framework. We focus on galaxies in three mass bins between 1010 and 1010.6 M ⊙. In the NUV−u versus u − i color–color …

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Mond Prediction For The Velocity Dispersion Of The "Feeble Giant" Crater Ii, Stacy S. Mcgaugh Nov 2016

Mond Prediction For The Velocity Dispersion Of The "Feeble Giant" Crater Ii, Stacy S. Mcgaugh

Faculty Scholarship

Crater II is an unusual object among the dwarf satellite galaxies of the Local Group in that it has a very large size for its small luminosity. This provides a strong test of MOND, as Crater II should be in the deep MOND regime (g in ≈ 34 km2 s-2 kpc-1 ≪ a 0 = 3700 km2 s-2 kpc-1). Despite its great distance (≈120 kpc) from the Milky Way, the external field of the host (g ex ≈ 282 km2 s-2 kpc-1) comfortably exceeds the internal field. Consequently, Crater II should be subject to the external field effect, a feature …

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An ‘Analytic Dynamical Magnetosphere’ Formalism For X-Ray And Optical Emission From Slowly Rotating Magnetic Massive Stars, S. P. Owocki, A. Ud-Doula, J. O. Sundqvist, V. Petit, David H. Cohen, R. H. D. Townsend Nov 2016

An ‘Analytic Dynamical Magnetosphere’ Formalism For X-Ray And Optical Emission From Slowly Rotating Magnetic Massive Stars, S. P. Owocki, A. Ud-Doula, J. O. Sundqvist, V. Petit, David H. Cohen, R. H. D. Townsend

Physics & Astronomy Faculty Works

Slowly rotating magnetic massive stars develop ‘dynamical magnetospheres’ (DMs), characterized by trapping of stellar wind outflow in closed magnetic loops, shock heating from collision of the upflow from opposite loop footpoints, and subsequent gravitational infall of radiatively cooled material. In 2D and 3D magnetohydrodynamic (MHD) simulations, the interplay among these three components is spatially complex and temporally variable, making it difficult to derive observational signatures and discern their overall scaling trends. Within a simplified, steady-state analysis based on overall conservation principles, we present here an ‘analytic dynamical magnetosphere’ (ADM) model that provides explicit formulae for density, temperature, and flow speed …

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Sparc: Mass Models For 175 Disk Galaxies With Spitzer Photometry And Accurate Rotation Curves, Federico Lelli, Stacy S. Mcgaugh Nov 2016

Sparc: Mass Models For 175 Disk Galaxies With Spitzer Photometry And Accurate Rotation Curves, Federico Lelli, Stacy S. Mcgaugh

Faculty Scholarship

We introduce SPARC (Spitzer Photometry and Accurate Rotation Curves): a sample of 175 nearby galaxies with new surface photometry at 3.6 μm and high-quality rotation curves from previous H I/Hα studies. SPARC spans a broad range of morphologies (S0 to Irr), luminosities (∼5 dex), and surface brightnesses (∼4 dex). We derive [3.6] surface photometry and study structural relations of stellar and gas disks. We find that both the stellar mass-H I mass relation and the stellar radius-H i radius relation have significant intrinsic scatter, while the H I mass-radius relation is extremely tight. We build detailed mass models and quantify …

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Tracing Slow Winds From T Tauri Stars Via Low-Velocity Forbidden Line Emission, M. N. Simon, I. Pascucci, Suzan Edwards, W. Feng, U. Gorti, D. Hollenbach, E. Rigliaco, J. T. Keane Nov 2016

Tracing Slow Winds From T Tauri Stars Via Low-Velocity Forbidden Line Emission, M. N. Simon, I. Pascucci, Suzan Edwards, W. Feng, U. Gorti, D. Hollenbach, E. Rigliaco, J. T. Keane

Astronomy: Faculty Publications

Using Keck/HIRES spectra (Δ v ∼ 7 km s−1) we analyze forbidden lines of [O I] 6300 Å, [O I] 5577 Å and [S II] 6731 Å from 33 T Tauri stars covering a range of disk evolutionary stages. After removing a high-velocity component (HVC) associated with microjets, we study the properties of the low-velocity component (LVC). The LVC can be attributed to slow disk winds that could be magnetically (magnetohydrodynamic) or thermally (photoevaporative) driven. Both of these winds play an important role in the evolution and dispersal of protoplanetary material. LVC emission is seen in all 30 stars with …

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Einstein@ Home Discovery Of A Double Neutron Star Binary In The Palfa Survey, P. Lazarus, P. C.C. Freire, B. Allen, C. Aulbert, O. Bock, S. Bogdanov, A. Brazier, F. Camilo, F. Cardoso, Fredrick Jenet Nov 2016

Einstein@ Home Discovery Of A Double Neutron Star Binary In The Palfa Survey, P. Lazarus, P. C.C. Freire, B. Allen, C. Aulbert, O. Bock, S. Bogdanov, A. Brazier, F. Camilo, F. Cardoso, Fredrick Jenet

Physics & Astronomy Faculty Publications

We use time-domain electromagnetic simulations to determine the spectral characteristics of the Hydrogen Epoch of Reionization Arrays (HERA) antenna. These simulations are part of a multi-faceted campaign to determine the effectiveness of the dish's design for obtaining a detection of redshifted 21 cm emission from the epoch of reionization. Our simulations show the existence of reflections between HERA's suspended feed and its parabolic dish reflector that fall below -40 dB at 150 ns and, for reasonable impedance matches, have a negligible impact on HERA's ability to constrain EoR parameters. It follows that despite the reflections they introduce, dishes are effective …

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Radial Acceleration Relation In Rotationally Supported Galaxies, Stacy S. Mcgaugh, Federico Lelli Nov 2016

Radial Acceleration Relation In Rotationally Supported Galaxies, Stacy S. Mcgaugh, Federico Lelli

Faculty Scholarship

We report a correlation between the radial acceleration traced by rotation curves and that predicted by the observed distribution of baryons. The same relation is followed by 2693 points in 153 galaxies with very different morphologies, masses, sizes, and gas fractions. The correlation persists even when dark matter dominates. Consequently, the dark matter contribution is fully specified by that of the baryons. The observed scatter is small and largely dominated by observational uncertainties. This radial acceleration relation is tantamount to a natural law for rotating galaxies.

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X-Ray Detected Active Galactic Nuclei In Dwarf Galaxies At 0 < Z < 1, K. Pardo, A. D. Goulding, J. E. Greene, R. S. Somerville, E. Gallo, R. C. Hickox Nov 2016

X-Ray Detected Active Galactic Nuclei In Dwarf Galaxies At 0 < Z < 1, K. Pardo, A. D. Goulding, J. E. Greene, R. S. Somerville, E. Gallo, R. C. Hickox

Dartmouth Scholarship

We present a sample of accreting supermassive black holes (SMBHs) in dwarf galaxies at z\lt 1. We identify dwarf galaxies in the NEWFIRM Medium Band Survey with stellar masses of {M}\star \lt 3× {10}9 {M}⊙ that have spectroscopic redshifts from the DEEP2 survey and lie within the region covered by deep (flux limit of ˜ 5× {10}-17{--}6× {10}-16 {erg} {{cm}}-2 {{{s}}}-1) archival Chandra X-ray data. From our sample of 605 dwarf galaxies, 10 exhibit X-ray emission consistent with that arising from active galactic nucleus (AGN) activity. If black-hole mass scales roughly …

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Probing Dark Matter-Neutrino Connection Via Indirect Detection Experiments, Bradley Knockel Nov 2016

Probing Dark Matter-Neutrino Connection Via Indirect Detection Experiments, Bradley Knockel

Physics & Astronomy ETDs

Various evidence reveals that dark matter is a primary component of this universe. The amount of dark matter is known, but its identity is a mystery. To determine its properties, efforts to detect and produce dark matter are underway. Dark matter annihilations throughout the galaxy may produce photons, neutrinos, and cosmic rays. Neutrino and photon detectors may then indirectly detect dark matter by detecting these annihilation products. The annihilation rate, dark matter mass, and dark matter scattering rate off of matter affect the signals received at Earth. These signals can therefore probe the identity of dark matter, especially if dark …

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An Analysis Of Archival Observations Made Of Galactic Supernova Remnants By The Chandra X-Ray Observatory, Daniel M. Rush, Haley E. West Nov 2016

An Analysis Of Archival Observations Made Of Galactic Supernova Remnants By The Chandra X-Ray Observatory, Daniel M. Rush, Haley E. West

Posters-at-the-Capitol

Since its launch in 1999, the Chandra X-ray Observatory has spurred explosive growth in the study of Galactic supernova remnants (SNRs) due to its unsurpassed angular resolution (1 arcsecond at 1 keV) and its moderate sensitivity. We are currently analyzing archival observations made by Chandra of two particular classes of SNRs: mixed-morphology SNRs (which feature contrasting center-filled thermal X-ray morphologies with shell-like radio morphologies) and synchrotron X-ray SNRs (which feature X-ray spectra dominated by synchrotron emission). To illustrate some of our initial results, we present spatially resolved spectroscopic analyses of the mixed-morphology SNR 3C 397 and the synchrotron X-ray dominated …

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A Search For Very High-Energy Gamma Rays From The Missing Link Binary Pulsar J1023+0038 With Veritas, P. T. Reynolds, Et Al Nov 2016

A Search For Very High-Energy Gamma Rays From The Missing Link Binary Pulsar J1023+0038 With Veritas, P. T. Reynolds, Et Al

Physical Sciences Publications

The binary millisecond radio pulsar PSR J1023+0038 exhibits many characteristics similar to the gamma-ray binary system PSR B1259–63/LS 2883, making it an ideal candidate for the study of high-energy nonthermal emission. It has been the subject of multiwavelength campaigns following the disappearance of the pulsed radio emission in 2013 June, which revealed the appearance of an accretion disk around the neutron star. We present the results of very high energy (VHE) gamma-ray observations carried out by the Very Energetic Radiation Imaging Telescope Array System before and after this change of state. Searches for steady and pulsed emission of both data …

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Holographic Renormalization Of Einstein-Maxwell-Dilaton Theories, Bom Soo Kim Nov 2016

Holographic Renormalization Of Einstein-Maxwell-Dilaton Theories, Bom Soo Kim

Physics and Astronomy Faculty Publications

We generalize the boundary value problem with a mixed boundary condition that involves the gauge and scalar fields in the context of Einstein-Maxwell-Dilaton theories. In particular, the expectation value of the dual scalar operator can be a function of the expectation value of the current operator. The properties are prevalent in a fixed charge ensemble because the conserved charge is shared by both fields through the dilaton coupling, which is also responsible for non-Fermi liquid properties. We study the on-shell action and the stress energy tensor to note practical importances of the boundary value problem. In the presence of the …

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High Power Optically Pumped Semiconductor Lasers For Sodium Guidestar Applications, Shawn W. Hackett Nov 2016

High Power Optically Pumped Semiconductor Lasers For Sodium Guidestar Applications, Shawn W. Hackett

Optical Science and Engineering ETDs

Optically pumped semiconductor lasers (OPSLs) are shown to provide a much more compact and less expensive source for illumination of the sodium layer of the mesosphere for use as a sodium laser guidestar via single and two photon excitation schemes. This represents a revolution in laser guidestar technology as the cost, size, and power requirements for a laser guidestar system are shown to have been decreased by an order of magnitude with guidestar performance shown to be similar to previous sources. Sodium laser guidestar sources for broadband simultaneous illumination of multiple lines are developed and simulated. Simulations are then compared …

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Hd 164492c: A Rapidly Rotating, Hα-Bright, Magnetic Early B Star Associated With A 12.5 D Spectroscopic Binary, G. A. Wade, M. Shultz, J. Sikora, M.-E. Bernier, Th. Rivinius, E. Alecian, V. Petit, J. H. Grunhut, Binamics Collaboration Nov 2016

Hd 164492c: A Rapidly Rotating, Hα-Bright, Magnetic Early B Star Associated With A 12.5 D Spectroscopic Binary, G. A. Wade, M. Shultz, J. Sikora, M.-E. Bernier, Th. Rivinius, E. Alecian, V. Petit, J. H. Grunhut, Binamics Collaboration

Aerospace, Physics, and Space Science Faculty Publications

We employ high-resolution spectroscopy and spectropolarimetry to derive the physical proper- ties and magnetic characteristics of the multiple system HD 164492C, located in the young open cluster M20. The spectrum reveals evidence of three components: a broad-lined early B star (HD 164492C1), a narrow-lined early B star (HD 164492C2) and a late B star (HD 164492C3). Components C2 and C3 exhibit significant (>100 km s−1) bulk radial velocity variations with a period of 12.5351(7) d that we attribute to eccentric binary motion around a common centre- of-mass. Component C1 exhibits no detectable radial velocity variations. Using constraints derived from …

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A Discrete Chemo-Dynamical Model Of The Giant Elliptical Galaxy Ngc 5846: Dark Matter Fraction, Internal Rotation, And Velocity Anisotropy Out To Six Effective Radii, Ling Zhu, Aaron Romanowsky, Glenn Van De Ven, R. Long, Laura Watkins, Vincenzo Pota, Nicola Napolitano, Duncan Forbes, Jean Brodie, Caroline Foster Nov 2016

A Discrete Chemo-Dynamical Model Of The Giant Elliptical Galaxy Ngc 5846: Dark Matter Fraction, Internal Rotation, And Velocity Anisotropy Out To Six Effective Radii, Ling Zhu, Aaron Romanowsky, Glenn Van De Ven, R. Long, Laura Watkins, Vincenzo Pota, Nicola Napolitano, Duncan Forbes, Jean Brodie, Caroline Foster

Faculty Publications

We construct a suite of discrete chemo-dynamical models of the giant elliptical galaxy NGC 5846. These models are a powerful tool to constrain both the mass distribution and internal dynamics of multiple tracer populations. We use Jeans models to simultaneously fit stellar kinematics within the effective radius Re, planetary nebula (PN) radial velocities out to 3 Re, and globular cluster (GC) radial velocities and colours out to 6 Re. The best-fitting model is a cored dark matter halo which contributes ∼10 per cent of the total mass within 1 Re, and 67 per cent ± 10 per cent within 6 …

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Orbital Solutions And Absolute Elements Of The Massive Algol Binary Et Tauri, Richard M. Williamon, Horace Dale, Charles L. Evavold, Alexander Langoussis, Francis C. Fekel, Matthew W. Muterspaugh, Stephen Williams, Kate Napier, James R. Sowell Nov 2016

Orbital Solutions And Absolute Elements Of The Massive Algol Binary Et Tauri, Richard M. Williamon, Horace Dale, Charles L. Evavold, Alexander Langoussis, Francis C. Fekel, Matthew W. Muterspaugh, Stephen Williams, Kate Napier, James R. Sowell

Information Systems and Engineering Management Research Publications

We acquired differential UBV photoelectric photometry and radial velocities of the relatively bright, understudied, massive Algol binary ET Tau and utilized the Wilson-Devinney (WD) analysis program to obtain a simultaneous solution of these observations. To improve the orbital ephemeris, the V measurements from the ASAS program were also analyzed. Because of the very rapid rotation of the significantly more massive and hotter component (B2/3 spectral class), only radial velocities of the secondary component, which has a ∼B7 spectral class, could be measured. We derive masses of ${M}_{1}=14.34\pm 0.28\,{M}_{\odot }$ and ${M}_{2}=6.339\pm 0.117\,{M}_{\odot }$ and equal-volume radii of ${R}_{1}=6.356\pm 0.056\,{R}_{\odot }$ …

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Kelt-17b: A Hot-Jupiter Transiting An A-Star In A Misaligned Orbit Detected With Doppler Tomography, G. Zhou, J. E. Rodriguez, K. A. Collins, T. Beatty, T. Oberst, T. M. Heintz, K. G. Stassun, D. W. Latham, R. B. Kuhn, A. Bieryla, M. B. Lund, J. Labadie-Bartz, R. J. Siverd, D. J. Stevens, B. S. Gaudi, J. Pepper, L. A. Buchhave, J. Eastman, K. Colón, P. Cargile, D. James, J. Gregorio, P. A. Reed, Eric L.N. Jensen, David H. Cohen, K. K. Mcleod, T. G. Tan, R. Zambelli, D. Bayliss, J. Bento, G. A. Esquerdo, P. Berlind, M. L. Calkins, K. Blancato, M. Manner, C. Samulski, C. Stockdale, P. Nelson, D. Stephens, I. Curtis, J. Kielkopf, B. J. Fulton, D. L. Depoy, J. L. Marshall, R. Pogge, A. Gould, M. Trueblood, P. Trueblood Nov 2016

Kelt-17b: A Hot-Jupiter Transiting An A-Star In A Misaligned Orbit Detected With Doppler Tomography, G. Zhou, J. E. Rodriguez, K. A. Collins, T. Beatty, T. Oberst, T. M. Heintz, K. G. Stassun, D. W. Latham, R. B. Kuhn, A. Bieryla, M. B. Lund, J. Labadie-Bartz, R. J. Siverd, D. J. Stevens, B. S. Gaudi, J. Pepper, L. A. Buchhave, J. Eastman, K. Colón, P. Cargile, D. James, J. Gregorio, P. A. Reed, Eric L.N. Jensen, David H. Cohen, K. K. Mcleod, T. G. Tan, R. Zambelli, D. Bayliss, J. Bento, G. A. Esquerdo, P. Berlind, M. L. Calkins, K. Blancato, M. Manner, C. Samulski, C. Stockdale, P. Nelson, D. Stephens, I. Curtis, J. Kielkopf, B. J. Fulton, D. L. Depoy, J. L. Marshall, R. Pogge, A. Gould, M. Trueblood, P. Trueblood

Physics & Astronomy Faculty Works

We present the discovery of a hot Jupiter transiting the V = 9.23 mag main-sequence A-star KELT-17 (BD+14 1881). KELT-17b is a ${1.31}_{-0.29}^{+0.28}\,{M}_{{\rm{J}}}$, ${1.525}_{-0.060}^{+0.065}\,{R}_{{\rm{J}}}$ hot-Jupiter in a 3.08-day period orbit misaligned at −115fdg9 ± 4fdg1 to the rotation axis of the star. The planet is confirmed via both the detection of the radial velocity orbit, and the Doppler tomographic detection of the shadow of the planet during two transits. The nature of the spin–orbit misaligned transit geometry allows us to place a constraint on the level of differential rotation in the host star; we find that KELT-17 is consistent with …

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The Mid-Infrared Luminosity Evolution And Luminosity Function Of Quasars With Wise And Sdss, Jack Singal Nov 2016

The Mid-Infrared Luminosity Evolution And Luminosity Function Of Quasars With Wise And Sdss, Jack Singal

Physics Faculty Publications

We determine the 22 μm luminosity evolution and luminosity function for quasars from a data set of over 20,000 objects obtained by combining flux-limited Sloan Digital Sky Survey optical and Wide field Infrared Survey Explorer mid-infrared data. We apply methods developed in previous works to access the intrinsic population distributions non-parametrically, taking into account the truncations and correlations inherent in the data. We find that the population of quasars exhibits positive luminosity evolution with redshift in the mid-infrared, but with considerably less mid-infrared evolution than in the optical or radio bands. With the luminosity evolutions accounted for, we determine …

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