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2015

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Articles 391 - 420 of 460

Full-Text Articles in Astrophysics and Astronomy

Lambda Lambda Correlation Function In Au + Au Collisions At Sqrt(S_Nn) = 200 Gev, Adam Gibson-Even, Shirvel Stanislaus, Donald Koetke, Star Collaboration Jan 2015

Lambda Lambda Correlation Function In Au + Au Collisions At Sqrt(S_Nn) = 200 Gev, Adam Gibson-Even, Shirvel Stanislaus, Donald Koetke, Star Collaboration

Physics and Astronomy Faculty Publications

No abstract provided.

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Identification Of High Energy Cosmic Ray Electrons Using Advanced Techniques In Calet And Fermi Lat, Aaron James Worley Jan 2015

Identification Of High Energy Cosmic Ray Electrons Using Advanced Techniques In Calet And Fermi Lat, Aaron James Worley

Electronic Theses and Dissertations

Measurements of the cosmic ray electron spectrum have received much attention over the last decade as anomalies in both electron and positron observations have been detected independently by several experiments. The profound possible implications in the fields of high energy astrophysics and particle physics have allowed for many interpretations on the origin of these inconsistencies in the spectra. This research focuses on two space-borne cosmic radiation experiments at different stages in their mission lifetimes: the Calorimetric Electron Telescope (CALET) and the Fermi Large Area Telescope (LAT). We explore the proton-electron discriminating capabilities of the CALET instrument through Monte Carlo simulations. …

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Binary Star Systems With Asymmetrically Heated Disks: Thermal Phase Curves For The Disk In Epsilon Aurigae, Richard Luther Pearson Iii Jan 2015

Binary Star Systems With Asymmetrically Heated Disks: Thermal Phase Curves For The Disk In Epsilon Aurigae, Richard Luther Pearson Iii

Electronic Theses and Dissertations

Epsilon Aurigae is a long-period eclipsing binary that contains a warm F-star (~7750 K) and a circumstellar disk enshrouding a hidden companion, likely to be a hot B-star (>15,000 K). The eclipse itself lasts just over two years---thanks, in part, to the size of the disk---and occurs every 27.1-years. Its evolutionary status is still debated, along with the true nature of each stellar component, due to the high uncertainty in its parallax. The disk is similarly debated from the near absence of solid state infrared spectral features indicating its composition, particle size distribution, and density. An investigation of a …

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Small Scatter And Nearly Isothermal Mass Profiles To Four Half-Light Radii From Two-Dimensional Stellar Dynamics Of Early-Type Galaxies, Michele Cappellari, Aaron Romanowsky, Jean Brodie, Duncan Forbes, Jay Strader, Caroline Foster, Sreeja Kartha, Nicola Pastorello, Vincenzo Pota, Lee Spitler, Christopher Usher, Jacob Arnold Jan 2015

Small Scatter And Nearly Isothermal Mass Profiles To Four Half-Light Radii From Two-Dimensional Stellar Dynamics Of Early-Type Galaxies, Michele Cappellari, Aaron Romanowsky, Jean Brodie, Duncan Forbes, Jay Strader, Caroline Foster, Sreeja Kartha, Nicola Pastorello, Vincenzo Pota, Lee Spitler, Christopher Usher, Jacob Arnold

Faculty Publications

No abstract provided.

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Hiding In Plain Sight: Record-Breaking Compact Stellar Systems In The Sloan Digital Sky Survey, Michael Sandoval, Richard Vo, Aaron Romanowsky, Jay Strader, Jieun Choi, Zachary Jennings, Charlie Conroy, Jean Brodie, Caroline Foster, Alexa Villaume, Mark Norris, Joachim Janz, Duncan Forbes Jan 2015

Hiding In Plain Sight: Record-Breaking Compact Stellar Systems In The Sloan Digital Sky Survey, Michael Sandoval, Richard Vo, Aaron Romanowsky, Jay Strader, Jieun Choi, Zachary Jennings, Charlie Conroy, Jean Brodie, Caroline Foster, Alexa Villaume, Mark Norris, Joachim Janz, Duncan Forbes

Faculty Publications

No abstract provided.

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Observations, Thermochemical Calculations, And Modeling Of Exoplanetary Atmospheres, Jasmina Blecic Jan 2015

Observations, Thermochemical Calculations, And Modeling Of Exoplanetary Atmospheres, Jasmina Blecic

Electronic Theses and Dissertations

This dissertation as a whole aims to provide the means to better understand hot-Jupiter planets through observing, performing thermochemical calculations, and modeling their atmospheres. We used Spitzer multi-wavelength secondary-eclipse observations to characterize planetary atmospheres. We chose targets with high signal-to-noise ratios, as their deep eclipses allow us to detect signatures of spectral features and assess planetary atmospheric structure and composition with greater certainty. Chapter 1 gives a short introduction. Chapter 2 presents the Spitzer secondary-eclipse analysis and atmospheric characterization of WASP-14b. The decrease in flux when a planet passes behind its host star reveals the planet dayside thermal emission, which, …

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The Percy Roope Papers, Percy M. Roope Jan 2015

The Percy Roope Papers, Percy M. Roope

Finding Aids

Percy M. Roope was a Professor of Physics at Clark University from 1921 to 1967. He was a student of Robert H. Goddard and was present at Goddard's first successful launch in 1926. His papers consist of interviews with him concerning Dr. Goddard and correspondence with him.

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Astronomy 101-201h The Solar System Fall 2015, Katrina Wefel Jan 2015

Astronomy 101-201h The Solar System Fall 2015, Katrina Wefel

Astronomy Courses

No abstract provided.

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Astronomy 101 The Solar System Fall 2015, Erik Johnson Jan 2015

Astronomy 101 The Solar System Fall 2015, Erik Johnson

Astronomy Courses

No abstract provided.

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Astronomy 101-002 The Solar System Fall 2015, David Leake Jan 2015

Astronomy 101-002 The Solar System Fall 2015, David Leake

Astronomy Courses

No abstract provided.

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Astronomy 101-051w The Solar System Fall 2015, Pam Friese Jan 2015

Astronomy 101-051w The Solar System Fall 2015, Pam Friese

Astronomy Courses

No abstract provided.

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Astronomy 101-001 The Solar System Fall 2015, Katrina Wefel Jan 2015

Astronomy 101-001 The Solar System Fall 2015, Katrina Wefel

Astronomy Courses

No abstract provided.

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Astronomy 101-003 The Solar System Spring 2015, Erik Johnson Jan 2015

Astronomy 101-003 The Solar System Spring 2015, Erik Johnson

Astronomy Courses

No abstract provided.

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Astronomy 101-002 The Solar System Spring 2015, David Leake Jan 2015

Astronomy 101-002 The Solar System Spring 2015, David Leake

Astronomy Courses

No abstract provided.

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Astronomy 101-001 The Solar System Spring 2015, Katrina Wefel Jan 2015

Astronomy 101-001 The Solar System Spring 2015, Katrina Wefel

Astronomy Courses

No abstract provided.

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

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

Astronomy Courses

No abstract provided.

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Astronomy 101-051w The Solar System Spring 2015, Pam Friese Jan 2015

Astronomy 101-051w The Solar System Spring 2015, Pam Friese

Astronomy Courses

No abstract provided.

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Astronomy 101 Online The Solar System Summer 2015, Pam Friese Jan 2015

Astronomy 101 Online The Solar System Summer 2015, Pam Friese

Astronomy Courses

No abstract provided.

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Orion, Teresa M. Boerma Jan 2015

Orion, Teresa M. Boerma

Natural Sciences Student Research Presentations

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

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Dye Distance Mapping Using Waveguide Evanescent Field Fluorescence Microscopy And Its Application To Cell Biology, Frederik Fleissner, Michael Morawitz, S. Jeffrey Dixon, Uwe Langbein, Silvia Mittler Jan 2015

Dye Distance Mapping Using Waveguide Evanescent Field Fluorescence Microscopy And Its Application To Cell Biology, Frederik Fleissner, Michael Morawitz, S. Jeffrey Dixon, Uwe Langbein, Silvia Mittler

Physics and Astronomy Publications

Previous studies have measured the distance between cells and the substratum at sites of adhesion via the emission of a fluorescent dye and waveguide methods. Here, we demonstrate a novel approach to measure the position of fluorescent dyes above a waveguide surface in the 10-200 nm distance range throughout an entire area, yielding a 2D dye distance map or a 3D contour plot. The dye is located in a multilayered Langmuir Blodgett (LB) film or in the plasma membrane of a cell. Waveguide evanescent field fluorescence (WEFF) images obtained using two different waveguide modes are employed allowing, with a simple …

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Cavity Ignition In Supersonic Flow By Spark Discharge And Pulse Detonation, Timothy M. Ombrello, Campbell D. Carter, Chung-Jen Tam, Kuang-Yu Hsu Jan 2015

Cavity Ignition In Supersonic Flow By Spark Discharge And Pulse Detonation, Timothy M. Ombrello, Campbell D. Carter, Chung-Jen Tam, Kuang-Yu Hsu

United States Air Force: Publications

Ignition of an ethylene fueled cavity in a supersonic flow was achieved through the application of two energy deposition techniques: a spark discharge and pulse detonator (PD). High-frequency shadowgraph and chemiluminescence imaging showed that the spark discharge ignition was passive with the ignition kernel and ensuing flame propagation following the cavity flowfield. The PD produced a high-pressure and temperature exhaust that allowed for ignition at lower tunnel temperatures and pressures than the spark discharge, but also caused significant disruption to the cavity flowfield dynamics. Under certain cavity fueling conditions a multiple regime ignition process occurred with the PD that led …

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Characterizing Exoplanet Atmospheres: From Light-Curve Observations To Radiative-Transfer Modeling, Patricio Cubillos Vallejos Jan 2015

Characterizing Exoplanet Atmospheres: From Light-Curve Observations To Radiative-Transfer Modeling, Patricio Cubillos Vallejos

Electronic Theses and Dissertations

Multi-wavelength transit and secondary-eclipse light-curve observations are some of the most powerful techniques to probe the thermo-chemical properties of exoplanets. Although the large planet-to-star brightness contrast and few available spectral bands produce data with low signal-to-noise ratios, a Bayesian approach can robustly reveal what constraints we can set, without over-interpreting the data. Here I performed an end-to-end analysis of transiting exoplanet data. I analyzed space-telescope data for three planets to characterize their atmospheres and refine their orbits, investigated correlated noise estimators, and contributed to the development of the respective data-analysis pipelines. Chapters 2 and 3 describe the Photometry for Orbits, …

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Four Color Observations Of 2501 Lohja, Bin Li, Haibin Zhao, Hao Lu, Xianming Han Jan 2015

Four Color Observations Of 2501 Lohja, Bin Li, Haibin Zhao, Hao Lu, Xianming Han

Scholarship and Professional Work - LAS

Photometric studies of asteroid 2501 Lohja were made between 2014 June 24 and 25 using the Southeastern Association for Research in Astronomy (SARA) Kitt Peak telescope with Bessell B, V, R and I filters. We obtained a synodic period of 3.81 ± 0.01h, which is consistent with previous values.

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A Fast Visible Infrared Imaging Radiometer Suite Simulator For Cloudy Atmospheres, Chao Liu, Ping Yang, Steven Platnick, Kerry G. Meyer, Chenxi Wang, Shouguo Ding Jan 2015

A Fast Visible Infrared Imaging Radiometer Suite Simulator For Cloudy Atmospheres, Chao Liu, Ping Yang, Steven Platnick, Kerry G. Meyer, Chenxi Wang, Shouguo Ding

Department of Earth and Atmospheric Sciences: Faculty Publications

A fast instrument simulator is developed to simulate the observations made in cloudy atmospheres by the Visible Infrared Imaging Radiometer Suite (VIIRS). The correlated k distribution technique is used to compute the transmissivities associated with absorbing atmospheric gases. The bulk scattering properties of ice clouds are based on the ice model used for the Moderate Resolution Imaging Spectroradiometer Collection 6 ice cloud products, and those ofwater clouds are computedwith the Lorenz-Mie theory. Two fast radiative transfer models based on precomputed ice cloud look-up tables are used for the VIIRS solar and infrared channels. The accuracy and efficiency of the fast …

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Understanding The Gravitational-Wave Hellings And Downs Curve For Pulsar Timing Arrays In Terms Of Sound And Electromagnetic Waves, Fredrick A. Jenet, Joseph D. Romano Jan 2015

Understanding The Gravitational-Wave Hellings And Downs Curve For Pulsar Timing Arrays In Terms Of Sound And Electromagnetic Waves, Fredrick A. Jenet, Joseph D. Romano

Physics & Astronomy Faculty Publications

Searches for stochastic gravitational-wave backgrounds using pulsar timing arrays look for correlations in the timing residuals induced by the background across the pulsars in the array. The correlation signature of an isotropic, unpolarized gravitational-wave background predicted by general relativity follows the so-called Hellings and Downs curve, which is a relatively simple function of the angle between a pair of Earth-pulsar baselines. In this paper, we give a pedagogical discussion of the Hellings and Downs curve for pulsar timing arrays, considering simpler analogous scenarios involving sound and electromagnetic waves. We calculate Hellings-and-Downs-type functions for these two scenarios and develop a framework …

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The Host Galaxies Of X-Ray Selected Active Galactic Nuclei To Z = 2.5: Structure, Star Formation, And Their Relationships From Candels And Herschel/Pacs, Dale D. Kocevski, D. J. Rosario, D. H. Mcintosh, A. Van Der Wel, J. Kartaltepe, P. Lang, P. Santini, S. Wuyts, D. Lutz, M. Rafelski, C. Villforth Jan 2015

The Host Galaxies Of X-Ray Selected Active Galactic Nuclei To Z = 2.5: Structure, Star Formation, And Their Relationships From Candels And Herschel/Pacs, Dale D. Kocevski, D. J. Rosario, D. H. Mcintosh, A. Van Der Wel, J. Kartaltepe, P. Lang, P. Santini, S. Wuyts, D. Lutz, M. Rafelski, C. Villforth

Physics and Astronomy Faculty Publications

We study the relationship between the structure and star formation rate (SFR) of X-ray selected low and moderate luminosity active galactic nuclei (AGNs) in the two Chandra Deep Fields, using Hubble Space Telescope imaging from the Cosmic Assembly Near Infrared Extragalactic Legacy Survey (CANDELS) and deep far-infrared maps from the PEP+GOODS-Herschel survey. We derive detailed distributions of structural parameters and FIR luminosities from carefully constructed control samples of galaxies, which we then compare to those of the AGNs. At z ~ 1, AGNs show slightly diskier light profiles than massive inactive (non-AGN) galaxies, as well as modestly higher levels …

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Experimental Simulations Of Recurring Slope Lineae On The Surface Of Mars, Elizabeth Eddings Jan 2015

Experimental Simulations Of Recurring Slope Lineae On The Surface Of Mars, Elizabeth Eddings

Physics, Astronomy and Geophysics Honors Papers

Recurring Slope Lineae (RSL) are active surface features found on rocky Martian slopes commonly in the southern hemisphere equatorial to mid-latitude regions. These low albedo, dark streaks on Mars demonstrate seasonal characteristics;; they appear and grow darker and longer in warm months and fade to possible disappearance in colder months. One proposed mechanism for the formation and evolution of these features by McEwen et al. (2011) is the melting of subsurface water on Mars. The goal of this study was to test this hypothesis by reconstructing features similar to RSL in the lab that display the same seasonal …

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An Ion Detector For The Array For Nuclear Astrophysics And Structure With Exotic Nuclei (Anasen), Cedric Williams, K Macon, C M. Deibel, J C. Blackmon Jan 2015

An Ion Detector For The Array For Nuclear Astrophysics And Structure With Exotic Nuclei (Anasen), Cedric Williams, K Macon, C M. Deibel, J C. Blackmon

Honors Capstones

No abstract provided.

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Building A Scalable Global Data Processing Pipeline For Large Astronomical Photometric Datasets, Paul Doyle Jan 2015

Building A Scalable Global Data Processing Pipeline For Large Astronomical Photometric Datasets, Paul Doyle

Other

Astronomical photometry is the science of measuring the flux of a celestial object. Since its introduction, the CCD has been the principle method of measuring flux to calculate the apparent magnitude of an object. Each CCD image taken must go through a process of cleaning and calibration prior to its use. As the number of research telescopes increases the overall computing resources required for image processing also increases. Existing processing techniques are primarily sequential in nature, requiring increasingly powerful servers, faster disks and faster networks to process data. Existing High Performance Computing solutions involving high capacity data centres are complex …

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Study Solar Activity In The Backside Of The Sun With The Stereo Mission, Catherine A. Gibbs Jan 2015

Study Solar Activity In The Backside Of The Sun With The Stereo Mission, Catherine A. Gibbs

Summer Community of Scholars Posters (RCEU and HCR Combined Programs)

No abstract provided.

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