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The Sluggs Survey: A Comparison Of Total-Mass Profiles Of Early-Type Galaxies From Observations And Cosmological Simulations, To ∼4 Effective Radii, Sabine Bellstedt, Duncan A. Forbes, Aaron J. Romanowsky, Rhea-Silvia Remus, Adam R H Stevens, Jean P. Brodie, Adriano Poci, Richard McDermid, Adebusola B. Alabi, Leonie Chevalier, Caitlin Adams, Anna Ferré-Mateu, Asher Wasserman, Viraj Pandya 2018 Swinburne University of Technology

The Sluggs Survey: A Comparison Of Total-Mass Profiles Of Early-Type Galaxies From Observations And Cosmological Simulations, To ∼4 Effective Radii, Sabine Bellstedt, Duncan A. Forbes, Aaron J. Romanowsky, Rhea-Silvia Remus, Adam R H Stevens, Jean P. Brodie, Adriano Poci, Richard Mcdermid, Adebusola B. Alabi, Leonie Chevalier, Caitlin Adams, Anna Ferré-Mateu, Asher Wasserman, Viraj Pandya

Aaron J. Romanowsky

We apply the Jeans Anisotropic Multi-Gaussian Expansion dynamical modelling method to SAGES Legacy Unifying Globulars and GalaxieS (SLUGGS) survey data of early-type galaxies in the stellar mass range 1010 < M*/M < 1011.6 that cover a large radial range of 0.1–4.0 effective radii. We combine SLUGGS and ATLAS3D data sets to model the total-mass profiles of a sample of 21 fast-rotator galaxies, utilizing a hyperparameter method to combine the two independent data sets. The total-mass density profile slope values derived for these galaxies are consistent with those measured in the inner regions of galaxies ...


Cataclysmic Variable Stars In The Sloan Digital Sky Survey, Sinead Humphrey, Samantha Smiley, Andres Munoz, Brian Saboriendo 2018 DePaul University

Cataclysmic Variable Stars In The Sloan Digital Sky Survey, Sinead Humphrey, Samantha Smiley, Andres Munoz, Brian Saboriendo

DePaul Discoveries

The purpose of this study is to identify Cataclysmic Variables (CVs) using spectroscopic and photometric data. CVs are useful for studying plasma physics in extreme conditions such as the high temperature and strong magnetic fields seen in CV accretion disks. They are also critical for understanding the evolution of binary stars, both in the field and in globular clusters. This project used photometric and spectroscopic data from the Sloan Digital Sky Survey (SDSS) to identify and classify CVs. 6,000 objects were selected based on multi-color criteria and analyzed using spectral data. Approximately 1% of these objects in the sample ...


Planet-Driven Spiral Arms In Protoplanetary Disks. Ii. Implications, Jaehan Bae, Zhaohuan Zhu 2018 Carnegie Institution for Science

Planet-Driven Spiral Arms In Protoplanetary Disks. Ii. Implications, Jaehan Bae, Zhaohuan Zhu

Physics & Astronomy Faculty Publications

We examine whether various characteristics of planet-driven spiral arms can be used to constrain the masses of unseen planets and their positions within their disks. By carrying out two-dimensional hydrodynamic simulations varying planet mass and disk gas temperature, we find that a larger number of spiral arms form with a smaller planet mass and a lower disk temperature. A planet excites two or more spiral arms interior to its orbit for a range of disk temperatures characterized by the disk aspect ratio $0.04\leqslant {(h/r)}_{p}\leqslant 0.15$, whereas exterior to a planet's orbit multiple ...


Planet-Driven Spiral Arms In Protoplanetary Disks. I. Formation Mechanism, Jaehan Bae, Zhaohuan Zhu 2018 Carnegie Institution for Science

Planet-Driven Spiral Arms In Protoplanetary Disks. I. Formation Mechanism, Jaehan Bae, Zhaohuan Zhu

Physics & Astronomy Faculty Publications

Protoplanetary disk simulations show that a single planet can excite more than one spiral arm, possibly explaining the recent observations of multiple spiral arms in some systems. In this paper, we explain the mechanism by which a planet excites multiple spiral arms in a protoplanetary disk. Contrary to previous speculations, the formation of both primary and additional arms can be understood as a linear process when the planet mass is sufficiently small. A planet resonantly interacts with epicyclic oscillations in the disk, launching spiral wave modes around the Lindblad resonances. When a set of wave modes is in phase, they ...


A Spatially-Resolved X-Ray Spectroscopic Analysis Of The Luminous Northeastern Rim Of The Galactic Supernova Remnant W28 (G6.4-0.1), Sarah Norris, Thomas Pannuti 2018 Department of Earth and Space Sciences, College of Science

A Spatially-Resolved X-Ray Spectroscopic Analysis Of The Luminous Northeastern Rim Of The Galactic Supernova Remnant W28 (G6.4-0.1), Sarah Norris, Thomas Pannuti

Celebration of Student Scholarship Posters Archive

No abstract provided.


Low Metallicities And Old Ages For Three Ultra-Diffuse Galaxies In The Coma Cluster, Meng Gu, Charlie Conroy, David Law, Pieter van Dokkum, Renbin Yan, David Wake, Kevin Bundy, Allison Merritt, Roberto Abraham, Jielai Zhang, Matthew Bershady, Dmitry Bizyaev, Jonathan Brinkmann, Niv Drory, Kathleen Grabowski, Karen Masters, Kaike Pan, John Parejko, Anne-Marie Weijmans, Kai Zhang 2018 Harvard University

Low Metallicities And Old Ages For Three Ultra-Diffuse Galaxies In The Coma Cluster, Meng Gu, Charlie Conroy, David Law, Pieter Van Dokkum, Renbin Yan, David Wake, Kevin Bundy, Allison Merritt, Roberto Abraham, Jielai Zhang, Matthew Bershady, Dmitry Bizyaev, Jonathan Brinkmann, Niv Drory, Kathleen Grabowski, Karen Masters, Kaike Pan, John Parejko, Anne-Marie Weijmans, Kai Zhang

Physics and Astronomy Faculty Publications

A large population of ultra-diffuse galaxies (UDGs) was recently discovered in the Coma cluster. Here we present optical spectra of three such UDGs, DF 7, DF 44, and DF 17, which have central surface brightnesses of μg ≈ 24.4–25.1 mag arcsec−2. The spectra were acquired as part of an ancillary program within the SDSS-IV MaNGA Survey. We stacked 19 fibers in the central regions from larger integral field units (IFUs) per source. With over 13.5 hr of on-source integration, we achieved a mean signal-to-noise ratio in the optical of 9.5 Å−1, 7.9 ...


The Automation Of Analysis Procedures For The Citizen Cate Experiment Eclipse Data, Logan Jensen, Michael Pierce 2018 University of Wyoming

The Automation Of Analysis Procedures For The Citizen Cate Experiment Eclipse Data, Logan Jensen, Michael Pierce

Honors Theses AY 17/18

The Citizen Continental-America Telescopic Eclipse Experiment deployed 68 volunteer-operated telescope and camera systems across the United States to collect continuous data of the August 2017 solar eclipse. For any one location the eclipse lasted 2.5 minutes, but in total the nationwide CATE network collected data on the full 93 minutes of eclipse across America. The wealth of data collected contains more than 110,000 calibration and eclipse images and takes up 1.5 terabytes of memory. To become scientifically applicable, all these images needed to be corrected for systematic errors caused by the equipment and for human error. The ...


Education, Support, And Results For Wyoming Participants In The Citizen Cate (Continental-America Telescopic Eclipse) Experiment, Gabriel Miller 2018 University of Wyoming

Education, Support, And Results For Wyoming Participants In The Citizen Cate (Continental-America Telescopic Eclipse) Experiment, Gabriel Miller

Honors Theses AY 17/18

Throughout the spring and summer of 2017, the Citizen CATE (Continental- America Telescopic Eclipse) Experiment was active in Wyoming and across the contiguous United States, with the goal of achieving an unbroken line of citizen- operated telescopes and cameras along the path of totality for the August eclipse. Eleven sites were active in Wyoming, composed of teachers, students, amateur and professional astronomers, and interested members of the community. In two large educational sessions, as well as several localized practice events, these groups were trained to use the telescopes and cameras provided for them. Working closely with the National Solar Observatory ...


High-Throughput Automated Multi-Target Super-Resolution Imaging, Farzin Farzam 2018 University of New Mexico

High-Throughput Automated Multi-Target Super-Resolution Imaging, Farzin Farzam

Physics & Astronomy ETDs

Super-resolution microscopy techniques developed through the past few decades enable us to surpass the classical diffraction limit of light, and thus open new doors to investigate the formerly inaccessible world of nanometer-sized objects. Most importantly, by using super-resolution microscopy, one can visualize sub-cellular structures in the range of 10 to 200 nm. At this range, we can investigate exciting problems in biology and medicine by visualizing protein-protein interactions and spatiotemporal analysis of structures of interest on the surface or inside cells. These techniques (collectively known as nanoscopy) have a high impact on understanding and solving biological questions. This dissertation starts ...


Dispersive Quantum Interface With Atoms And Nanophotonic Waveguides, Xiaodong Qi 2018 University of New Mexico

Dispersive Quantum Interface With Atoms And Nanophotonic Waveguides, Xiaodong Qi

Physics & Astronomy ETDs

Strong coupling between atoms and light is critical for quantum information processing and precise sensing. A nanophotonic waveguide is a promising platform for realizing an atom-light interface that reaches the strong coupling regime. In this dissertation, we study the dispersive response theory of the nanowaveguide system as the means to create an entangling atom-light interface, with applications to quantum non-demolition (QND) measurement and spin squeezing.

We calculate the dyadic Green's function, which determines the scattering of light by atoms in the presence of a nanowaveguide, and thus the phase shift and polarization rotation induced on the guided light. The ...


The Nature Of Deeply Buried Ultraluminous Infrared Galaxies: A Unified Model For Highly Obscured Dusty Galaxy Emission, J. A. Marshall, Moshe Elitzur, L. Armus, T. Diaz-Santos, V. Charmandaris 2018 Glendale College

The Nature Of Deeply Buried Ultraluminous Infrared Galaxies: A Unified Model For Highly Obscured Dusty Galaxy Emission, J. A. Marshall, Moshe Elitzur, L. Armus, T. Diaz-Santos, V. Charmandaris

Physics and Astronomy Faculty Publications

We present models of deeply buried ultraluminous infrared galaxy (ULIRG) spectral energy distributions (SEDs) and use them to construct a three-dimensional diagram for diagnosing the nature of observed ULIRGs. Our goal is to construct a suite of SEDs for a very simple model ULIRG structure, and to explore how well this simple model can (by itself) explain the full range of observed ULIRG properties. We use our diagnostic to analyze archival Spitzer Space Telescope Infrared Spectrograph data of ULIRGs and find that: (1) in general, our model does provide a comprehensive explanation of the distribution of mid-IR ULIRG properties; (2 ...


Against Common Sense, Channon Visscher 2018 Dordt College

Against Common Sense, Channon Visscher

Faculty Work Comprehensive List

"Scientific inquiry... allows for the exploration of phenomena that would otherwise remain beyond human intuition."

Posting about ­­­­­­­­beauty and truth in creation from In All Things - an online journal for critical reflection on faith, culture, art, and every ordinary-yet-graced square inch of God’s creation.

https://inallthings.org/against-common-sense/


Novel Nonlinear And Quantum Devices Based On Multimode Optical Fibers, Hamed Pourbeyram 2018 University of New Mexico

Novel Nonlinear And Quantum Devices Based On Multimode Optical Fibers, Hamed Pourbeyram

Physics & Astronomy ETDs

In this dissertation, multimode optical fibers (MMFs) have been studied as a robust and practical platform for nonlinear optics and quantum optics applications, where by experimental investigations and theoretical calculations we present the quantum and nonlinear virtue of MMFs as a versatile tool for future applications. Our investigations can be summarized in three parts: At first, we have investigated stimulated Raman scattering (SRS) in a long MMF, where more than 20 orders of cascaded Raman peaks have been generated. Observation of beam clean-up despite the highly multimode nature of the fiber and such strong nonlinear interaction despite the large fiber ...


An Investigation Into The Suitability Of Sulfate-Reducing Bacteria As Models For Martian Forward Contamination, Maxwell M. W. Silver 2018 University of Arkansas, Fayetteville

An Investigation Into The Suitability Of Sulfate-Reducing Bacteria As Models For Martian Forward Contamination, Maxwell M. W. Silver

Theses and Dissertations

The NASA Planetary Protection policy requires interplanetary space missions do not compromise the target body for a current or future scientific investigation and do not pose an unacceptable risk to Earth, including biologic materials. Robotic missions to Mars pose a risk to planetary protection in the forms of forward and reverse contamination. To reduce these risks, a firm understanding of microbial response to Mars conditions is required. Sulfate-reducing bacteria are prime candidates for potential forward contamination on Mars. Understanding the potential for forward-contamination of sulfate-reducers on Mars calls for the characterization of sulfate-reducers under Mars atmosphere, temperature, and sulfate-brines. This ...


Gravity Waves Over Antarctica, Vanessa Chambers 2018 Utah State University

Gravity Waves Over Antarctica, Vanessa Chambers

Physics Capstone Project

As part of the international Antarctic Gravity Wave Instrument Network (ANGWIN) program, the Utah State University all sky IR imager has been operated at the British Antarctic Survey (BAS) Halley Station (75°36′ S, 26°12′ W) since 2012, obtaining valuable gravity wave information in the upper mesosphere and lower thermosphere region (~80 to 100 km). In this study, we have utilized a new 3D spectral analysis technique (Matsuda, et al., 2014) to quantify the horizontal phase velocity distributions of gravity waves over Antarctica. This new tool enables us to analyze extensive amounts of airglow imaging data in a relatively ...


Ri/Mom And Ri/Smom Renormalization Of Overlap Quark Bilinears On Domain Wall Fermion Configurations, Yujiang Bi, Hao Cai, Ying Chen, Ming Gong, Keh-Fei Liu, Zhaofeng Liu, Yi-Bo Yang 2018 Wuhan University, China

Ri/Mom And Ri/Smom Renormalization Of Overlap Quark Bilinears On Domain Wall Fermion Configurations, Yujiang Bi, Hao Cai, Ying Chen, Ming Gong, Keh-Fei Liu, Zhaofeng Liu, Yi-Bo Yang

Physics and Astronomy Faculty Publications

Renormalization constants (RCs) of overlap quark bilinear operators on 2+1-flavor domain wall fermion configurations are calculated by using the RI/MOM and RI/SMOM schemes. The scale independent RC for the axial vector current is computed by using a Ward identity. Then the RCs for the quark field and the vector, tensor, scalar, and pseudoscalar operators are calculated in both the RI/MOM and RI/SMOM schemes. The RCs are converted to the MS¯ scheme and we compare the numerical results from using the two intermediate schemes. The lattice size is 483 × 96 and the inverse spacing 1 ...


Cosmological Distance Measurements With Rotse Supernovae Iip And Observational Systematics On Desi Emission Line Galaxy Clustering, Govinda Dhungana 2018 Southern Methodist University

Cosmological Distance Measurements With Rotse Supernovae Iip And Observational Systematics On Desi Emission Line Galaxy Clustering, Govinda Dhungana

Physics Theses and Dissertations

Both Supernovae (SNe) and Baryon Acoustic Oscillations (BAO) surveys emerged as complementary probes of the expansion history of the universe in the last few decades. SNe Ia cosmology has reached the systematic limits in the optical surveys. The most frequently occuring SNe Type IIP are emerging as equally rich distance probes for the next generation larger surveys. In this thesis, I highlight the astrophysical observables of these events in the context of ROTSE III SN survey and using the ROTSE SNe IIP sample, I present calibration in the framework of expanding photosphere method (EPM) to use them as cosmological distance ...


3d Printed Filar Micrometer, Emily Rull 2018 Olivet Nazarene University

3d Printed Filar Micrometer, Emily Rull

Honors Program Projects

Background

Double stars are celestial objects that allow for calculating the mass of stars by assessing their orbits. Stellar mass affects every current model of stellar evolution, but the most accurate double star orbits can take decades to record. Due to the long-term nature of such observations and lack of groundbreaking research in double star studies, professional astronomers are no longer focused on making these measurements, so amateur astronomers can pick up where professionals have left off. Amateurs can only do this if they can get the equipment that they need at prices they can afford. A personally-manufactured filar micrometer ...


Hard Exclusive Pion Electroproduction At Backward Angles With Clas, K. Park, M. Guidal, R. W. Gothe, B. Pire, G. Charles, C. E. Hyde, S E. Kuhn, J. Poudel, Y. Prok 2018 Old Dominion University

Hard Exclusive Pion Electroproduction At Backward Angles With Clas, K. Park, M. Guidal, R. W. Gothe, B. Pire, G. Charles, C. E. Hyde, S E. Kuhn, J. Poudel, Y. Prok

Physics Faculty Publications

We report on the first measurement of cross sections for exclusive deeply virtual pion electroproduction off the proton, ep → e'nπ+, above the resonance region at backward pion center-of-mass angles. The ϕ∗ π-dependent cross sections were measured, from which we extracted three combinations of structure functions of the proton. Our results are compatible with calculations based on nucleon-to-pion transition distribution amplitudes (TDAs). These non-perturbative objects are defined as matrix elements of threequark-light-cone-operators and characterize partonic correlations with a particular emphasis on baryon charge distribution inside a nucleon.


Comparing Three Pulsating Subdwarf B Stars Observed By Kepler In The Open Cluster Ngc 6791, Joshua William Kern 2018 Missouri State University

Comparing Three Pulsating Subdwarf B Stars Observed By Kepler In The Open Cluster Ngc 6791, Joshua William Kern

MSU Graduate Theses

Using their entire Kepler data sets, I performed asteroseismic analyses and comparisons of three gravity (g-) mode pulsating subdwarf B (sdB) stars in the open cluster NGC 6791. I constructed light curves with a combination of long and short cadence data to span quarters 1 (Q01) through Q17 of KIC 2569576 (B3), KIC 2438324 (B4), and KIC 2437937 (B5). Rotationally induced g-mode frequency splittings were observed in each star allowing us to calculate rotation periods of 64.5 ± 8.2, 9.21 ± 0.18, and 91.3 ± 14.1 days for B3, B4, and B5, respectively. Using the observed ratio ...


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