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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.


The Stellar Populations Of Two Ultra-Diffuse Galaxies From Optical And Near-Infrared Photometry, Viraj Pandya, Aaron J. Romanowsky, Seppo Laine, Jean P. Brodie, Benjamin D. Johnson, William Glaccum, Alexa Villaume, Jean-Charles Cuillandre, Stephen Gwyn, Jessica Krick, Ronald Lasker, Ignacio Martín-Navarro, David Martinez-Delgado, Pieter G. van Dokkum 2018 University of California, Santa Cruz

The Stellar Populations Of Two Ultra-Diffuse Galaxies From Optical And Near-Infrared Photometry, Viraj Pandya, Aaron J. Romanowsky, Seppo Laine, Jean P. Brodie, Benjamin D. Johnson, William Glaccum, Alexa Villaume, Jean-Charles Cuillandre, Stephen Gwyn, Jessica Krick, Ronald Lasker, Ignacio Martín-Navarro, David Martinez-Delgado, Pieter G. Van Dokkum

Aaron J. Romanowsky

We present observational constraints on the stellar populations of two ultra-diffuse galaxies (UDGs) using optical through near-infrared (NIR) spectral energy distribution (SED) fitting. Our analysis is enabled by new Spitzer-IRAC 3.6 and 4.5 μm imaging, archival optical imaging, and the prospectorfully Bayesian SED fitting framework. Our sample contains one field UDG (DGSAT I), one Virgo cluster UDG (VCC 1287), and one Virgo cluster dwarf elliptical for comparison (VCC 1122). We find that the optical–NIR colors of the three galaxies are significantly different from each other. We infer that VCC 1287 has an old (7 ...


Upper Limits On The Presence Of Central Massive Black Holes In Two Ultra-Compact Dwarf Galaxies In Centaurus A, Karina T. Voggel, Anil C. Seth, Nadine Neumayer, Steffen Mieske, Igor Chilingarian, Christopher P. Ahn, Holger Baumgardt, Michael Hilker, Dieu D. Nguyen, Aaron J. Romanowsky, Jonelle L. Walsh, Mark den Brok, Jay Strader 2018 University of Utah

Upper Limits On The Presence Of Central Massive Black Holes In Two Ultra-Compact Dwarf Galaxies In Centaurus A, Karina T. Voggel, Anil C. Seth, Nadine Neumayer, Steffen Mieske, Igor Chilingarian, Christopher P. Ahn, Holger Baumgardt, Michael Hilker, Dieu D. Nguyen, Aaron J. Romanowsky, Jonelle L. Walsh, Mark Den Brok, Jay Strader

Aaron J. Romanowsky

The recent discovery of massive black holes (BHs) in the centers of high-mass ultra-compact dwarf galaxies (UCDs) suggests that at least some are the stripped nuclear star clusters of dwarf galaxies. We present the first study that investigates whether such massive BHs, and therefore stripped nuclei, also exist in low-mass (M < 107 M ) UCDs. We constrain the BH masses of two UCDs located in Centaurus A (UCD 320 and UCD 330) using Jeans modeling of the resolved stellar kinematics from adaptive optics data obtained with the SINFONI integral field spectrograph at the Very Large Telescope (VLT/SINFONI). No massive ...


"Water Fountain" Masers In Proto-Planetary Nebulae, Patrick R. Latimer 2018 University of New Mexico

"Water Fountain" Masers In Proto-Planetary Nebulae, Patrick R. Latimer

Jim & Mary Lois Hulsman Undergraduate Library Research Award

No abstract provided.


An Enigmatic Population Of Luminous Globular Clusters In A Galaxy Lacking Dark Matter, Pieter van Dokkum, Yotam Cohen, Shany Danieli, J. Diederik Kruijssen, Aaron Romanowsky, Allison Merritt, Roberto Abraham, Jean Brodie, Charlie Conroy, Deborah Lokhorst, Lamiya Mowla, Ewan O'Sullivan, Jielai Zhang 2018 Yale University

An Enigmatic Population Of Luminous Globular Clusters In A Galaxy Lacking Dark Matter, Pieter Van Dokkum, Yotam Cohen, Shany Danieli, J. Diederik Kruijssen, Aaron Romanowsky, Allison Merritt, Roberto Abraham, Jean Brodie, Charlie Conroy, Deborah Lokhorst, Lamiya Mowla, Ewan O'Sullivan, Jielai Zhang

Faculty Publications

We recently found an ultra diffuse galaxy (UDG) with a half-light radius of R e = 2.2 kpc and little or no dark matter. The total mass of NGC1052–DF2 was measured from the radial velocities of bright compact objects that are associated with the galaxy. Here, we analyze these objects using a combination of Hubble Space Telescope (HST) imaging and Keck spectroscopy. Their average size is pc and their average ellipticity is . From a stacked Keck spectrum we derive an age of 9 Gyr and a metallicity of [Fe/H] = −1.35 ± 0.12. Their properties are similar to ...


On The Formation Mechanisms Of Compact Elliptical Galaxies, Anna Ferré-Mateu, Duncan Forbes, Aaron Romanowsky, Joachim Janz, Christopher Dixon 2018 Swinburne University of Technology

On The Formation Mechanisms Of Compact Elliptical Galaxies, Anna Ferré-Mateu, Duncan Forbes, Aaron Romanowsky, Joachim Janz, Christopher Dixon

Faculty Publications

In order to investigate the formation mechanisms of the rare compact elliptical (cE) galaxies, we have compiled a sample of 25 cEs with good SDSS spectra, covering a range of stellar masses, sizes and environments. They have been visually classified according to the interaction with their host, representing different evolutionary stages. We have included clearly disrupted galaxies, galaxies that despite not showing signs of interaction are located close to a massive neighbour (thus are good candidates for a stripping process), and cEs with no host nearby. For the latter, tidal stripping is less likely to have happened and instead they ...


On The Formation Mechanisms Of Compact Elliptical Galaxies, Anna Ferré-Mateu, Duncan A. Forbes, Aaron J. Romanowsky, Joachim Janz, Christopher Dixon 2018 Swinburne University of Technology

On The Formation Mechanisms Of Compact Elliptical Galaxies, Anna Ferré-Mateu, Duncan A. Forbes, Aaron J. Romanowsky, Joachim Janz, Christopher Dixon

Aaron J. Romanowsky

In order to investigate the formation mechanisms of the rare compact elliptical (cE) galaxies, we have compiled a sample of 25 cEs with good SDSS spectra, covering a range of stellar masses, sizes and environments. They have been visually classified according to the interaction with their host, representing different evolutionary stages. We have included clearly disrupted galaxies, galaxies that despite not showing signs of interaction are located close to a massive neighbour (thus are good candidates for a stripping process), and cEs with no host nearby. For the latter, tidal stripping is less likely to have happened and instead they ...


Solar Eclipse, 2017 (Sc 3152), Manuscripts & Folklife Archives 2018 Western Kentucky University

Solar Eclipse, 2017 (Sc 3152), Manuscripts & Folklife Archives

MSS Finding Aids

Finding aid only for Manuscripts Small Collection 3152. Materials relating to the 2017 solar eclipse as experienced primarily in Bowling Green and Hopkinsville, Kentucky and vicinity. Includes viewing glasses, first day stamped covers, stickers, art work, photographs (in digital format), promotional materials, and impressions of the eclipse contributed as part of WKU’s Department of Library Special Collections’ “Tell Us About Your Eclipse Day” project. Also includes wristbands, handouts and volunteer information relating to an eclipse viewing event for schoolchildren held at WKU’s Smith-Houchens Stadium. Digital photographs are stored in the Photo Archives.


Effects Of Mass And Distance Uncertainties On Calculations Of Flux From Giant Molecular Clouds, Matt Coel 2018 Michigan Technological University

Effects Of Mass And Distance Uncertainties On Calculations Of Flux From Giant Molecular Clouds, Matt Coel

Dissertations, Master's Theses and Master's Reports

It is assumed that the distribution of the Milky Way cosmic rays, the cosmic ray ‘sea,’ is even throughout the Galaxy. This assumption can be tested by measuring gamma rays produced from cosmic ray interactions with Giant Molecular Clouds. The gamma ray flux depends on the mass and distance of a given molecular cloud as well as the cosmic ray flux in its vicinity. Thus a predicted gamma ray flux can be compared to actual flux data from a detector. Uncertainties from measuring the mass of and distance to the clouds are taken into account for this prediction. This report ...


Study Of The Cygnus Region With Fermi And Hawc, Andrew Robare 2018 Michigan Technological University

Study Of The Cygnus Region With Fermi And Hawc, Andrew Robare

Dissertations, Master's Theses and Master's Reports

The Cygnus Cocoon is an extended source of high-energy gamma-ray emission in the Cygnus region. The gamma-ray emission has been attributed to a volume 50pc in diameter of freshly-accelerated particles near the Supernova Remnant γ Cygni which is located 1.4kpc from the solar system [Ackermann et al., 2011], [Tibaldo et al., 2013]. Since its discovery in 2011, Fermi LAT has improved their event reconstruction to allow analysis at higher energies, and recorded six additional years of data. An analysis was performed on the entire dataset to reproduce the previous results, then expand on them with higher energies and larger ...


Energy From Active Galactic Nuclei And The Effects On Host Spiral Galaxies, Amanda Schilling 2017 University of Arkansas, Fayetteville

Energy From Active Galactic Nuclei And The Effects On Host Spiral Galaxies, Amanda Schilling

Theses and Dissertations

I have investigated the energy output of active galactic nuclei (AGN) in order to understand how these objects evolve and the impact they may have on host galaxies. First, I looked at a sample of 96 AGN at redshifts $z \sim 2, 3,$ and $4$ which have imaging and thus luminosity measurements in the $griz$ and $JHK$ observed wavebands. For these galaxies, I have co-epochal data across those bands which accounted for variability in AGN luminosity. I used the luminosity measurements in the five bands to construct spectral energy distributions (SED) in the emitted optical-UV bands for each AGN. I ...


Deep Subaru Hyper Suprime-Cam Observations Of Milky Way Satellites Columba I And Triangulum Ii*, Jeffrey Carlin, David Sand, Ricardo Muñoz, Kristine Spekkens, Beth Willman, Denija Crnojević, Duncan Forbes, Jonathan Hargis, Evan Kirby, Annika Peter, Aaron Romanowsky, Jay Strader 2017 LSST and Steward Observatory

Deep Subaru Hyper Suprime-Cam Observations Of Milky Way Satellites Columba I And Triangulum Ii*, Jeffrey Carlin, David Sand, Ricardo Muñoz, Kristine Spekkens, Beth Willman, Denija Crnojević, Duncan Forbes, Jonathan Hargis, Evan Kirby, Annika Peter, Aaron Romanowsky, Jay Strader

Faculty Publications

We present deep, wide-field Subaru Hyper Suprime-Cam photometry of two recently discovered satellites of the Milky Way (MW): Columba I (Col I) and Triangulum II (Tri II). The color–magnitude diagrams of both objects point to exclusively old and metal-poor stellar populations. We re-derive structural parameters and luminosities of these satellites, and find for Col I and for Tri II, with corresponding half-light radii of pc and pc. The properties of both systems are consistent with observed scaling relations for MW dwarf galaxies. Based on archival data, we derive upper limits on the neutral gas content of these dwarfs, and ...


Deep Subaru Hyper Suprime-Cam Observations Of Milky Way Satellites Columba I And Triangulum Ii*, Jeffrey L. Carlin, David J. Sand, Ricardo R. Muñoz, Kristine Spekkens, Beth Willman, Denija Crnojević, Duncan A. Forbes, Jonathan Hargis, Evan Kirby, Annika H.G. Peter, Aaron J. Romanowsky, Jay Strader 2017 LSST and Steward Observatory

Deep Subaru Hyper Suprime-Cam Observations Of Milky Way Satellites Columba I And Triangulum Ii*, Jeffrey L. Carlin, David J. Sand, Ricardo R. Muñoz, Kristine Spekkens, Beth Willman, Denija Crnojević, Duncan A. Forbes, Jonathan Hargis, Evan Kirby, Annika H.G. Peter, Aaron J. Romanowsky, Jay Strader

Aaron J. Romanowsky

We present deep, wide-field Subaru Hyper Suprime-Cam photometry of two recently discovered satellites of the Milky Way (MW): Columba I (Col I) and Triangulum II (Tri II). The color–magnitude diagrams of both objects point to exclusively old and metal-poor stellar populations. We re-derive structural parameters and luminosities of these satellites, and find  for Col I and  for Tri II, with corresponding half-light radii of  pc and  pc. The properties of both systems are consistent with observed scaling relations for MW dwarf galaxies. Based on archival data, we derive upper limits on the neutral gas content of these dwarfs, and ...


Initial Mass Function Variability (Or Not) Among Low-Velocity Dispersion, Compact Stellar Systems, Alexa Villaume, Jean Brodie, Charlie Conroy, Aaron Romanowsky, Pieter van Dokkum 2017 University of California, Santa Cruz

Initial Mass Function Variability (Or Not) Among Low-Velocity Dispersion, Compact Stellar Systems, Alexa Villaume, Jean Brodie, Charlie Conroy, Aaron Romanowsky, Pieter Van Dokkum

Faculty Publications

Analyses of strong gravitational lenses, galaxy-scale kinematics, and absorption-line stellar population synthesis (SPS) have all concluded that the stellar initial mass function (IMF) varies within the massive early-type galaxy (ETG) population. However, the physical mechanism that drives variation in the IMF is an outstanding question. Here we use new SPS models to consider a diverse set of compact, low-velocity dispersion stellar systems: globular clusters (GCs), an ultra-compact dwarf (UCD), and the compact elliptical (cE) galaxy M32. We compare our results to massive ETGs and available dynamical measurements. We find that the GCs have stellar mass-to-light ratios (M/L) that are ...


Initial Mass Function Variability (Or Not) Among Low-Velocity Dispersion, Compact Stellar Systems, Alexa Villaume, Jean Brodie, Charlie Conroy, Aaron J. Romanowsky, Pieter van Dokkum 2017 University of California, Santa Cruz

Initial Mass Function Variability (Or Not) Among Low-Velocity Dispersion, Compact Stellar Systems, Alexa Villaume, Jean Brodie, Charlie Conroy, Aaron J. Romanowsky, Pieter Van Dokkum

Aaron J. Romanowsky

Analyses of strong gravitational lenses, galaxy-scale kinematics, and absorption-line stellar population synthesis (SPS) have all concluded that the stellar initial mass function (IMF) varies within the massive early-type galaxy (ETG) population. However, the physical mechanism that drives variation in the IMF is an outstanding question. Here we use new SPS models to consider a diverse set of compact, low-velocity dispersion stellar systems: globular clusters (GCs), an ultra-compact dwarf (UCD), and the compact elliptical (cE) galaxy M32. We compare our results to massive ETGs and available dynamical measurements. We find that the GCs have stellar mass-to-light ratios (M/L) that are ...


Book Review: Chandra's Cosmos: Dark Matter, Black Holes, And Other Wonders Revealed By Nasa's Premier X-Ray Observatory, T. D. Oswalt 2017 Embry-Riddle Aeronautical University

Book Review: Chandra's Cosmos: Dark Matter, Black Holes, And Other Wonders Revealed By Nasa's Premier X-Ray Observatory, T. D. Oswalt

Publications

This document is Dr. Oswalt’s review of Chandra's cosmos: dark matter, black holes, and other wonders revealed by NASA's premier X-ray observatory by Wallace H. Tucker. Smithsonian Books, 2017. 266p bibl index ISBN 9781588345875, $29.95; ISBN 9781588345882 ebook, contact publiser for price.


The Sluggs Survey: Trails Of Sluggs Galaxies In A Modified Spin-Ellipticity Diagram, Sabine Bellstedt, Alister Graham, Duncan Forbes, Aaron Romanowsky, Jean Brodie, Jay Strader 2017 Swinburne University of Technology

The Sluggs Survey: Trails Of Sluggs Galaxies In A Modified Spin-Ellipticity Diagram, Sabine Bellstedt, Alister Graham, Duncan Forbes, Aaron Romanowsky, Jean Brodie, Jay Strader

Faculty Publications

We present radial tracks for four early-type galaxies with embedded intermediate-scale discs in a modified spin-ellipticity diagram. Here, each galaxy's spin and ellipticity profiles are shown as a radial track, as opposed to a single, flux-weighted aperture-dependent value as is common in the literature. The use of a single ellipticity and spin parameter is inadequate to capture the basic nature of these galaxies, which transition from fast to slow rotation as one moves to larger radii where the disc ceases to dominate. After peaking, the four galaxy's radial tracks feature a downturn in both ellipticity and spin with ...


The Sluggs Survey: Trails Of Sluggs Galaxies In A Modified Spin-Ellipticity Diagram, Sabine Bellstedt, Alister W. Graham, Duncan A. Forbes, Aaron J. Romanowsky, Jean P. Brodie, Jay Strader 2017 Swinburne University of Technology

The Sluggs Survey: Trails Of Sluggs Galaxies In A Modified Spin-Ellipticity Diagram, Sabine Bellstedt, Alister W. Graham, Duncan A. Forbes, Aaron J. Romanowsky, Jean P. Brodie, Jay Strader

Aaron J. Romanowsky

We present radial tracks for four early-type galaxies with embedded intermediate-scale discs in a modified spin-ellipticity diagram. Here, each galaxy's spin and ellipticity profiles are shown as a radial track, as opposed to a single, flux-weighted aperture-dependent value as is common in the literature. The use of a single ellipticity and spin parameter is inadequate to capture the basic nature of these galaxies, which transition from fast to slow rotation as one moves to larger radii where the disc ceases to dominate. After peaking, the four galaxy's radial tracks feature a downturn in both ellipticity and spin with ...


"Blinded By The Lines: Mid-Ir Spectra Of Mira Variables Taken With Spitzer", Dana Baylis-Aguirre, Michelle J. Creech-Eakman, Donald G. Luttermoser, Tina Gueth 2017 New Mexico Institute of Mining and Technology

"Blinded By The Lines: Mid-Ir Spectra Of Mira Variables Taken With Spitzer", Dana Baylis-Aguirre, Michelle J. Creech-Eakman, Donald G. Luttermoser, Tina Gueth

Donald G. Luttermoser

We present preliminary analysis of mid-infrared spectra of M-type and C-type Mira variables. Due to the brightness of this sample, it is straightforward to monitor changes with phase in the infrared spectral features of these regular pulsators. We have spectra of 25 Mira variables, taken with phase, using the Spitzer Infrared Spectrograph (IRS) high-resolution module. Each star has multiple spectra obtained over a one-year period from 2008-09. This is a rich, unique data set due to multiple observations of each star and the high signal-to-noise ratio from quick exposure times to prevent saturation of the IRS instrument. This paper focuses ...


Bringing Awe Down To Earth: Inspiring High Performance Through Positive Executive Coaching, Chad Thomas 2017 University of Pennsylvania

Bringing Awe Down To Earth: Inspiring High Performance Through Positive Executive Coaching, Chad Thomas

Master of Applied Positive Psychology (MAPP) Capstone Projects

What inspires and sustains high performance? Positive psychology, the scientific study of human strengths and well-being, provides evidence-based insights into the mechanisms of, and characteristics associated with, flourishing. Astronauts represent a paragon of high performance through the intensely focused preparation, passion, and perseverance required in their training and during space missions. This capstone draws on both scientific findings from positive psychology and insights from astronaut training to provide a unique lens for a positive executive coaching program. In addition to a review of relevant positive psychology research to illustrate the principles of this program, this capstone includes personal anecdotes and ...


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