Astrophysics and Astronomy Commons^™

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

Faculty Publications

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 BHs …

Seeing An Exoplanet, Leo Moraczewski

Celebrating Scholarship and Creativity Day (2018-)

In my experiment, I used the telescopes at the Saint John’s Observatory to measure the brightness of three stars that were expected to have exoplanets orbiting them. I was unable to take enough data on two of the stars, but was able to confirm the existence of an exoplanet around the third, HD189733.

Lunar Ice Cube: Development Of A Numerical Model For Attitude Control, Alexander Roberts, Benjamin Malphrus, Kevin Brown

Celebration of Student Scholarship Poster Sessions Archive

No abstract provided.

Msu And Citizen Cate: A High Definition Look At The Sun’S Inner Corona During The 2017 Solar Eclipse Over Hopkinsville, Kentucky., Jessie Anderson, Ethan Caudill

Celebration of Student Scholarship Poster Sessions Archive

No abstract provided.

Primordial Black Hole Atoms, David Zwick, Tyler Hanover, Brian Nepper

STEM Student Research Symposium Posters

Primordial black holes are thought to have been formed at the early stages of the universe in the presence of non-homogeneous density distributions of dark matter. We are working under the assumption that dark matter consists of elementary low mass particles, specifically, spin 1/2 fermions. We further assume that dark matter is electrically neutral, thus its main interaction is gravitational. We investigate dark matter spin 1/2 fermions in orbit around a black hole atom and consider mass ranges for which the quantum description is appropriate. Solutions to the Dirac equation are utilized to describe the radial mass distribution of primordial …

Illuminating Low Surface Brightness Galaxies With The Hyper Suprime-Cam Survey, Johnny P. Greco, Jenny E. Greene, Michael A. Strauss, Lauren A. Macarthur, Xzavier Flowers, Andy D. Goulding, Song Huang, Ji Hoon Kim, Yutaka Komiyama, Alexie Leauthaud, Lukas Leisman, Robert H. Lupton, Cristobal Sifon, Shiang-Yu Wang

Aerospace, Physics, and Space Science Faculty Publications

We present a catalog of extended low surface brightness galaxies (LSBGs) identified in the Wide layer of the Hyper Suprime-Cam Subaru Strategic Program (HSC-SSP). Using the first ∼200 deg2 of the survey, we have uncovered 781 LSBGs, spanning red (g − I >/0.64) and blue (g − i < 0.64) colors and a wide range of morphologies. Since we focus on extended galaxies (reff = 2 5–14″), our sample is likely dominated by low- redshift objects. We define LSBGs to have mean surface brightnesses m¯ eff (g) > 24.3 mag arcsec−2, which allows nucleated galaxies into our sample. As a result, the central surface brightness distribution spans a wide range of μ0(g) = 18–27.4 mag arcsec−2, with 50% and 95% of galaxies fainter than 24.3 and 22 mag arcsec−2, respectively. Furthermore, the surface brightness distribution is a strong function of …

The Green Bank Northern Celestial Cap Pulsar Survey. Ii. The Discovery And Timing Of 10 Pulsars, A. M. Kawash, M. A. Mclaughlin, Louis Percy Dartez, David Day, Anthony J. Ford, Jesus Hinojosa, Fredrick A. Jenet, Sean Leake, Grady Lunsford, Alberto Mata

Physics & Astronomy Faculty Publications

We present timing solutions for 10 pulsars discovered in 350 MHz searches with the Green Bank Telescope. Nine of these were discovered in the Green Bank Northern Celestial Cap survey and one was discovered by students in the Pulsar Search Collaboratory program during an analysis of drift-scan data. Following the discovery and confirmation with the Green Bank Telescope, timing has yielded phase-connected solutions with high-precision measurements of rotational and astrometric parameters. Eight of the pulsars are slow and isolated, including PSR J0930-2301, a pulsar with a nulling fraction lower limit of ∼30% and a nulling timescale of seconds to minutes. …

Does The Black Hole Shadow Probe The Event Horizon Geometry?, Pedro V. P. Cunha, Carlos A. R. Herdeiro, Maria J. Rodriguez

All Physics Faculty Publications

There is an exciting prospect of obtaining the shadow of astrophysical black holes (BHs) in the near future with the Event Horizon Telescope. As a matter of principle, this justifies asking how much one can learn about the BH horizon itself from such a measurement. Since the shadow is determined by a set of special photon orbits, rather than horizon properties, it is possible that different horizon geometries yield similar shadows. One may then ask how sensitive is the shadow to details of the horizon geometry? As a case study, we consider the double Schwarzschild BH and analyze the impact …

Infrared Properties Of Stars In The Bulge Asymmetries And Dynamical Evolution Survey, Eddie Hilburn

Physics & Astronomy ETDs

The Bulge Asymmetries and Dynamical Evolution (BAaDE) survey is an SiO maser survey of 28,062 infrared-selected evolved stars primarily in the Galactic plane. By cross-matching the BAaDE target sources with nine different infrared catalogs, we have constructed a catalog with wavelength coverage from 0.71 to 80 m. Using this catalog, we fit the data for each source to a model spectral energy distribution (SED) generated with the radiation transport program DUSTY in order to obtain characteristics such as bolometric flux, source effective temperature, and the optical depth of the circumstellar envelope.

The overall goal of the BAaDE survey is to …

Breaking The Habit: The Peculiar 2016 Eruption Of The Unique Recurrent Nova M31n 2008-12a, M. Henze, T. D. Oswalt, M. J. Darnley, S. C. Williams, M. Kato, Et Al.

Publications

Since its discovery in 2008, the Andromeda galaxy nova M31N 2008-12a has been observed in eruption every single year. This unprecedented frequency indicates an extreme object, with a massive white dwarf and a high accretion rate, which is the most promising candidate for the single-degenerate progenitor of a Type Ia supernova known to date. The previous three eruptions of M31N 2008-12a have displayed remarkably homogeneous multiwavelength properties: (i) from a faint peak, the optical light curve declined rapidly by two magnitudes in less than two days, (ii) early spectra showed initial high velocities that slowed down significantly within days and …

High Energy Lightning Emission Network (Helen), Everett Cavanaugh, Christopher Helmerich, Elena Pradhan, Jered Hunn, Frederick Snopl, Kayla Capitan, Sarah Dangelo, Jennifer Miller, Faith Gonzalez, Alex Mcleod, Cory Wolfe, Sean Widmier, Ian Slamen

Research Horizons Day Posters

No abstract provided.

Improving Low-Spatial Frequency Figure Errors In Full-Shell X-Ray Optics, Samantha Johnson

Research Horizons Day Posters

No abstract provided.

Quantum Phase Space Representations And Their Negativities, Ninnat Dangniam

Physics & Astronomy ETDs

A classical simulation scheme of quantum computation given a restricted set of states and measurements may be---occasionally, but only occasionally---interpreted naturally as a statistical simulation of positive quasi-probability distributions on a phase space. In this dissertation, we explore phase space representations for finite-dimensional quantum systems and their negativities beyond the usual analogues of the Wigner function.

The first line of study focuses on a characterization tool for valid quasi-probability distributions of (possibly mixed) quantum states. A quantum generalization of Bochner's theorem from classical probability theory simultaneously characterizes both the set of valid Wigner functions and the subset of positive ones. …

Geometric Design, John Marceaux

Honors Capstones

No abstract provided.

Strange And Non-Strange Distributions From The Collider Data, Sergey Alekhin, Johannes Blümlein, Sergey Kulagin, Sven-Olaf Moch, Roberto Petti

Faculty Publications

We check the stability of the ABMP16 fit with respect to modifications of quark PDFs suggested in the recent literature: the strange sea enhancement and a positive non-vanishing d/u ratio at x → 1. These possibilities are examined using test versions of the ABMP16 PDF fit which demonstrate no need of those changes. Furthermore, we localize peculiar features in other analyses which are responsible for a different behaviour of the PDFs obtained. The strange sea enhancement can be explained by a choice of the PDF shapes being not flexible enough and therefore leading to an over-suppressed d-quark distribution. This …

A Strong Limit On The Very-High-Energy Emission From Grb 150323a, P. T. Reynolds, Et Al

Physical Sciences Publications

On 2015 March 23, the Very Energetic Radiation Imaging Telescope Array System (VERITAS) responded to a Swift-Burst Alert Telescope (BAT) detection of a gamma-ray burst, with observations beginning 270 s after the onset of BAT emission, and only 135 s after the main BAT emission peak. No statistically significant signal is detected above 140 GeV. The VERITAS upper limit on the fluence in a 40-minute integration corresponds to about 1% of the prompt fluence. Our limit is particularly significant because the very-high-energy (VHE) observation started only ~2 minutes after the prompt emission peaked, and Fermi-Large Area Telescope observations …

Galaxy And Mass Assembly (Gama): Impact Of The Group Environment On Galaxy Star Formation, S. Barsanti, M. S. Owers, S. Brough, L. J.M. Davies, S. P. Driver, M. L.P. Gunawardhana, Benne W. Holwerda, J. Liske, J. Loveday, K. A. Pimbblet, A. S.G. Robotham, E. N. Taylor

Faculty and Staff Scholarship

We explore how the group environment may affect the evolution of star-forming galaxies. We select 1197 Galaxy And Mass Assembly groups at 0.05 ≤ z ≤ 0.2 and analyze the projected phase space (PPS) diagram, i.e., the galaxy velocity as a function of projected group-centric radius, as a local environmental metric in the low-mass halo regime 1012 ≤ (M 200/M o) < 1014. We study the properties of star-forming group galaxies, exploring the correlation of star formation rate (SFR) with radial distance and stellar mass. We find that the fraction of star-forming group members is higher in the PPS regions dominated by recently accreted galaxies, whereas passive galaxies dominate the virialized regions. We observe a small decline in specific SFR of star-forming galaxies toward the group center by a factor ∼1.2 with respect to field galaxies. Similar to cluster studies, we conclude for low-mass halos that star-forming group galaxies represent an infalling population from the field to the halo and show suppressed star formation.

Planetary Candidates Observed By Kepler. Viii. A Fully Automated Catalog With Measured Completeness And Reliability Based On Data Release 25, Susan E. Thompson, Jeffrey L. Coughlin, Kelssey Hoffman, Fergal Mullally, Jessie L. Christiansen, Christopher J. Burke, Steve Bryson, Natalie Batalha, Michael R. Haas, Joseph Catanzarite, Jason F. Rowe, Geert Barentsen, Douglas A. Caldwell, Bruce D. Clarke, Jon M. Jenkins, Jie Li, David W. Latham, Jack J. Lissauer, Savita Mathur, Robert L. Morris, Shawn E. Seader, Jeffrey C. Smith, Todd C. Klaus, Joseph D. Twicken, Jeffrey E. Van Cleve, Bill Wohler, Rachel Akeson, David R. Ciardi, William D. Cochran, Christopher E. Henze, Steve B. Howell

Physics & Astronomy Faculty Research

We present the Kepler Object of Interest (KOI) catalog of transiting exoplanets based on searching 4 yr of Kepler time series photometry (Data Release 25, Q1–Q17). The catalog contains 8054 KOIs, of which 4034 are planet candidates with periods between 0.25 and 632 days. Of these candidates, 219 are new, including two in multiplanet systems (KOI-82.06 and KOI-2926.05) and 10 high-reliability, terrestrial-size, habitable zone candidates. This catalog was created using a tool called the Robovetter, which automatically vets the DR25 threshold crossing events (TCEs). The Robovetter also vetted simulated data sets and measured how well it was able to separate …

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

2018 Award Winners

No abstract provided.

U-Band Measurement Of Star Formation In Cluster Galaxies, Wayne Barkhouse, Gihan Gamage, Sandanuwa Kalawila, Madina Sultanova, Dean Smith, Elijah Mathews, Haylee Archer

Physics Faculty Publications

We propose to obtain deep U-band observations of 14 low-redshift (z ≤ 0.06) galaxy clusters using the WIYN 0.9m+HDI telescope/detector to complete our survey to probe star formation of galaxies in high-density environments. These observations, combined with previously obtained data of 11 clusters observed using the same telescope+detector, will give us a statistically significant sample for the Ph.D. dissertation of co-I Gihan Gamage. Clusters are selected from 57 clusters in which we have obtained deep B- and R-band data using the KPNO 0.9m+MOSA. U-band data will allow us to explore relative changes in the luminosity function for the U- and …

Mapping Star Formation From The Core To The Outskirts Of Galaxy Clusters, Wayne Barkhouse, Gihan Gamage, Sandanuwa Kalawila, Madina Sultanova, Dean Smith, Elijah Mathews, Haylee Archer

Physics Faculty Publications

We propose for time to complete our u- and r-band imaging program of 30 low-redshift (z ≤ 0.03) galaxy clusters using the CTIO Blanco 4m+DECam telescope/detector combination. These data will allow us to probe star formation from the cluster core to the infall region, and complete the acquisition of observations for the Ph.D. dissertation of Gihan Gamage (University of North Dakota). The deep u- and r-band data will allow us to explore relative changes in the luminosity function, dwarf-to-giant ratio, blue fraction, and galaxy morphological type as a function of cluster-centric radius for a statistically significant sample of 30 clusters. …

Sdss-Iv Manga: Star Formation Cessation In Low-Redshift Galaxies. I. Dependence On Stellar Mass And Structural Properties, Enci Wang, Cheng Li, Ting Xiao, Lin Lin, Matthew Bershady, David R. Law, Michael Merrifield, Sebastian F. Sanchez, Rogemar A. Riffel, Rogerio Riffel, Renbin Yan

Physics and Astronomy Faculty Publications

We investigate radial gradients in the recent star formation history (SFH) of 1917 galaxies with 0.01 < z < 0.14 from the Mapping Nearby Galaxies at Apache Point Observatory project. For each galaxy, we obtain two-dimensional maps and radial profiles for three spectroscopically measured parameters that are sensitive to the recent SFH: D_n (4000) (the 4000 Å break), EW(Hδ_A), and EW(Hα) (the equivalent width of the Hδ absorption and the Hα emission line). The majority of the spaxels are consistent with models of a continuously declining star formation rate, indicating that starbursts occur rarely in local galaxies with regular morphologies. We classify the galaxies into three classes: fully star-forming (SF), partly quenched (PQ), and totally quenched (TQ). The galaxies that are less massive than 10¹⁰ M_{⊙ …}

Galaxy And Mass Assembly (Gama): The Effect Of Galaxy Group Environment On Active Galactic Nuclei, Yjan A. Gordon, Kevin A. Pimbblet, Matt S. Owers, Joss Bland-Hawthorn, Sarah Brough, Michael J.I. Brown, Michelle E. Cluver, Scott M. Croom, Benne W. Holwerda, Jonathan Loveday, Smriti Mahajan, Lingyu Wang

Faculty and Staff Scholarship

In galaxy clusters, efficiently accreting active galactic nuclei (AGNs) are preferentially located in the infall regions of the cluster projected phase-space, and are rarely found in the cluster core. This has been attributed to both an increase in triggering opportunities for infalling galaxies, and a reduction of those mechanisms in the hot, virialized, cluster core. Exploiting the depth and completeness (98 per cent at r < 19.8mag) of the Galaxy And Mass Assembly survey (GAMA), we probe down the group halo mass function to assess whether AGNs are found in the same regions in groups as they are in clusters. We select 451 optical AGNs from 7498 galaxies with log10(M*/M⊙) > 9.9 in 695 groups with 11.53 ≤ log10(M200/M⊙) ≤ 14.56 at < 0.15. By analysing the projected phase-space positions of these galaxies, we demonstrate that when split both radially, and into physically derived infalling and core populations, AGN position within group projected phase-space is dependent on halo mass. For groups with log10(M200/M⊙) > 13.5,AGNs are preferentially found in the infalling galaxy populationwith 3.6s confidence. At lower halo masses, we observe no difference in AGN fraction between core …

Effects Of Radiation On Neurite Morphology And Cytoskeleton Structure, Melissa Sassman

Student Scholarship

Long-term manned space exploration to the moon, Mars, and other areas beyond Earth's protective magnetic field poses possible acute and late central nervous systems (CNS) risks. Of particular concern for astronauts is exposure to high atomic number, high energy particles known as HZE particles, a component of galactic cosmic radiation (GCR). Although NASA has radiation safety requirements, the possible effects of GCR and HZE particles on the central nervous systems of astronauts remains unknown. Understanding the risks and effects of galactic cosmic radiation and HZE particles on the central nervous system will allow for safer space exploration.

Additionally, and perhaps …

Some Results From The Lariat Experiment, Derek Walker

Honors Capstones

No abstract provided.

Radiomic Feature Analysis And Classification Of Tumors For Serial Pre-Clinical Spect/Ct Data, Megan Chesal

Honors Capstones

No abstract provided.

Spatiotemporal Properties Of Solid State Harmonics, Christopher Abadie

Honors Capstones

No abstract provided.

An L Band Spectrum Of The Coldest Brown Dwarf, Caroline V. Morley, Andrew J. Skemer, Katelyn N. Allers, Mark S. Marley, Jacqueline K. Faherty, Channon Visscher, Samuel A. Beiler, Brittany E. Miles, Roxana Lupu, Richard S. Freedman, Jonathan J. Fortney, Thomas R. Geballe, Gordon L. Bjoraker

Faculty Work Comprehensive List

The coldest brown dwarf, WISE 0855, is the closest known planetary-mass, free-floating object and has a temperature nearly as cold as the solar system gas giants. Like Jupiter, it is predicted to have an atmosphere rich in methane, water, and ammonia, with clouds of volatile ices. WISE 0855 is faint at near-infrared wavelengths and emits almost all its energy in the mid-infrared. Skemer et al. (2016) presented a spectrum of WISE 0855 from 4.5–5.1 µm (M band), revealing water vapor features. Here, we present a spectrum of WISE 0855 in L band, from 3.4–4.14 µm. We present a set of …

Astr 405

Department of Physics and Astronomy: Syllabi

No abstract provided.

Development Of A Real-Time Auralization System For Assessment Of Vocal Effort In Virtual-Acoustic Environments, Jennifer Kay Whiting

Theses and Dissertations

This thesis describes the development of the real-time convolution system (RTCS) for a little-studied talker/listener in virtual acoustic environments. We include descriptions of the high-resolution directivity measurements of human speech, the RTCS system components, the measurement and characterization of oral-binaural room impulse responses (OBRIRs) for a variety of acoustic environments, and the compensation filter necessary for its validity. In addition to incorporating the high-resolution directivity measurements, this RTCS improved on that developed by Cabrera et al. [1] through the derivation and inclusion of the compensation filter. Objective measures in the time- and frequency-domains, as well as subjective measures, were developed …