Astrophysics and Astronomy Commons^™

Fast Radio Burst Energetics And Detectability From High Redshifts, Bing Zhang

Physics & Astronomy Faculty Research

We estimate the upper limit redshifts of known fast radio bursts (FRBs) using the dispersion measure (DM)-redshift (z) relation and derive the upper limit peak luminosity L p and energy E of FRBs within the observational band. The average z upper limits range from 0.17 to 3.10, the average L p upper limits range from 1.24 × 1042 erg s−1 to 7.80 × 1044 erg s−1, and the average E upper limits range from 6.91 × 1039 erg to 1.94 × 1042 erg. FRB 160102 with DM = 2596.1 ± 0.3 pc cm−3 likely has a redshift greater than 3. …

The Kelt Follow-Up Network And Transit False-Positive Catalog: Pre-Vetted False Positives For Tess, K. A. Collins, K. I. Collins, J. Pepper, J. Labadie-Bartz, K. G. Stassun, B. S. Gaudi, D. Bayliss, J. Bento, K. D. Colón, D. Feliz, D. James, M. C. Johnson, R. B. Kuhn, M. B. Lund, M. T. Penny, J. E. Rodriguez, R. J. Siverd, D. J. Stevens, X. Yao, G. Zhou, M. Akshay, G. F. Aldi, C. Ashcraft, S. Awiphan, Ö. Baştürk, D. Baker, T. G. Beatty, P. Benni, P. Berlind, G. B. Berriman, Z. Berta-Thompson, A. Bieryla, V. Bozza, S. C. Novati, M. L. Calkins, J. M. Cann, D. R. Ciardi, W. D. Cochran, David H. Cohen, D. Conti, J. R. Crepp, I. A. Curtis, G. D'Ago, K. A. Diazeguigure, C. D. Dressing, F. Dubois, E. Ellington, T. G. Ellis, G. A. Esquerdo, P. Evans, A. Friedli, A. Fukui, B. J. Fulton, E. J. Gonzales, J. C. Good, J. Gregorio, T. Gumusayak, D. A. Hancock, C. K. Harada, R. Hart, E. G. Hintz, H. Jang-Condell, E. J. Jeffery, Eric L.N. Jensen, E. Jofré, M. D. Joner, A. Kar, D. H. Kasper, B. Keten, J. F. Kielkopf, S. Komonjinda, C. Kotnik, D. W. Latham, J. Leuquire, T. R. Lewis, L. Logie, S. J. Lowther, P. J. Macqueen, T. J. Martin, D. Mawet, K. K. Mcleod, G. Murawski, N. Narita, J. Nordhausen, T. E. Oberst, C. Odden, P. A. Panka, R. Petrucci, P. Plavchan, S. N. Quinn, S. Rau, P. A. Reed, H. Relles, J. P. Renaud, G. Scarpetta, R. L. Sorber, A. D. Spencer, M. Spencer, D. C. Stephens, C. Stockdale, T.-G. Tan, M. Trueblood, P. Trueblood, S. Vanaverbeke, S. Villanueva Jr., E. M. Warner, M. L. West, S. Yalçınkaya, R. Yeigh, R. Zambelli

Physics & Astronomy Faculty Works

The Kilodegree Extremely Little Telescope (KELT) project has been conducting a photometric survey of transiting planets orbiting bright stars for over 10 years. The KELT images have a pixel scale of ~23'' pixel⁻¹—very similar to that of NASA's Transiting Exoplanet Survey Satellite (TESS)—as well as a large point-spread function, and the KELT reduction pipeline uses a weighted photometric aperture with radius 3'. At this angular scale, multiple stars are typically blended in the photometric apertures. In order to identify false positives and confirm transiting exoplanets, we have assembled a follow-up network (KELT-FUN) to conduct imaging with spatial resolution, cadence, and …

Dynamical Constraints On The Hr 8799 Planets With Gpi, Jason J. Wang, James R. Graham, Rebekah Dawson, Daniel Fabrycky, Robert J. De Rosa, Laurent Pueyo, Quinn Konopacky, Bruce Macintosh, Christian Marois, Eugene Chiang, S. Mark Ammons, Pauline Arriaga, Vanessa P. Bailey, Travis Barman, Joanna Bulger, Jeffrey Chilcote, Tara Cotten, Rene Doyon, Gaspard Duchêne, Thomas M. Esposito, Michael P. Fitzgerald, Katherine B. Follette, Benjamin L. Gerard, Stephen J. Goodsell, Alexandra Z. Greenbaum, Pascale Hibon, Li Wei Hung, Patrick Ingraham, Paul Kalas, James E. Larkin, Jérôme Maire, Franck Marchis, Kimberly Ward-Duong

Astronomy: Faculty Publications

The HR 8799 system uniquely harbors four young super-Jupiters whose orbits can provide insights into the system's dynamical history and constrain the masses of the planets themselves. Using the Gemini Planet Imager, we obtained down to one milliarcsecond precision on the astrometry of these planets. We assessed four-planet orbit models with different levels of constraints and found that assuming the planets are near 1:2:4:8 period commensurabilities, or are coplanar, does not worsen the fit. We added the prior that the planets must have been stable for the age of the system (40 Myr) by running orbit configurations from our posteriors …

Studying The Potential Of The [Oii] Emission Line As A Surrogate For Stellar Velocity Dispersion In Active Galactic Nuclei, Edward F. Donohue

Physics

We study the emission profiles of 80 active galaxies to find a surrogate for stellar velocity dispersion. We focus on the width of the emission line of once ionized oxygen, [OII], and compare our results to previous work that used [OIII]. In previous research, [OIII] was found to be a good candidate for a surrogate for stellar velocity dispersion, but analysis of the line was complicated by the presence of wings caused by gas infall and outflow in the region. Emission lines with lower ionization levels, like [OII], are known to have less artificial line-broadening from wings. The study of …

Search For A Dark Photon In Electroproduced E + E − Pairs With The Heavy Photon Search Experiment At Jlab, P. H. Adrian, N. A. Baltzell, M. Battaglieri, M. Bondí, S. Boyarinov, S. Bueltmann, G. Kalicy, H. Szumila-Vance, L. B. Weinstein, Heavy Photon Search Collaboration

Physics Faculty Publications

The Heavy Photon Search experiment took its first data in a 2015 engineering run using a 1.056 GeV, 50 nA electron beam provided by CEBAF at the Thomas Jefferson National Accelerator Facility, searching for a prompt, electroproduced dark photon with a mass between 19 and 81  MeV/c². A search for a resonance in the e⁺e⁻ invariant mass distribution, using 1.7 days (1170  nb⁻¹) of data, showed no evidence of dark photon decays above the large QED background, confirming earlier searches and demonstrating the full functionality of the experiment. Upper limits on the square …

Galaxy And Mass Assembly (Gama): Accurate Number Densities And Environments Of Massive Ultra-Compact Galaxies At 0.02 < Z < 0.3, F. Buitrago, I. Ferreras, L. S. Kelvin, I. K. Baldry, L. Davies, J. Angthopo, S. Khochfar, A. M. Hopkins, S. P. Driver, S. Brough, J. Sabater, C. J. Conselice, J. Liske, Benne W. Holwerda, M. N. Bremer, S. Phillipps, A. R. López-Sánchez, A. W. Graham

Faculty and Staff Scholarship

Context. Massive ultra-compact galaxies (MUGs) are common at z = 2-3, but very rare in the nearby Universe. Simulations predict that the few surviving MUGs should reside in galaxy clusters, whose large relative velocities prevent them from merging, thus maintaining their original properties (namely stellar populations, masses, sizes and dynamical state). Aims. Our goal is to obtain a complete census of the MUG population at 0.02 < z < 0.3, determining the number density, population properties and environment. Methods. We have taken advantage of the high-completeness, large-area spectroscopic GAMA survey, complementing it with deeper imaging from the KiDS and VIKING surveys. We find a set of 22 bona-fide MUGs, defined as having high stellar mass (> 8 × 1010 M™) and compact size (Re < 2 kpc). An additional set of seven lower-mass objects (6 × 1010 < Ma/M™ < 8 × 1010) are also potential candidates according to typical mass uncertainties. Results. The comoving number density of MUGs at low redshift (z < 0.3) is constrained at (1.0 ± 0.4)×10-6 Mpc-3, consistent with galaxy evolution models. However, we find a mixed distribution of old and young galaxies, with a quarter of the sample representing (old) relics. MUGs have a predominantly early or swollen disk morphology (Sérsic index 1 < n < 2.5) with high stellar surface densities (â Σea ∼1010 M™ Kpc-2). Interestingly, a large fraction feature close companions- A t least in projection-suggesting that many (but not all) reside in the central regions of groups. Halo masses show these galaxies inhabit average-mass groups. Conclusions. As MUGs are found to be almost equally distributed among environments of different masses, their relative fraction is higher in more massive overdensities, matching the expectations that some of these galaxies fell in these regions at early times. However, there must be another channel leading some of these galaxies to an abnormally low merger history because our sample shows a number of objects that do not inhabit particularly dense environments.

Writing And Designing A Chapter On Mercury And Pluto For The Textbook Exploring The Planets (Explanet.Info), Braxton Clark Spilker

Theses and Dissertations

Exploring the Planets (http://explanet.info) is a free online college textbook covering thebasic concepts of planetary science emphasizing the character and evolution of the planetarybodies in the Solar System. The latest edition (3rd edition) was published online in 2007 by EricH Christiansen. Since the release of the third edition, two important planetary missions havebeen completed: MESSENGER (to Mercury) and New Horizons (to Pluto). These missionsprovided new information and fundamental insights into these planetary bodies, which have notyet been included in Exploring the Planets. The modern results based on recent investigations ofMercury and Pluto are critical for our understanding of the nature …

A Statistical Analysis Of Steve, Bea Gallardo‐Lacourt, Y. Nishimura, E. Donovan, G. W. Gillies, W. E. Archer, Omar A. Nava, E. L. Spanswick

Faculty Publications

There has been an exciting recent development in auroral research associated with the discovery of a new subauroral phenomenon called STEVE (Strong Thermal Emission Velocity Enhancement). Although STEVE has been documented by amateur night sky watchers for decades, it is as yet an unidentified upper atmosphere phenomenon. Observed first by amateur auroral photographers, STEVE appears as a narrow luminous structure across the night sky over thousands of kilometers in the east‐west direction. In this paper, we present the first statistical analysis of the properties of 28 STEVE events identified using Time History of Events and Macroscale Interactions during Substorms (THEMIS) …

The 55 Cancri System Reassessed, Vincent Bourrier, Xavier Dumusque, Caroline Dorn, Gregory W. Henry, Nicola Astudillo-Defru, Javiera Rey, Björn Benneke, Guillaume Hébrard, Christophe Lovis, Brice-Olivier Demory, C. Moutou, David Ehrenreich

Information Systems and Engineering Management Research Publications

Orbiting a bright, nearby star the 55 Cnc system offers a rare opportunity to study a multiplanet system that has a wide range of planetary masses and orbital distances. Using two decades of photometry and spectroscopy data, we have measured the rotation of the host star and its solar-like magnetic cycle. Accounting for this cycle in our velocimetric analysis of the system allows us to revise the properties of the outermost giant planet and its four planetary companions. The innermost planet 55 Cnc e is an unusually close-in super-Earth, whose transits have allowed for detailed follow-up studies. Recent observations favor …

Testing Velocity-Dependent Cpt-Violating Gravitational Forces With Radio Pulsars, Lijing Shao, Quentin G. Bailey

Publications

In the spirit of effective field theory, the standard-model extension (SME) provides a comprehensive framework to systematically probe the possibility of Lorentz/CPT violation. In the pure gravity sector, operators with mass dimension larger than 4, while in general being advantageous to short-range experiments, are hard to investigate with systems of astronomical size. However, there is exception if the leading-order effects are CPT-violating and velocity-dependent. Here we study the lowest-order operators in the pure gravity sector that violate the CPT symmetry with carefully chosen relativistic binary pulsar systems. Applying the existing analytical results to the dynamics of a binary orbit, we …

Results Of Webt, Vlba And Rxte Monitoring Of 3c 279 During 2006-2007, Niall Smith, Et. Al.

Blackrock Castle Observatory Publications

Context. The quasar 3C 279 is among the most extreme blazars in terms of luminosity and variability of flux at all wavebands. Its variations in flux and polarization are quite complex and therefore require intensive monitoring observations at multiple wavebands to characterise and interpret the observed changes.

Aims. In this paper, we present radio-to-optical data taken by the WEBT, supplemented by our VLBA and RXTE observations, of 3C 279. Our goal is to use this extensive database to draw inferences regarding the physics of the relativistic jet.

Methods. We assemble multifrequency light curves with data from 30 ground-based observatories and …

P-43 Doing Astronomy With Gravitational Waves, Tiffany Summerscales

Celebration of Research and Creative Scholarship

With the first detection of gravitational waves on September 14, 2015, the new era of gravitational wave astronomy began. Gravitational wave detections, along with observations made by optical telescopes, have given us new information about the universe. This includes new estimates of the numbers of black holes in the universe and their properties, as well as confirming theories about the sources of some gamma ray bursts and how those sources produce heavy elements.

Applications Of Nasa Earth Observations For Monitoring Forest Loss In The Madre De Dios Region Of Peru, Andrea Nicolau, Kelsey Herndon, Africa Flores, Robert Griffin

Von Braun Symposium Student Posters

No abstract provided.

Electrical Characteristics Of A Balloon-Borne Radiation Instrument, Elena Pradhan, Jared Fuchs

Von Braun Symposium Student Posters

No abstract provided.

Mission Overview For A Cislunar Gamma-Ray Burst Detector, Chandler Ellis, Jared Fuchs

Von Braun Symposium Student Posters

No abstract provided.

Anticoincidence Detector Performance Analysis, Christopher Helmerich, Erik Korzon

Von Braun Symposium Student Posters

No abstract provided.

Radiation Detection At Ultra-High Altitudes, Samantha Johnson, Christopher Helmerich

Von Braun Symposium Student Posters

No abstract provided.

Evaluating Methods For Identifying And Monitoring Factors In The Puget Sound That Indicate Eutrophication And Hypoxia, Christine Evans, Emily Kinkle, Helen Baldwin, Yu Han, Robert Griffin

Von Braun Symposium Student Posters

No abstract provided.

Simulation Of An X-Ray/Gamma-Ray Polarization Cubesat, Jared Fuchs, Lucas Capps, Jeren Suzuki

Von Braun Symposium Student Posters

No abstract provided.

Comparison Of Raman And Broadband Spectroscopy Methods For Material Identification, Jennifer Miller

Von Braun Symposium Student Posters

No abstract provided.