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P-13 Astronomy From Ripples In Spacetime, Tiffany Summerscales 2019 Andrews University

P-13 Astronomy From Ripples In Spacetime, Tiffany Summerscales

Celebration of Research and Creative Scholarship

The LIGO and Virgo detectors have made a total of 11 confirmed measurements of gravitational waves, the faint ripples in the fabric of spacetime predicted by Einstein’s theory of general relativity. Ten of these gravitational wave events were caused by the inspiral, collision, and merging of a pair of black holes and the remaining event by a pair of neutron stars. These measurements have helped us learn about the objects that produced the gravitational waves. Regular candidate detections are now shared in real time with both astronomers and the public.


Galaxy And Mass Assembly: A Comparison Between Galaxy-Galaxy Lens Searches In Kids/Gama, Shawn Knabel, Benne Holwerda 2019 University of Louisville

Galaxy And Mass Assembly: A Comparison Between Galaxy-Galaxy Lens Searches In Kids/Gama, Shawn Knabel, Benne Holwerda

Posters-at-the-Capitol

Strong gravitational lenses are cases where a distant background galaxy is located directly behind a massive foreground galaxy, whose gravity causes the light from the background galaxy to bend around the foreground galaxy. In addition to being visually stunning, these rare events are useful laboratories for furthering our understanding of gravity and cosmology and to determine properties, such as the mass and dark matter content, of the lensing galaxies themselves. The trouble is finding enough of these strong gravitational lenses for further study. The immensity of the catalogs being collected by state-of-the-art telescopes requires equally innovative methods for interpreting that ...


Synchrotron Self-Compton Emission From External Shocks As The Origin Of The Sub-Tev Emission In Grb 180720b And Grb 190114c, Xiang-Yu Wang, Ruo-Yu Liu, Hai-Ming Zhang, Shao-Qiang Xi, Bing Zhang 2019 Nanjing University

Synchrotron Self-Compton Emission From External Shocks As The Origin Of The Sub-Tev Emission In Grb 180720b And Grb 190114c, Xiang-Yu Wang, Ruo-Yu Liu, Hai-Ming Zhang, Shao-Qiang Xi, Bing Zhang

Physics & Astronomy Faculty Publications

Recently, very high-energy photons above 100 GeV were reported to be detected from GRB 190114C and GRB 180720B at, respectively, 100–1000 s and 10 hr after the burst. We model the available broadband data of both GRBs with the synchrotron plus synchrotron self-Compton (SSC) emission of the afterglow shocks. We find that the sub-TeV emission of GRB 180720B can be interpreted as the SSC emission from afterglow shocks expanding in a constant-density circumburst medium. The SSC emission of GRB 190114C dominates over the synchrotron component from GeV energies at ~100 s, which can explain the possible hard spectrum of ...


"Double-Tracking" Characteristics Of The Spectral Evolution Of Grb 131231a: Synchrotron Origin?, Liang Li, Jin-Jun Geng, Yan-Zhi Meng, Xue-Feng Wu, Yong-Feng Huang, Yu Wang, Rahim Moradi, Lucas Uhm, Bing Zhang 2019 Chinese Academy of Sciences

"Double-Tracking" Characteristics Of The Spectral Evolution Of Grb 131231a: Synchrotron Origin?, Liang Li, Jin-Jun Geng, Yan-Zhi Meng, Xue-Feng Wu, Yong-Feng Huang, Yu Wang, Rahim Moradi, Lucas Uhm, Bing Zhang

Physics & Astronomy Faculty Publications

The characteristics of the spectral evolution of the prompt emission of gamma-ray bursts (GRBs), which are closely related to the radiation mechanism (synchrotron or photosphere), are still an unsolved subject. Here, by performing the detailed time-resolved spectral fitting of GRB 131231A, which has a very bright and well-defined single pulse, some interesting spectral evolution features have been found. (i) Both the low-energy spectral index α and the peak energy E p exhibit the "flux-tracking" pattern ("double-tracking" characteristics). (ii) The parameter relations, i.e., F (the energy flux)-α, F–E p, and E p–α, along with the analogous Yonetoku ...


Diagnosing 0.1–10 Au Scale Morphology Of The Fu Ori Disk Using Alma And Vlti/Gravity, Hauyu Baobab Liu, Antoine Merand, Joel D. Green, Sebastian Perez, Antonio S. Hales, Yao-Lun Yang, Michael M. Dunham, Yasuhiro Hasegawa, Thomas Henning, Roberto Galvin-Madrid, Agnes Kospal, Michihiro Takami, Eduardo I. Vorobyov, Zhaohuan Zhu 2019 Academia Sinica Institute of Astronomy and Astrophysics

Diagnosing 0.1–10 Au Scale Morphology Of The Fu Ori Disk Using Alma And Vlti/Gravity, Hauyu Baobab Liu, Antoine Merand, Joel D. Green, Sebastian Perez, Antonio S. Hales, Yao-Lun Yang, Michael M. Dunham, Yasuhiro Hasegawa, Thomas Henning, Roberto Galvin-Madrid, Agnes Kospal, Michihiro Takami, Eduardo I. Vorobyov, Zhaohuan Zhu

Physics & Astronomy Faculty Publications

We report new Atacama Large Millimeter/submillimeter Array Band 3 (86–100 GHz; ~80 mas angular resolution) and Band 4 (146–160 GHz; ~50 mas angular resolution) observations of the dust continuum emission toward the archetypal and ongoing accretion burst young stellar object FU Ori, which simultaneously covered its companion, FU Ori S. In addition, we present near-infrared (2–2.45 μm) observations of FU Ori taken with the General Relativity Analysis via VLT InTerferometrY (GRAVITY; ~1 mas angular resolution) instrument on the Very Large Telescope Interferometer (VLTI). We find that the emission in both FU Ori and FU Ori ...


The Frb 121102 Host Is Atypical Among Nearby Fast Radio Bursts, Ye Li, Bing Zhang, Kentaro Nagamine, Jingjing Shi 2019 Peking University

The Frb 121102 Host Is Atypical Among Nearby Fast Radio Bursts, Ye Li, Bing Zhang, Kentaro Nagamine, Jingjing Shi

Physics & Astronomy Faculty Publications

We search for host galaxy candidates of nearby fast radio bursts (FRBs), FRB 180729.J1316+55, FRB 171020, FRB 171213, FRB 180810.J1159+83, and FRB 180814.J0422+73 (the second repeating FRB). We compare the absolute magnitudes and the expected host dispersion measure DMhost of these candidates with that of the first repeating FRB, FRB 121102, as well as those of long gamma-ray bursts (LGRBs) and superluminous supernovae (SLSNe), the proposed progenitor systems of FRB 121102. We find that while the FRB 121102 host is consistent with those of LGRBs and SLSNe, the nearby FRB host candidates, at least ...


Descriptive Astronomy I: The Solar System (Csu), Rosa Williams, Kimberly Shaw 2019 Columbus State University

Descriptive Astronomy I: The Solar System (Csu), Rosa Williams, Kimberly Shaw

Physics and Astronomy Grants Collections

This Grants Collection for Descriptive Astronomy I was created under a Round Thirteen ALG Textbook Transformation Grant.

Affordable Learning Georgia Grants Collections are intended to provide faculty with the frameworks to quickly implement or revise the same materials as a Textbook Transformation Grants team, along with the aims and lessons learned from project teams during the implementation process.

Each collection contains the following materials:

  • Linked Syllabus
  • Initial Proposal
  • Final Report


One Story, Told Week By Week: Episodic Podcast Storytelling And The Habitat, Charlotte De Beauvoir 2019 Los Andes University, Bogotá

One Story, Told Week By Week: Episodic Podcast Storytelling And The Habitat, Charlotte De Beauvoir

RadioDoc Review

The rise and success of podcasting introduced episodic storytelling in the world of non-fiction sound narrative. Delivering a story in different entries is very different from producing a one-off piece. What concrete implications does this have for the narrative? And what keeps an audience listening to a podcast, episode through episode? This article offers some answers to these questions via a case study of The Habitat, a 2018 podcast by the American network Gimlet.


Relativistic Astronomy. Iii. Test Of Special Relativity Via Doppler Effect, Yuan-Pei Yang, Jin-Peng Zhu, Bing Zhang 2019 Yunnan University

Relativistic Astronomy. Iii. Test Of Special Relativity Via Doppler Effect, Yuan-Pei Yang, Jin-Peng Zhu, Bing Zhang

Physics & Astronomy Faculty Publications

The "Breakthrough Starshot" program is planning to send transrelativistic probes to travel to nearby stellar systems within decades. Because the probe velocity is designed to be a good fraction of the light speed, Zhang & Li recently proposed that these transrelativistic probes can be used to study astronomical objects and to test special relativity. In this work, we propose some methods to test special relativity and constrain photon mass using the Doppler effect with the images and spectral features of astronomical objects as observed in the transrelativistic probes. We introduce more general theories to set up the framework of testing special ...


A Global View Of The Inner Accretion And Ejection Flow Around Super Massive Black Holes, Margherita Giustini, Daniel Proga 2019 Centro de Astrobiologia

A Global View Of The Inner Accretion And Ejection Flow Around Super Massive Black Holes, Margherita Giustini, Daniel Proga

Physics & Astronomy Faculty Publications

Context. Understanding the physics and geometry of accretion and ejection around super massive black holes (SMBHs) is important to understand the evolution of active galactic nuclei (AGN) and therefore of the large scale structures of the Universe. Aims. We aim at providing a simple, coherent, and global view of the sub-parsec accretion and ejection flow in AGN with varying Eddington ratio, ṁ, and black hole mass, MBH. Methods. We made use of theoretical insights, results of numerical simulations, as well as UV and X-ray observations to review the inner regions of AGN by including different accretion and ejection modes, with ...


Polar Alignment Of A Protoplanetary Disc Around An Eccentric Binary – Iii. Effect Of Disc Mass, Rebecca G. Martin, Stephen H. Lubow 2019 University of Nevada, Las Vegas

Polar Alignment Of A Protoplanetary Disc Around An Eccentric Binary – Iii. Effect Of Disc Mass, Rebecca G. Martin, Stephen H. Lubow

Physics & Astronomy Faculty Publications

An initially sufficiently misaligned low-mass protoplanetary disc around an eccentric binary undergoes damped nodal oscillations of tilt angle and longitude of ascending node. Dissipation causes evolution towards a stationary state of polar alignment in which the disc lies perpendicular to the binary orbital plane with angular momentum aligned to the eccentricity vector of the binary. We use hydrodynamic simulations and analytical methods to investigate how the mass of the disc affects this process. The simulations suggest that a disc with non-zero mass settles into a stationary state in the frame of the binary, the generalized polar state, at somewhat lower ...


The Radial Distribution Of Dust Particles In The Hl Tau Disk From Alma And Vla Observations, Carlos Carrasco-Gonzalez, Anibal Sierra, Mario Flock, Zhaohuan Zhu, Thomas Henning, Claire Chandler, Roberto Galvan-Madrid, Enrique Macias, Guillem Anglada, Hendrik Linz, Mayra Osorio, Luis F. Rodriguez, Leonardo Testi, Jose M. Torrelles, Laura Perez, Yao Liu 2019 Universidad Nacional Autonoma de Mexico

The Radial Distribution Of Dust Particles In The Hl Tau Disk From Alma And Vla Observations, Carlos Carrasco-Gonzalez, Anibal Sierra, Mario Flock, Zhaohuan Zhu, Thomas Henning, Claire Chandler, Roberto Galvan-Madrid, Enrique Macias, Guillem Anglada, Hendrik Linz, Mayra Osorio, Luis F. Rodriguez, Leonardo Testi, Jose M. Torrelles, Laura Perez, Yao Liu

Physics & Astronomy Faculty Publications

Understanding planet formation requires one to discern how dust grows in protoplanetary disks. An important parameter to measure in disks is the maximum dust grain size present. This is usually estimated through measurements of the dust opacity at different millimeter wavelengths assuming optically thin emission and dust opacity dominated by absorption. However, Atacama Large Millimeter/submillimeter Array (ALMA) observations have shown that these assumptions might not be correct in the case of protoplanetary disks, leading to overestimation of particle sizes and to underestimation of the disk's mass. Here, we present an analysis of high-quality ALMA and Very Large Array ...


Gamma-Ray Bursts Induced By Turbulent Reconnection, A. Lazarian, Bing Zhang, Siyao Xu 2019 University of Wisconsin

Gamma-Ray Bursts Induced By Turbulent Reconnection, A. Lazarian, Bing Zhang, Siyao Xu

Physics & Astronomy Faculty Publications

We revisit the Internal-Collision-induced MAgnetic Reconnection and Turbulence model of gamma-ray bursts (GRBs) in view of the advances made in understanding of both relativistic magnetic turbulence and relativistic turbulent magnetic reconnection. We identify the kink instability as the most natural way of changing the magnetic configuration to release the magnetic free energy through magnetic reconnection, as well as driving turbulence that enables fast turbulent reconnection. We show that this double role of the kink instability is important for explaining the prompt emission of GRBs. Our study confirms the critical role that turbulence plays in boosting reconnection efficiency in GRBs and ...


Simultaneous In Situ Measurements Of Small-Scale Structures In Neutral, Plasma, And Atomic Oxygen Densities During The Wadis Sounding Rocket Project, Boris Strelnikov, Martin Eberhart, Martin Friedrich, Jonas Hedin, Mikhail Khaplanov, Gerd Baumgarten, Bifford P. Williams, Tristan Staszak, Heiner Asmus, Irina Strelnikova, Ralph Latteck, Mykhaylo Grygalashvyly, Franz-Josef Lübken, Josef Höffner, Raimund Wörl, Jörg Gumbel, Stefan Löhle, Stefanos Fasoulas, Markus Rapp, Aroh Barjatya, Michael J. Taylor, Pierre-Dominique Pautet 2019 Rostock University

Simultaneous In Situ Measurements Of Small-Scale Structures In Neutral, Plasma, And Atomic Oxygen Densities During The Wadis Sounding Rocket Project, Boris Strelnikov, Martin Eberhart, Martin Friedrich, Jonas Hedin, Mikhail Khaplanov, Gerd Baumgarten, Bifford P. Williams, Tristan Staszak, Heiner Asmus, Irina Strelnikova, Ralph Latteck, Mykhaylo Grygalashvyly, Franz-Josef Lübken, Josef Höffner, Raimund Wörl, Jörg Gumbel, Stefan Löhle, Stefanos Fasoulas, Markus Rapp, Aroh Barjatya, Michael J. Taylor, Pierre-Dominique Pautet

Publications

In this paper we present an overview of measurements conducted during the WADIS-2 rocket campaign. We investigate the effect of small-scale processes like gravity waves and turbulence on the distribution of atomic oxygen and other species in the mesosphere–lower thermosphere (MLT) region. Our analysis suggests that density fluctuations of atomic oxygen are coupled to fluctuations of other constituents, i.e., plasma and neutrals. Our measurements show that all measured quantities, including winds, densities, and temperatures, reveal signatures of both waves and turbulence. We show observations of gravity wave saturation and breakdown together with simultaneous measurements of generated turbulence. Atomic ...


A Near Horizon Extreme Binary Black Hole Geometry, Jacob Ciafre, Maria J. Rodriguez 2019 Utah State University

A Near Horizon Extreme Binary Black Hole Geometry, Jacob Ciafre, Maria J. Rodriguez

All Physics Faculty Presentations

A new solution of four-dimensional vacuum General Relativity is presented. It describes the near horizon region of the extreme (maximally spinning) binary black hole system with two identical extreme Kerr black holes held in equilibrium by a massless strut. This is the first example of a non-supersymmetric, near horizon extreme binary black hole geometry of two uncharged black holes. The black holes are co-rotating, their relative distance is fixed, and the solution is uniquely specified by the mass. Asymptotically, the geometry corresponds to the near horizon extreme Kerr (NHEK) black hole. The binary extreme system has finite entropy.


Wallaby Early Science − V. Askap Hi Imaging Of The Lyon Group Of Galaxies 351, B. Q. For, L. Staveley-Smith, T. Westmeier, M. Whiting, S. -H. Oh, B. Koribalski, J. Wang, O. I. Wong, G. Bekiaris, L. Cortese, A. Elagali, D. Kleiner, K. Lee-Waddell, Juan P. Madrid, A. Popping, J. Rhee, T. N. Reynolds, J. D. Collier, C. J. Phillips, M. A. Voronkov, O. Mueller, H. Jerjen 2019 University of Western Australia

Wallaby Early Science − V. Askap Hi Imaging Of The Lyon Group Of Galaxies 351, B. Q. For, L. Staveley-Smith, T. Westmeier, M. Whiting, S. -H. Oh, B. Koribalski, J. Wang, O. I. Wong, G. Bekiaris, L. Cortese, A. Elagali, D. Kleiner, K. Lee-Waddell, Juan P. Madrid, A. Popping, J. Rhee, T. N. Reynolds, J. D. Collier, C. J. Phillips, M. A. Voronkov, O. Mueller, H. Jerjen

Physics and Astronomy Faculty Publications and Presentations

We present an HI study of the galaxy group LGG 351 usingWidefield ASKAP L-band Legacy All-sky Blind Survey (WALLABY) early science data observed with the Australian Square Kilometre Array Pathfinder (ASKAP). LGG 351 resides behind the M 83 group at a velocity range (cz) of ∼3500–4800 km s−1 within the rich Hydra-Centaurus overdensity region. We detect 40 sources with the discovery of a tidally interacting galaxy pair and two new HI sources that are not presented in previous optical catalogues. 23 out of 40 sources have new redshifts derived from the new HI data. This study is the ...


Photoionization Calculations Of The Radiation Force Due To Spectral Lines In Agns, Randall C. Dannen, Daniel Proga, Timothy R. Kallman, Tim Waters 2019 University of Nevada, Las Vegas

Photoionization Calculations Of The Radiation Force Due To Spectral Lines In Agns, Randall C. Dannen, Daniel Proga, Timothy R. Kallman, Tim Waters

Physics & Astronomy Faculty Publications

One of the main mechanisms that could drive mass outflows in active galactic nuclei (AGNs) is radiation pressure due to spectral lines. Although straightforward to understand, the actual magnitude of the radiation force is challenging to compute because the force depends on the physical conditions in the gas, as well as the strength, spectral energy distribution (SED), and geometry of the radiation field. We present results from our photoionization and radiation transfer calculations of the force multiplier, M(ξ, t), using the same radiation field to compute the gas photoionization and thermal balance. We assume low gas density (n = 104 ...


Large‐Amplitude Mountain Waves In The Mesosphere Observed On 21 June 2014 During Deepwave: 1.Wave Development, Scales, Momentum Fluxes, And Environmental Sensitivity, Michael J. Taylor, Pierre-Dominique Pautet, David C. Fritts, Bernd Kaifler, Steven M. Smith, Yucheng Zhao, Neal R. Criddle, Pattilyn McLaughlin, William R. Pendleton Jr., Michael P. McCarthy, Gonzalo Hernandez, Stephen D. Eckermann, James Doyle, Markus Rapp, Ben Liley, James M. Russell III 2019 Utah State University

Large‐Amplitude Mountain Waves In The Mesosphere Observed On 21 June 2014 During Deepwave: 1.Wave Development, Scales, Momentum Fluxes, And Environmental Sensitivity, Michael J. Taylor, Pierre-Dominique Pautet, David C. Fritts, Bernd Kaifler, Steven M. Smith, Yucheng Zhao, Neal R. Criddle, Pattilyn Mclaughlin, William R. Pendleton Jr., Michael P. Mccarthy, Gonzalo Hernandez, Stephen D. Eckermann, James Doyle, Markus Rapp, Ben Liley, James M. Russell Iii

Publications

A remarkable, large‐amplitude, mountain wave (MW) breaking event was observed on the night of 21 June 2014 by ground‐based optical instruments operated on the New Zealand South Island during the Deep Propagating Gravity Wave Experiment (DEEPWAVE). Concurrent measurements of the MW structures, amplitudes, and background environment were made using an Advanced Mesospheric Temperature Mapper, a Rayleigh Lidar, an All‐Sky Imager, and a Fabry‐Perot Interferometer. The MW event was observed primarily in the OH airglow emission layer at an altitude of ~82 km, over an ~2‐hr interval (~10:30–12:30 UT), during strong eastward winds ...


"Collaborative Research: Cedar--Airglow Imaging Of Gravity Wave And Instability Dynamics,", Michael Taylor 2019 Utah State University

"Collaborative Research: Cedar--Airglow Imaging Of Gravity Wave And Instability Dynamics,", Michael Taylor

Funded Research Records

No abstract provided.


Searching For Trends In Atmospheric Compositions Of Extrasolar Planets, Kassandra Weber, Paola Rodriguez Hidalgo, Adam Turk, Troy Maloney, Stephen Kane 2019 Humboldt State University

Searching For Trends In Atmospheric Compositions Of Extrasolar Planets, Kassandra Weber, Paola Rodriguez Hidalgo, Adam Turk, Troy Maloney, Stephen Kane

IdeaFest: Interdisciplinary Journal of Creative Works and Research from Humboldt State University

No abstract provided.


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