Relation Between Gravitational Mass And Baryonic Mass For Non-Rotating And Rapidly Rotating Neutron Stars,
2020
Beijing Normal University
Relation Between Gravitational Mass And Baryonic Mass For Non-Rotating And Rapidly Rotating Neutron Stars, He Gao, Shun-Ke Ai, Zhou-Jian Cao, Bing Zhang, Zhen-Yu Zhu, Ang Li, Nai-Bo Zhang, Andreas Bauswein
Physics & Astronomy Faculty Research
With a selected sample of neutron star (NS) equations of state (EOSs) that are consistent with the current observations and have a range of maximum masses, we investigate the relations between NS gravitational mass Mg and baryonic mass Mb, and the relations between the maximum NS mass supported through uniform rotation (Mmax) and that of nonrotating NSs (MTOV). We find that for an EOS-independent quadratic, universal transformation formula (Mb=Mg+A×M2g)(Mb=Mg+A×Mg2), the best-fit A value is 0.080 for non-rotating NSs, 0.064 for maximally rotating NSs, and 0.073 when NSs with arbitrary rotation are considered. The residual error of the transformation is ∼ …
Vla Imaging Of H I-Bearing Ultra-Diffuse Galaxies From The Alfalfa Survey,
2020
Valparaiso University
Vla Imaging Of H I-Bearing Ultra-Diffuse Galaxies From The Alfalfa Survey, Lexi Gault, Lukas Leisman, Elizabeth A.K. Adams, Pavel E. Mancera Piña, Kameron Reiter, Nicholas Smith, Michael Battipaglia, John M. Cannon, Filippo Fraternali, Martha P. Haynes, Elizabeth Mcallan, Hannah J. Pagel, Katherine L. Rhode, John J. Salzer, Quinton Singer
Physics and Astronomy Faculty Publications
Ultra-diffuse galaxies have generated significant interest due to their large optical extents and low optical surface brightnesses, which challenge galaxy formation models. Here we present resolved synthesis observations of 12 H i-bearing ultra-diffuse galaxies (HUDs) from the Karl G. Jansky Very Large Array (VLA), as well as deep optical imaging from the WIYN 3.5-meter telescope at Kitt Peak National Observatory. We present the data processing and images, including total intensity H i maps and H i velocity fields. The HUDs show ordered gas distributions and evidence of rotation, important prerequisites for the detailed kinematic models in Mancera Pi˜na et al. …
A 3-Year Sample Of Almost 1,600 Elves Recorded Above
South America By The Pierre Auger Cosmic-Ray
Observatory,
2020
Radboud University Nijmegen
A 3-Year Sample Of Almost 1,600 Elves Recorded Above South America By The Pierre Auger Cosmic-Ray Observatory, A. Aab, R. Engel, Gregory Snow, Pierre Auger Cosmic-Ray Observatory, 390 Co-Authors
Gregory Snow Publications
Elves are a class of transient luminous events, with a radial extent typically greater than 250 km, that occur in the lower ionosphere above strong electrical storms.We report the observation of 1,598 elves, from 2014 to 2016, recorded with unprecedented time resolution (100 ns) using the fluorescence detector (FD) of the Pierre Auger Cosmic-Ray Observatory. The Auger Observatory is located in the Mendoza province of Argentina with a viewing footprint for elve observations of 3 · 106 km2, reaching areas above the Pacific and Atlantic Oceans, as well as the Córdoba region, which is known for severe convective thunderstorms. Primarily …
Reflection And Reverberation In Neutron Star Low-Mass X-Ray Binaries,
2020
Wayne State University
Reflection And Reverberation In Neutron Star Low-Mass X-Ray Binaries, Benjamin Coughenour
Wayne State University Dissertations
Neutron star low-mass X-ray binaries (NS LMXBs) are systems which consist of a NS and a low-mass companion star. They are naturally variable on a variety of timescales, and are even classified by their X-ray spectral variability on the timescales of hours to days. The most luminous NS LMXB sources are known as ‘Z’ sources, because they trace out a characteristic ‘Z’ shape when plotted on a color-color or hardness-intensity diagram. The physical mechanisms causing this variability are not well understood. To try to address this, we model spectra taken from different positions on a hardness-intensity diagram of two Z …
A Spectropolarimetric Study Of Southern Wr + O Binaries,
2020
University of Denver
A Spectropolarimetric Study Of Southern Wr + O Binaries, Andrew G. Fullard
Electronic Theses and Dissertations
The classical Wolf-Rayet (WR) state is the evolved stage of a massive star, post main-sequence. They are characterized by their strong emission line spectra and stellar winds that are often more than 10 times denser than that of their progenitor O-type stars, which have mass loss rates of 10-6 MΘyr-1. The evolution of WR stars and their connection to specific types of supernovae (SNe) is an open question. Current theory suggests that rapidly rotating massive stars may be the progenitors of SNe that produce long-duration gamma-ray bursts. The interaction between WR stars and their companion …
Using Mesa To Test Our Theory Of Contact Binary Star Evolution,
2020
Calvin University
Using Mesa To Test Our Theory Of Contact Binary Star Evolution, Lauren Henderson, Anneke Avery, Gia Mien Le, Larry A. Molnar
Summer Research
A contact binary star system consists of two stars orbiting each other so closely that they share a common atmosphere (Figure 1). Nearly 1% of stars like our sun are contact binaries, yet there is not a comprehensive model of their lives. Our goal is to understand the formation, life, and explosive demise of these objects. This summer we used MESA, a stellar modeling program, paired with a Python program to model the lives of contact binary stars.
Full Orbital Solution For The Binary System In The Northern Galactic Disc Microlensing Event Gaia16aye,
2020
Swarthmore College
Full Orbital Solution For The Binary System In The Northern Galactic Disc Microlensing Event Gaia16aye, Ł. Wyrzykowski, P. Mróz, K. A. Rybicki, M. Gromadzki, Z. Kołaczkowski, M. Zieliński, P. Zieliński, N. Britavskiy, A. Gomboc, K. Sokolovsky, S. T. Hodgkin, L. Abe, G. F. Aldi, A. Almannaei, G. Altavilla, A. Al Qasim, G. C. Anupama, S. Awiphan, E. Bachelet, V. Bakış, S. Baker, S. Bartlett, P. Bendjoya, K. Benson, I. F. Bikmaev, G. Birenbaum, N. Blagorodnova, S. Blanco-Cuaresma, S. Boeva, A. Z. Bonanos, V. Bozza, D. M. Bramich, I. Bruni, R. A. Burenin, U. Burgaz, T. Butterley, H. E. Caines, D. B. Caton, S. Calchi Novati, J. M. Carrasco, A. Cassan, V. Čepas, M. Cropper, M. Chruślińska, G. Clementini, A. Clerici, D. Conti, M. Conti, S. Cross, F. Cusano, G. Damljanovic, D. Dapergolas, G. D'Ago, J. H. J. De Bruijne, M. Dennefeld, V. S. Dhillon, M. Dominik, J. Dziedzic, O. Erece, M. V. Eselevich, H. Esenoglu, L. Eyer, R. Figuera Jaimes, S. J. Fossey, A. I. Galeev, S. A. Grebenev, A. C. Gupta, A. G. Gutaev, N. Hallakoun, A. Hamanowicz, C. Han, B. Hanzlik, J. B. Haislip, L. Hanlon, L. K. Hardy, D. L. Harrison, H. J. Van Heerden, V. L. Hoette, K. Horne, R. Hudec, M. Hundertmark, N. Ihanec, E. N. Irtuganov, R. Itoh, P. Iwanek, M. D. Jovanovic, R. Janulis, M. Jelínek, Eric L.N. Jensen, Z. Kaczmarek, D. Katz, I. M. Khamitov, Y. Kilic, J. Klencki, U. Kolb, G. Kopacki, V. V. Kouprianov, K. Kruszyńska, S. Kurowski, G. Latev, C.-H. Lee, S. Leonini, G. Leto, F. Lewis, Z. Li, A. Liakos, S. P. Littlefair, J. Lu, C. J. Manser, S. Mao, D. Maoz, A. Martin-Carrillo, J. P. Marais, M. Maskoliūnas, J. R. Maund, P. J. Meintjes, S. S. Melnikov, K. Ment, P. Mikołajczyk, M. Morrell, N. Mowlavi, D. Moździerski, D. Murphy, S. Nazarov, H. Netzel, R. Nesci, C.-C. Ngeow, A. J. Norton, E. O. Ofek, E. Pakštienė, L. Palaversa, A. Pandey, E. Paraskeva, M. Pawlek, M. T. Penny, B. E. Penprase, A. Piascik, J. L. Prieto, J. K. T. Qvam, C. Ranc, A. Rebassa-Mansergas, D. E. Reichert, P. Reig, L. Rhodes, J.-P. Rivet, G. Rixon, D. Roberts, P. Rosi, D. M. Russell, R. Zanmar Sanchez, G. Scarpetta, G. Seabroke, B. J. Shappee, R. Schmidt, Y. Shvartzvald, M. Sitek, J. Skowron, M. Śniegowska, C. Snodgrass, P. S. Soares, B. Van Soelen, Z. T. Spetsieri, A. Stankevičiūtė, I. A. Steele, R. A. Street, J. Strobl, E. Strubble, H. Szegedi, L. M. Tinjava Ramirez, L. Tomasella, Y. Tsapras, D. Vernet, S. Villanueva Jr., O. Vince, J. Wambsganss, I. P. Van Der Westhuizen, K. Wiersema, D. Wium, R. W. Wilson, A. Yoldas, R. Ya. Zhuchkov, D. G. Zhukov, J. Zdanavičius, S. Zoła, A. Zubareva
Physics & Astronomy Faculty Works
Gaia16aye was a binary microlensing event discovered in the direction towards the northern Galactic disc and was one of the first microlensing events detected and alerted to by the Gaia space mission. Its light curve exhibited five distinct brightening episodes, reaching up to I = 12 mag, and it was covered in great detail with almost 25 000 data points gathered by a network of telescopes. We present the photometric and spectroscopic follow-up covering 500 days of the event evolution. We employed a full Keplerian binary orbit microlensing model combined with the motion of Earth and Gaia around the Sun …
Hd 213885b: A Transiting 1-D-Period Super-Earth With An Earth-Like Composition Around A Bright (V = 7.9) Star Unveiled By Tess,
2020
Swarthmore College
Hd 213885b: A Transiting 1-D-Period Super-Earth With An Earth-Like Composition Around A Bright (V = 7.9) Star Unveiled By Tess, N. Espinoza, R. Brahm, T. Henning, A. Jordán, C. Dorn, F. Rojas, P. Sarkis, D. Kossakowski, M. Schlecker, M. R. Díaz, J. S. Jenkins, C. Aguilera-Gomez, J. M. Jenkins, J. D. Twicken, K. A. Collins, J. Lissauer, D. J. M. Armstrong, V. Adibekyan, D. Barrado, S. C. C. Barros, M. Battley, D. Bayliss, F. Bouchy, E. M. Bryant, B. F. Cooke, O. D. S. Demaneon, X. Dumusque, P. Figueira, H. Giles, J. Lillo-Box, C. Lovis, L. D. Nielsen, F. Pepe, D. Pollacco, N. C. Santos, S. G. Sousa, S. Udry, P. J. Wheatley, O. Turner, M. Marmier, D, Ségransan, G. Ricker, D. Latham, S. Seager, J. N. Winn, J. F. Kielkopf, R. Hart, G. Wingham, Eric L.N. Jensen, K. G. Hełminiak, A. Tokovinin, C. Briceño, C. Ziegler, N. M. Law, A. W. Mann, T. Daylan, J. P. Doty, N. Guerrero, P. Boyd, I. Crossfield, R. I. Morris, C. E. Henze, A. D. Chacon
Physics & Astronomy Faculty Works
We report the discovery of the 1.008-d, ultrashort period (USP) super-Earth HD 213885b (TOI-141b) orbiting the bright (V = 7.9) star HD 213885 (TOI-141, TIC 403224672), detected using photometry from the recently launched TESS mission. Using FEROS, HARPS, and CORALIE radial velocities, we measure a precise mass of 8.8 ± 0.6 M⊕ for this 1.74 ± 0.05 R⊕ exoplanet, which provides enough information to constrain its bulk composition – similar to Earth’s but enriched in iron. The radius, mass, and stellar irradiation of HD 213885b are, given our data, very similar to 55 Cancri e, making this exoplanet a good …
Lambert W Function Methods In Double Square Well And Waveguide Problems,
2020
University of Western Ontario
Lambert W Function Methods In Double Square Well And Waveguide Problems, Narola Harsh Bharatbhai, P C Deshmukh, Robert B. Scott, Ken Roberts, Sree Ram Valluri
Physics and Astronomy Publications
Using methods related to the Lambert W function, we present solutions of two apparently different problems: (1) The one-dimensional double square well potential in quantum mechanics and (2) The transverse electric and magnetic modes for a step-index electromagnetic waveguide. The solution techniques provide insight into the bound energy states for the single and double square well problems and the allowed modes of propagation in a waveguide with varying refractive indices. The solutions can be viewed in either of two related complex plane representations. Comparison of the solution geometries suggests that interesting applications may be possible in nanostructures and devices which …
A Numerical Approach To Modeling Submoons And Investigating Stability Regions,
2020
Rollins College
A Numerical Approach To Modeling Submoons And Investigating Stability Regions, Josephine Spiegelberg
Honors Program Theses
The recent discovery of the Neptune-sized exomoon candidate Kepler-1625bi (Teachey et al. 2018) has prompted a wave of research into the possibility of such a large satellite hosting its own moons, or submoons. These submoons have a lot in common with moons, and lessons from moon stability calculations can help to understand submoon behavior and stability. Past submoon research has focused on determining stability regions for these submoons using simplified models of the body’s tidal evolution (Reid 1973, Conrad 1985, Kollmeier and Raymond 2019). In order to provide a more detailed understanding of submoon behavior, a Fortran N-Body code was …
Creating A Sample Of Off-Color Galaxies Using Big Data Tools,
2020
Rollins College
Creating A Sample Of Off-Color Galaxies Using Big Data Tools, Christopher Becker
Honors Program Theses
This thesis begins an investigation into the presence of off-colored galaxies in the Sloan Digital Sky Survey. Through establishing the emergence and history of Astroinformatics, the thesis introduces the concepts surrounding both off-color galaxies and the Big Data tools helpful in analyzing the data to find them. A discussion of initial implementation methods and revised implementation due to difficulties with previous plans follows. Results are presented, with well in excess of 500,000 candidates for off-color galaxies present in the sample. Conclusions are then drawn regarding such a large sample and the implications this may have on the conventional understanding of …
The Large Millimeter Telescope (Lmt) Alfonso Serrano: Current Status And Telescope Performance,
2020
Instituto Nacional de Astrofisica Optica y Electronica
The Large Millimeter Telescope (Lmt) Alfonso Serrano: Current Status And Telescope Performance, David H. Hughes, F. Peter Schloerb, Itziar Aretxaga, Edgar Castillo-Domínguez, Miguel Chávez Dagostino, Edgar Colín, Neal Erickson, Daniel Ferrusca Rodriguez, David M. Gale, Arturo Gómez-Ruiz, José Luis Hernández Rebollar, Mark Heyer, James Lowenthal, Alfredo Montaña, Marcos Emir Moreno Nolasco, Gopal Narayanan, Alexandra Pope, Iván Rodríguez-Montoya, David Sánchez-Argüelles, David Smith, Kamal Souccar, Miguel Velázquez De La Rosa Becerra, Grant W. Wilson, Min S. Yun
Astronomy: Faculty Publications
The Large Millimeter Telescope (LMT) Alfonso Serrano is a 50m-diameter single-dish radio telescope constructed at an altitude of 4600 meters on the summit of Volcan Sierra Negra, an extinct volcano in the Mexican state of Puebla. The LMT is a bi-national scientific collaboration between Mexico and the USA, led by the Instituto Nacional de Astrofisica, Optica y Electronica (INAOE) and the University of Massachusetts at Amherst. The telescope currently operates at wavelengths from 4mm to 1mm, and during the dry winter months the LMT site provides the highest levels of atmospheric transmission and potential future access to submillimeter observing windows. …
First Resolved Scattered-Light Images Of Four Debris Disks In Scorpius-Centaurus With The Gemini Planet Imager,
2020
School of Earth and Space Exploration
First Resolved Scattered-Light Images Of Four Debris Disks In Scorpius-Centaurus With The Gemini Planet Imager, Justin Hom, Jennifer Patience, Thomas M. Esposito, Gaspard Duchene, Kadin Worthen, Paul Kalas, Hannah Jang-Condell, Kezman Saboi, Pauline Arriaga, Johan Mazoyer, Schuyler Wolff, Maxwell A. Millar-Blanchaer, Michael P. Fitzgerald, Marshall D. Perrin, Christine H. Chen, Bruce Macintosh, Brenda C. Matthews, Jason J. Wang, James R. Graham, Franck Marchis, S. Mark Ammons, Vanessa P. Bailey, Travis Barman, Joanna Bulger, Jeffrey K. Chilcote, Tara Cotten, Robert J. De Rosa, René Doyon, Katherine B. Follette, Steven Goodsell, Alexandra Z. Greenbaum, Pascale Hibon, Kimberly Ward-Duong, Et Al
Astronomy: Faculty Publications
We present the first spatially resolved scattered-light images of four debris disks around members of the Scorpius-Centaurus (Sco-Cen) OB association with high-contrast imaging and polarimetry using the Gemini Planet Imager (GPI). All four disks are resolved for the first time in polarized light, and one disk is also detected in total intensity. The three disks imaged around HD 111161, HD 143675, and HD 145560 are symmetric in both morphology and brightness distribution. The three systems span a range of inclinations and radial extents. The disk imaged around HD 98363 shows indications of asymmetries in morphology and brightness distribution, with some …
An Updated Visual Orbit Of The Directly Imaged Exoplanet 51 Eridani B And Prospects For A Dynamical Mass Measurement With Gaia,
2020
Stanford University
An Updated Visual Orbit Of The Directly Imaged Exoplanet 51 Eridani B And Prospects For A Dynamical Mass Measurement With Gaia, Robert J. De Rosa, Eric L. Nielsen, Jason J. Wang, S. Mark Ammons, Gaspard Duchene, Bruce Macintosh, Julien Rameau, Vanessa P. Bailey, Travis Barman, Joanna Bulger, Jeffrey Chilcote, Tara Cotten, Rene Doyon, Thomas M. Esposito, Michael P. Fitzgerald, Katherine B. Follette, Benjamin L. Gerard, Stephen J. Goodsell, James R. Graham, Alexandra Z. Greenbaum, Pascale Hibon, Justin Hom, Li Wei Hung, Patrick Ingraham, Paul Kalas, Quinn Konopacky, James E. Larkin, Jérôme Maire, Franck Marchis, Mark S. Marley, Christian Marois, Stanimir Metchev, Kimberly Ward-Duong, Et Al
Astronomy: Faculty Publications
We present a revision to the visual orbit of the young, directly imaged exoplanet 51 Eridani b using four years of observations with the Gemini Planet Imager. The relative astrometry is consistent with an eccentric (e= 0.53-0.13+0.09) orbit at an intermediate inclination (i= 13611+10°), although circular orbits cannot be excluded due to the complex shape of the multidimensional posterior distribution. We find a semimajor axis of 11.1-1.3+4.2 au and a period of 28.1-4.9+17.2 yr, assuming a mass of 1.75 M· for the host star. We find consistent values with a recent analysis of VLT/SPHERE data covering a similar baseline. We …
Characterizing The Quantum Phase Transition Using A Flat Band In Circuit Qed Lattices,
2020
The University of Texas Rio Grande Valley
Characterizing The Quantum Phase Transition Using A Flat Band In Circuit Qed Lattices, Gui-Lei Zhu, Xin-You Lü, Hamidreza Ramezani
Physics & Astronomy Faculty Publications
We show the superradiant phase transition (SPT) can control the existence of flat band in an extended Dicke-Hubbard lattice [1]
The Exogravity Project: Using Single Mode Interferometry To Characterize Exoplanets,
2020
Sorbonne Université
The Exogravity Project: Using Single Mode Interferometry To Characterize Exoplanets, S. Lacour, J. J. Wang, M. Nowak, L. Pueyo, F. Eisenhauer, A. M. Lagrange, P. Mollière, R. Abuter, A. Amorin, R. Asensio-Torres, M. Bauböck, M. Benisty, J. P. Berger, H. Beust, S. Blunt, A. Boccaletti, A. Bohn, M. Bonnefoy, H. Bonnet, W. Brandner, F. Cantalloube, P. Caselli, B. Charnay, G. Chauvin, E. Choquet, V. Christiaens, Y. Clénet, A. Cridland, P. T. De Zeeuw, R. Dembet, J. Dexter, A. Drescher, Kimberly Ward-Duong, Et Al
Astronomy: Faculty Publications
Combining adaptive optics and interferometric observations results in a considerable contrast gain compared to single-telescope, extreme AO systems. Taking advantage of this, the ExoGRAVITY project is a survey of known young giant exoplanets located in the range of 0.1"to 2"from their stars. The observations provide astrometric data of unprecedented accuracy, being crucial for refining the orbital parameters of planets and illuminating their dynamical histories. Furthermore, GRAVITY will measure non-Keplerian perturbations due to planet-planet interactions in multi-planet systems and measure dynamical masses. Over time, repetitive observations of the exoplanets at medium resolution (R = 500) will provide a catalogue of K-band …
Revised Astrometric Calibration Of The Gemini Planet Imager,
2020
European Southern Observatory Santiago
Revised Astrometric Calibration Of The Gemini Planet Imager, Robert J. De Rosa, Meiji M. Nguyen, Jeffrey Chilcote, Bruce Macintosh, Marshall D. Perrin, Quinn Konopacky, Jason J. Wang, Gaspard Duchêne, Eric L. Nielsen, Julien Rameau, S. Mark Ammons, Vanessa P. Bailey, Travis Barman, Joanna Bulger, Tara Cotten, Rene Doyon, Thomas M. Esposito, Michael P. Fitzgerald, Katherine B. Follette, Benjamin L. Gerard, Stephen J. Goodsell, James R. Graham, Alexandra Z. Greenbaum, Pascale Hibon, Li Wei Hung, Patrick Ingraham, Paul Kalas, James E. Larkin, Jérôme Maire, Franck Marchis, Mark S. Marley, Christian Marois, Kimberly Ward-Duong, Et Al
Astronomy: Faculty Publications
We present a revision to the astrometric calibration of the Gemini Planet Imager (GPI), an instrument designed to achieve the high contrast at small angular separations necessary to image substellar and planetary-mass companions around nearby, young stars. We identified several issues with the GPI data reduction pipeline (DRP) that significantly affected the determination of the angle of north in reduced GPI images. As well as introducing a small error in position angle measurements for targets observed at small zenith distances, this error led to a significant error in the previous astrometric calibration that has affected all subsequent astrometric measurements. We …
Hunting For Ultra Diffuse Galaxies In The Hubble Space Telescope Data Archive,
2020
University of Alabama in Huntsville
Hunting For Ultra Diffuse Galaxies In The Hubble Space Telescope Data Archive, Nicholas Schragal
Summer Community of Scholars Posters (RCEU and HCR Combined Programs)
No abstract provided.
On Entropy Conservation And Kinetic Energy
Preservation Methods,
2020
NASA Ames Research Center
On Entropy Conservation And Kinetic Energy Preservation Methods, H. C. Yee, Björn Sjögreen
United States National Aeronautics and Space Administration: Publications
The Tadmor-type entropy conservative method using the mathematical logarithmic entropy function and two forms of the Sjögreen & Yee entropy conservative methods using the Harten entropy function are examined for their nonlinear stability and accuracy in very long time integration of the Euler equations of compressible gas dynamics. Following the same procedure as Ranocha [6] these entropy conservative methods can be made kinetic energy preserving with minimum added computational effort. The focus of this work is to examine the nonlinear stability and accuracy of these newly introduced high order entropy conserving and kinetic energy preserving methods for very long time …
There Is No Constant In Physics: A Neutrosophic Explanation,
2020
University of New Mexico
There Is No Constant In Physics: A Neutrosophic Explanation, Victor Christianto, Robert Neil Boyd, Florentin Smarandache
Branch Mathematics and Statistics Faculty and Staff Publications
In Neutrosophic Logic, a basic assertion is that there are variations of about everything that we can measure; the variations surround three parameters called T,I,F (truth, indeterminacy, falsehood) which can take a range of values. Similarly, in this paper we consider NL applications in physics constants. Those constants actually all have a window of plus and minus values, relative to the average value of the constant. For example, speed of light, c, can vary in a window up to +/- 3000 m/s. Therefore it should be written: 300000 km/s +/- 3 km/s. We also discuss some implications of this new …
