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Gw190425: Observation Of A Compact Binary Coalescence With Total Mass ∼ 3.4 M O, B. P. Abbott, R. Abbott, T. D. Abbott, S. Abraham, F. Acernese, K. Ackley, C. Adams, R. X. Adhikari, V. B. Adya, C. Affeldt, M. Agathos, K. Agatsuma, N. Aggarwal, O. D. Aguiar, L. Aiello, A. Ain, P. Ajith, G. Allen, A. Allocca, M. A. Aloy, P. A. Altin, A. Amato, S. Anand, A. Ananyeva, S. B. Anderson, W. G. Anderson, S. V. Angelova, S. Antier, S. Appert, K. Arai, M. C. Araya, Tiffany Z. Summerscales 2020 California Institute of Technology

Gw190425: Observation Of A Compact Binary Coalescence With Total Mass ∼ 3.4 M O, B. P. Abbott, R. Abbott, T. D. Abbott, S. Abraham, F. Acernese, K. Ackley, C. Adams, R. X. Adhikari, V. B. Adya, C. Affeldt, M. Agathos, K. Agatsuma, N. Aggarwal, O. D. Aguiar, L. Aiello, A. Ain, P. Ajith, G. Allen, A. Allocca, M. A. Aloy, P. A. Altin, A. Amato, S. Anand, A. Ananyeva, S. B. Anderson, W. G. Anderson, S. V. Angelova, S. Antier, S. Appert, K. Arai, M. C. Araya, Tiffany Z. Summerscales

Faculty Publications

© 2020. The Author(s). Published by the American Astronomical Society.. On 2019 April 25, the LIGO Livingston detector observed a compact binary coalescence with signal-to-noise ratio 12.9. The Virgo detector was also taking data that did not contribute to detection due to a low signal-to-noise ratio, but were used for subsequent parameter estimation. The 90% credible intervals for the component masses range from to if we restrict the dimensionless component spin magnitudes to be smaller than 0.05). These mass parameters are consistent with the individual binary components being neutron stars. However, both the source-frame chirp mass and the total mass …


Gw190425: Observation Of A Compact Binary Coalescence With Total Mass ∼ 3.4 M⊙, B. P. Abbott, R. Abbott, T. D. Abbott, Teviet Creighton, Mario C. Diaz, Soma Mukherjee, Volker Quetschke, Malik Rakhmanov, Satzhan Sitmukhambetov, Wenhui Wang 2020 The University of Texas Rio Grande Valley

Gw190425: Observation Of A Compact Binary Coalescence With Total Mass ∼ 3.4 M⊙, B. P. Abbott, R. Abbott, T. D. Abbott, Teviet Creighton, Mario C. Diaz, Soma Mukherjee, Volker Quetschke, Malik Rakhmanov, Satzhan Sitmukhambetov, Wenhui Wang

Physics & Astronomy Faculty Publications

On 2019 April 25, the LIGO Livingston detector observed a compact binary coalescence with signal-to-noise ratio 12.9. The Virgo detector was also taking data that did not contribute to detection due to a low signal-to-noise ratio, but were used for subsequent parameter estimation. The 90% credible intervals for the component masses range from to (– if we restrict the dimensionless component spin magnitudes to be smaller than 0.05). These mass parameters are consistent with the individual binary components being neutron stars. However, both the source-frame chirp mass and the total mass of this system are significantly larger than those of …


Loop-Closure Kinetics Reveal A Stable, Right-Handed Dna Intermediate In Cre Recombination, Massa J. Shoura, Stefan M. Giovan, Alexandre A. Vetcher, Riccardo Ziraldo, Andreas Hanke, Stephen D. Levene 2020 The University of Texas Rio Grande Valley

Loop-Closure Kinetics Reveal A Stable, Right-Handed Dna Intermediate In Cre Recombination, Massa J. Shoura, Stefan M. Giovan, Alexandre A. Vetcher, Riccardo Ziraldo, Andreas Hanke, Stephen D. Levene

Physics & Astronomy Faculty Publications

In Cre site-specific recombination, the synaptic intermediate is a recombinase homotetramer containing a pair of loxP DNA target sites. The enzyme system's strand-exchange mechanism proceeds via a Holliday-junction (HJ) intermediate; however, the geometry of DNA segments in the synapse has remained highly controversial. In particular, all crystallographic structures are consistent with an achiral, planar Holliday-junction (HJ) structure, whereas topological assays based on Cre-mediated knotting of plasmid DNAs are consistent with a right-handed chiral junction. We use the kinetics of loop closure involving closely spaced (131–151 bp) loxP sites to investigate the in-aqueo ensemble of conformations for the longest-lived looped DNA …


On The Frb Luminosity Function – – Ii. Event Rate Density, Rui Luo, Yunpeng Men, Kejia Lee, Weiyang Wang, D. R. Lorimer, Bing Zhang 2020 Peking University

On The Frb Luminosity Function – – Ii. Event Rate Density, Rui Luo, Yunpeng Men, Kejia Lee, Weiyang Wang, D. R. Lorimer, Bing Zhang

Physics & Astronomy Faculty Research

The luminosity function of Fast Radio Bursts (FRBs), defined as the event rate per unit cosmic co-moving volume per unit luminosity, may help to reveal the possible origins of FRBs and design the optimal searching strategy. With the Bayesian modelling, we measure the FRB luminosity function using 46 known FRBs. Our Bayesian framework self-consistently models the selection effects, including the survey sensitivity, the telescope beam response, and the electron distributions from Milky Way/ the host galaxy/ local environment of FRBs. Different from the previous companion paper, we pay attention to the FRB event rate density and model the event counts …


Testing The Hypothesis Of Compact-Binary-Coalescence Origin Of Fast Radio Bursts Using A Multimessenger Approach, Min-Hao Wang, Shun-Ke Ai, Zheng-Xiang Li, Nan Xing, He Gao, Bing Zhang 2020 Beijing Normal University

Testing The Hypothesis Of Compact-Binary-Coalescence Origin Of Fast Radio Bursts Using A Multimessenger Approach, Min-Hao Wang, Shun-Ke Ai, Zheng-Xiang Li, Nan Xing, He Gao, Bing Zhang

Physics & Astronomy Faculty Research

In the literature, compact binary coalescences (CBCs) have been proposed as one of the main scenarios to explain the origin of some non-repeating fast radio bursts (FRBs). The large discrepancy between the FRB and CBC event rate densities suggests that their associations, if any, should only apply at most for a small fraction of FRBs. Through a Bayesian estimation method, we show how a statistical analysis of the coincident associations of FRBs with CBC gravitational wave (GW) events may test the hypothesis of these associations. We show that during the operation period of the advanced Laser Interferometer Gravitational-Wave Observatory (aLIGO), …


A Comprehensive Catalog Of Dark Matter Halo Models For Sparc Galaxies, Pengfei Li, Stacy S. McGaugh 2020 Case Western Reserve University

A Comprehensive Catalog Of Dark Matter Halo Models For Sparc Galaxies, Pengfei Li, Stacy S. Mcgaugh

Faculty Scholarship

We present rotation curve fits to 175 late-type galaxies from the Spitzer Photometry and Accurate Rotation Curves database using seven dark matter (DM) halo profiles: pseudo-isothermal, Burkert, Navarro-Frenk-White (NFW), Einasto, Di Cintio et al. (2014, hereafter DC14), cored-NFW, and a new semi-empirical profile named Lucky13. We marginalize over the stellar mass-to-light ratio, galaxy distance, disk inclination, halo concentration, and halo mass (and an additional shape parameter for Einasto) using a Markov Chain Monte Carlo method. We find that cored halo models, such as the DC14 and Burkert profiles, generally provide better fits to rotation curves than the cuspy NFW profile. …


Sun-Like Stars Shed Light On Solar Climate Forcing, Philip G. Judge, Ricky Egeland, Gregory W. Henry 2020 National Center for Atmospheric Research

Sun-Like Stars Shed Light On Solar Climate Forcing, Philip G. Judge, Ricky Egeland, Gregory W. Henry

Information Systems and Engineering Management Research Publications

Recently published precise stellar photometry of 72 Sun-like stars obtained at the Fairborn Observatory between 1993 and 2017 is used to set limits on the solar forcing of Earth's atmosphere of ±4.5 W m−2 since 1750. This compares with the +2.2 ± 1.1 W m−2 IPCC estimate for anthropogenic forcing. Three critical assumptions are made. In decreasing order of importance they are: (a) most of the brightness variations occur within the average time series length of ≈17 yr; (b) the Sun seen from the ecliptic behaves as an ensemble of middle-aged solar-like stars; and (c) narrowband photometry in the Strömgren …


Discovery Of A Remarkably Powerful Broad Absorption-Line Quasar Outflow In Sdss J135246.37+423923.5, Hyunseop Choi, Karen M. Leighly, Donald M. Terndrup, Sarah C. Gallagher, Gordon T. Richards 2020 University of Oklahoma

Discovery Of A Remarkably Powerful Broad Absorption-Line Quasar Outflow In Sdss J135246.37+423923.5, Hyunseop Choi, Karen M. Leighly, Donald M. Terndrup, Sarah C. Gallagher, Gordon T. Richards

Physics and Astronomy Publications

Broad absorption-line (BAL) features in quasar spectra reveal an unambiguous signature of energetic outflows from central supermassive black holes, and thus, BAL quasars are prime targets for investigating the potential process of luminous quasar feedback on galaxies. We analyzed the rest-UV spectrum of an "overlapping trough" iron low-ionization broad absorption-line quasar (FeLoBAL) SDSS J135246.37+423923.5 using the novel spectral synthesis code SimBAL and discovered an extraordinarily fast and energetic BAL outflow. Our analysis revealed outflow velocities reaching ∼ -38,000 km s-1 with a velocity width of ∼ 10,000 km s-1, which is the largest FeLoBAL outflow velocity measured to date. The …


The Solar Energetic Particle Event Of 2010 August 14: Connectivity With The Solar Source Inferred From Multiple Spacecraft Observations And Modeling, D. Lario, R.-Y. Kwon, I. G. Richardson, N. E. Raouafi, B. J. Thompson, T. T. von Rosenvinge, M. L. Mays, P. A. Makela, H. Xie, H. M. Bain, M. Zhang, L. Zhao, H. V. Cane, A. Papaioannou, N. Thakur, P. Riley 2020 The Johns Hopkins University

The Solar Energetic Particle Event Of 2010 August 14: Connectivity With The Solar Source Inferred From Multiple Spacecraft Observations And Modeling, D. Lario, R.-Y. Kwon, I. G. Richardson, N. E. Raouafi, B. J. Thompson, T. T. Von Rosenvinge, M. L. Mays, P. A. Makela, H. Xie, H. M. Bain, M. Zhang, L. Zhao, H. V. Cane, A. Papaioannou, N. Thakur, P. Riley

Aerospace, Physics, and Space Science Faculty Publications

We analyze one of the first solar energetic particle (SEP) events of solar cycle 24 observed at widely separated spacecraft in order to assess the reliability of models currently used to determine the connectivity between the sources of SEPs at the Sun and spacecraft in the inner heliosphere. This SEP event was observed on 2010 August 14 by near-Earth spacecraft, STEREO-A (∼80° west of Earth) and STEREO-B (∼72° east of Earth). In contrast to near-Earth spacecraft, the footpoints of the nominal magnetic field lines connecting STEREO-A and STEREO-B with the Sun were separated from the region where the parent fast …


Improving The Background Of Gravitational-Wave Searches For Core Collapse Supernovae: A Machine Learning Approach, M. Cavaglià, S. Gaudio, T. Hansen, K. Staats, M. Szczepanczyk, M. Zanolin 2020 Missouri University of Science and Technology

Improving The Background Of Gravitational-Wave Searches For Core Collapse Supernovae: A Machine Learning Approach, M. Cavaglià, S. Gaudio, T. Hansen, K. Staats, M. Szczepanczyk, M. Zanolin

Physics Faculty Research & Creative Works

Based on the priorO1-O2observing runs, about30%of the data collected by Advanced LIGO and Virgo Internext observing runs are expected tobe single-interferometer data, i.e. they will be collected at times when only one detector in the network is operating in observing mode. Searches for gravitational-wave signals from supernova events do not rely on matched filtering techniques because of the stochastic nature of the signals. If a Galactic supernova occurs during single-interferometer times, separation of its unmodelled gravitational-wave signal from noise will be even more difficult due to lack of coherence between detectors. We present a novel machine learning method to perform …


Host-Galaxy Morphology Of 14 Local Active Galaxies As Imaged By The Hubble Space Telescope, Tomas Henry Snyder 2020 California Polytechnic State University, San Luis Obispo

Host-Galaxy Morphology Of 14 Local Active Galaxies As Imaged By The Hubble Space Telescope, Tomas Henry Snyder

Physics

Active galactic nuclei (AGNs) are galaxies with super-massive black holes, that are undergoing accretion, at their centers. The study of these objects provides us with a deeper understanding of how the black holes evolved along with their host galaxies since black hole mass is highly correlated with bulge mass. A sample of 66 AGNs were imaged using the Hubble Space Telescope (HST) and 14 of those are analyzed in this paper to determine their structure, bulge luminosity, and bulge type. The program GALFIT is implemented to determine these parameters, that will be used in further research in the future. These …


Neutron Energy Effects On Asteroid Deflection, Lansing S. Horan IV 2020 Air Force Institute of Technology

Neutron Energy Effects On Asteroid Deflection, Lansing S. Horan Iv

Theses and Dissertations

In the future, a hazardous asteroid will find itself on a collision course with Earth. It is an inevitability; the question is not if, but when. For asteroids of moderate size or larger, a nuclear device is one of humanity's only technologies capable of mitigating this threat via deflection on a timescale of less than a decade. This work examined how changing the output neutron energy from a nuclear device detonation affects asteroid deflection. The notional asteroid target was 300 meters in diameter and composed of silicon dioxide at a bulk density of 1.855 g/cm3. To calculate the …


Lack Of Debye And Meissner Screening In Strongly Magnetized Quark Matter At Intermediate Densities, Bo Feng, Efrain J. Ferrer, Israel Portillo 2020 The University of Texas Rio Grande Valley

Lack Of Debye And Meissner Screening In Strongly Magnetized Quark Matter At Intermediate Densities, Bo Feng, Efrain J. Ferrer, Israel Portillo

Physics & Astronomy Faculty Publications

We study the static responses of cold quark matter in the intermediate baryonic density region (characterized by a chemical potential μ) in the presence of a strong-magnetic field. We consider in particular, the so-called magnetic dual Chiral Density Wave (MDCDW) phase, which is materialized by an inhomogeneous condensate formed by a particle-hole pair. It is shown, that the MDCDW phase is more stable in the weak-coupling regime than the one considered in the magnetic catalysis of chiral symmetry braking phenomenon and even than the chiral symmetric phase that was expected to be realized at sufficiently high baryonic chemical potential. The …


A Writing Intensive Upper Division Astrophysics/Planetary Science Course, Laura M. Woodney 2020 California State University, San Bernardino

A Writing Intensive Upper Division Astrophysics/Planetary Science Course, Laura M. Woodney

Q2S Enhancing Pedagogy

This poster describes the major writing components of an upper division Astronomy or Planetary Science course. These components are intended to be integrated throughout the semester along with the content of the course. The papers the instructor chooses for the scaffolded assignments should compliment/enhance the content the students are learning in the course. This project used the "Backwards Design" method from Bean (2011, citation in poster): where the instructor first identifies the final project, determines what challenges the students will encounter attempting to do that project, and then builds scaffolded assignments intended to address each of these challenges. This presentation …


Fast Radio Bursts From Interacting Binary Neutron Star Systems, Bing Zhang 2020 University of Nevada, Las Vegas

Fast Radio Bursts From Interacting Binary Neutron Star Systems, Bing Zhang

Physics & Astronomy Faculty Research

Recent observations of repeating fast radio bursts (FRBs) suggest that some FRBs reside in an environment consistent with that of binary neutron star (BNS) mergers. The bursting rate for repeaters could be very high and the emission site is likely from a magnetosphere. We discuss a hypothesis of producing abundant repeating FRBs in BNS systems. Decades to centuries before a BNS system coalesces, the magnetospheres of the two neutron stars start to interact relentlessly. Abrupt magnetic reconnection accelerates particles, which emit coherent radio waves in bunches via curvature radiation. FRBs are detected as these bright radiation beams point toward Earth. …


Secondary Gravity Waves Generated By Breaking Mountain Waves Over Europe, Christopher J. Heale, Jonathan B. Snively, Katrina Bossert, S. L. Vadas, Lars Hoffmann, A. Dörnbrack, G. Stober, C. Jacobi 2020 Embry-Riddle Aeronautical University

Secondary Gravity Waves Generated By Breaking Mountain Waves Over Europe, Christopher J. Heale, Jonathan B. Snively, Katrina Bossert, S. L. Vadas, Lars Hoffmann, A. Dörnbrack, G. Stober, C. Jacobi

Publications

A strong mountain wave, observed over Central Europe on 12 January 2016, is simulated in 2D under two fixed background wind conditions representing opposite tidal phases. The aim of the simulation is to investigate the breaking of the mountain wave and subsequent generation of nonprimary waves in the upper atmosphere. The model results show that the mountain wave first breaks as it approaches a mesospheric critical level creating turbulence on horizontal scales of 8–30 km. These turbulence scales couple directly to horizontal secondary waves scales, but those scales are prevented from reaching the thermosphere by the tidal winds, which act …


Group Vibrational Mode Assignments As A Broadly Applicable Tool For Characterizing Ionomer Membrane Structure As A Function Of Degree Of Hydration, Neili Loupe, Khaldoon Abu-Hakmeh, Shuitao Gao, Luis Gonzalez, Matthew Ingargiola, Kayla Mathiowetz, Ryan Cruse, Jonathan Doan, Isaiah Salas, Nicholas Dimakis 2020 PSJA Thomas Jefferson T-STEM Early College HS

Group Vibrational Mode Assignments As A Broadly Applicable Tool For Characterizing Ionomer Membrane Structure As A Function Of Degree Of Hydration, Neili Loupe, Khaldoon Abu-Hakmeh, Shuitao Gao, Luis Gonzalez, Matthew Ingargiola, Kayla Mathiowetz, Ryan Cruse, Jonathan Doan, Isaiah Salas, Nicholas Dimakis

Physics & Astronomy Faculty Publications

Infrared spectra of Nafion, Aquivion, and the 3 M membrane were acquired during total dehydration of fully hydrated samples. Fully hydrated exchange sites are in a sulfonate form with a C3V local symmetry. The mechanical coupling of the exchange site to a side chain ether link gives rise to vibrational group modes that are classified as C3V modes. These mode intensities diminish concertedly with dehydration. When totally dehydrated, the sulfonic acid form of the exchange site is mechanically coupled to an ether link with no local symmetry. This gives rise to C1 group modes that …


Asteroid Belt Survival Through Stellar Evolution: Dependence On The Stellar Mass, Rebecca G. Martin, Mario Livio, Jeremy L. Smallwood, Cheng Chen 2020 University of Nevada, Las Vegas

Asteroid Belt Survival Through Stellar Evolution: Dependence On The Stellar Mass, Rebecca G. Martin, Mario Livio, Jeremy L. Smallwood, Cheng Chen

Physics & Astronomy Faculty Research

Polluted white dwarfs are generally accreting terrestrial-like material that may originate from a debris belt like the asteroid belt in the Solar system. ... See full text for complete abstract.


The Effects Of Disc Self-Gravity And Radiative Cooling On The Formation Of Gaps And Spirals By Young Planets, Shangjia Zhang, Zhaohuan Zhu 2020 University of Nevada, Las Vegas

The Effects Of Disc Self-Gravity And Radiative Cooling On The Formation Of Gaps And Spirals By Young Planets, Shangjia Zhang, Zhaohuan Zhu

Physics & Astronomy Faculty Research

We have carried out 2D hydrodynamical simulations to study the effects of disc self-gravity and radiative cooling on the formation of gaps and spirals. (1) With disc self-gravity included, we find stronger, more tightly wound spirals and deeper gaps in more massive discs. The deeper gaps are due to the larger Angular Momentum Flux (AMF) of the waves excited in more massive discs, as expected from the linear theory. The position of the secondary gap does not change, provided that the disc is not extremely massive (Q ≳ 2). (2) With radiative cooling included, the excited spirals become monotonically more …


Gj 1252 B: A 1.2 R⊕ Planet Transiting An M3 Dwarf At 20.4 Pc, A. Shporer, K. A. Collins, N. Astudillo-Defru, J. Irwin, X. Bonfils, K. I. Collins, E. Matthews, J. G. Winters, D. R. Anderson, J. D. Armstrong, D. Charbonneau, R. Cloutier, T. Daylan, T. Gan, M. N. Günther, C. Hellier, K. Horne, C. X. Huang, Eric L.N. Jensen, J. Kielkopf, E. Palle, R. Sefako, K. G. Stassun, T.-G. Tan, A. Vanderburg, G. R. Ricker, D. W. Latham, R. Vanderspek, S. Seager, J. N. Winn, J. M. Jenkins, K. Colon, C. D. Dressing, S. Léepine, P. S. Muirhead, M. E. Rose, J. D. Twicken, J. N. Villasenor 2020 Swarthmore College

Gj 1252 B: A 1.2 R⊕ Planet Transiting An M3 Dwarf At 20.4 Pc, A. Shporer, K. A. Collins, N. Astudillo-Defru, J. Irwin, X. Bonfils, K. I. Collins, E. Matthews, J. G. Winters, D. R. Anderson, J. D. Armstrong, D. Charbonneau, R. Cloutier, T. Daylan, T. Gan, M. N. Günther, C. Hellier, K. Horne, C. X. Huang, Eric L.N. Jensen, J. Kielkopf, E. Palle, R. Sefako, K. G. Stassun, T.-G. Tan, A. Vanderburg, G. R. Ricker, D. W. Latham, R. Vanderspek, S. Seager, J. N. Winn, J. M. Jenkins, K. Colon, C. D. Dressing, S. Léepine, P. S. Muirhead, M. E. Rose, J. D. Twicken, J. N. Villasenor

Physics & Astronomy Faculty Works

We report the discovery of GJ 1252 b, a planet with a radius of 1.193 ± 0.074 R⊕ and an orbital period of 0.52 days around an M3-type star (0.381 ± 0.019 M⊕, 0.391 ± 0.020 R⊕) located 20.385 ± 0.019 pc away. We use Transiting Exoplanet Survey Satellite (TESS) data, ground-based photometry and spectroscopy, Gaia astrometry, and high angular resolution imaging to show that the transit signal seen in the TESS data must originate from a transiting planet. We do so by ruling out all false-positive scenarios that attempt to explain the transit signal …


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