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2022

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Articles 151 - 180 of 415

Full-Text Articles in Astrophysics and Astronomy

Galactic Component Mapping Of Galaxy Ugc 2885 By Machine Learning Classification, Robin J. Kwik, Jinfei Wang, Pauline Barmby, Benne Holwerda Jul 2022

Galactic Component Mapping Of Galaxy Ugc 2885 By Machine Learning Classification, Robin J. Kwik, Jinfei Wang, Pauline Barmby, Benne Holwerda

Faculty and Staff Scholarship

Automating classification of galaxy components is important for understanding the formation and evolution of galaxies. Traditionally, only the larger galaxy structures such as the spiral arms, bulge, and disc are classified. Here we use machine learning (ML) pixel-by-pixel classification to automatically classify all galaxy components within digital imagery of massive spiral galaxy UGC 2885. Galaxy components include young stellar population, old stellar population, dust lanes, galaxy center, outer disc, and celestial background. We test three ML models: maximum likelihood classifier (MLC), random forest (RF), and support vector machine (SVM). We use high-resolution Hubble Space Telescope (HST) digital …

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Infrared Search For N-Butane And Trans-2-Butene In Titan’S Atmosphere, Brendan Steffens Jul 2022

Infrared Search For N-Butane And Trans-2-Butene In Titan’S Atmosphere, Brendan Steffens

Theses and Dissertations

This dissertation constitutes a study of the possible presence of trace hydrocarbons, namely n-butane (n-C4H10) and trans-2-butene (trans-2-C4H8) in Titan’s atmosphere. These molecules, both of which bear specific connections of interest to Titan’s astrobiological potential, are predicted by photochemical models to occur at detectable abundances within Titan’s atmosphere. In spite of this, neither has been detected to date, by any means. For this work, both of these molecules were characterized in the laboratory by obtaining a comprehensive set of highresolution, infrared cross section measurements at cold temperatures appropriate for Titan. In the case of n-butane, a pseudoline list (i.e. an …

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Climatology Of Deep O+ Dropouts In The Night-Time F-Region In Solar Minimum Measured By A Langmuir Probe Onboard The International Space Station, Shantanab Debchoudhury, Aroh Barjatya, Joseh I. Minow, Victoria N. Coffey, Linda N. Parker Jul 2022

Climatology Of Deep O+ Dropouts In The Night-Time F-Region In Solar Minimum Measured By A Langmuir Probe Onboard The International Space Station, Shantanab Debchoudhury, Aroh Barjatya, Joseh I. Minow, Victoria N. Coffey, Linda N. Parker

Publications

The Floating Potential Measurement Unit (FPMU) onboard the International Space Station includes a Wide sweeping Langmuir Probe (WLP) that has been operating in the F-region of the ionosphere at ∼400 km since 2006. While traditional Langmuir probe estimates include critical plasma parameters like electron density and temperature, we have also extracted the O+ percentage from the total ion constituents. This O+ composition dataset from the recent minimum in the Solar Cycle 24 reveals orbits with dropouts in O+ to below 80% of the total background ion density at ISS orbital altitudes. The observed O+ percentages during these dropouts are much …

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Beyond The Local Volume. Ii. Population Scaleheights And Ages Of Ultracool Dwarfs In Deep Hst/Wfc3 Parallel Fields, Christian Aganze, Adam J. Burgasser, Mathew Malkan, Christopher A. Theissen, Roberto A. Tejada Arevalo, Chih-Chun Hsu, Daniella C. Bardalez Gagliuffi, Russell E. Ryan Jr., Benne Holwerda Jul 2022

Beyond The Local Volume. Ii. Population Scaleheights And Ages Of Ultracool Dwarfs In Deep Hst/Wfc3 Parallel Fields, Christian Aganze, Adam J. Burgasser, Mathew Malkan, Christopher A. Theissen, Roberto A. Tejada Arevalo, Chih-Chun Hsu, Daniella C. Bardalez Gagliuffi, Russell E. Ryan Jr., Benne Holwerda

Faculty and Staff Scholarship

Ultracool dwarfs (UCDs) represent a significant proportion of stars in the Milky Way, and deep samples of these sources have the potential to constrain the formation history and evolution of low-mass objects in the Galaxy. Until recently, spectral samples have been limited to the local volume (d < 100 pc). Here, we analyze a sample of 164 spectroscopically characterized UCDs identified by Aganze et al. in the Hubble Space Telescope (HST) WFC3 Infrared Spectroscopic Parallel Survey (WISPS) and 3D-HST. We model the observed luminosity function using population simulations to place constraints on scaleheights, vertical velocity dispersions, and population ages as a function of spectral type. Our star counts are consistent with a power-law mass function and constant star formation history for UCDs, with vertical scaleheights of 249 pc for late-M dwarfs, 153 pc for L dwarfs, and 175 pc for T dwarfs. Using spatial and velocity dispersion relations, these scaleheights correspond to disk population ages of 3.6 Gyr for late-M dwarfs, 2.1 Gyr for L dwarfs, and 2.4 Gyr for T dwarfs, which are consistent with prior simulations that predict that L-type dwarfs are on average a younger and less dispersed population. There is an additional 1–2 Gyr systematic uncertainty on these ages due to variances in age-velocity relations. We use our population simulations to predict the UCD yield in the James Webb Space Telescope PASSAGES survey, a similar and deeper survey to WISPS and 3D-HST, and find that it will produce a comparably sized UCD sample, albeit dominated by thick disk and halo sources.

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Coexistence Of Extended And Localized States In The One-Dimensional Non-Hermitian Anderson Model, Cem Yuce, Hamidreza Ramezani Jul 2022

Coexistence Of Extended And Localized States In The One-Dimensional Non-Hermitian Anderson Model, Cem Yuce, Hamidreza Ramezani

Physics & Astronomy Faculty Publications

In one-dimensional Hermitian tight-binding models, mobility edges separating extended and localized states can appear in the presence of properly engineered quasiperiodical potentials and coupling constants. On the other hand, mobility edges do not exist in a one-dimensional Anderson lattice since localization occurs whenever a diagonal disorder through random numbers is introduced. Here we consider a nonreciprocal non-Hermitian lattice and show that the coexistence of extended and localized states appears with or without diagonal disorder in the topologically nontrivial region. We discuss that the mobility edges appear basically due to the boundary condition sensitivity of the nonreciprocal non-Hermitian lattice.

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Table Of Contents Jun 2022

Table Of Contents

Journal of the South Carolina Academy of Science

No abstract provided.

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Staerkel Planetarium Marking 35 Years Of Projecting The Stars, Erik Johnson Jun 2022

Staerkel Planetarium Marking 35 Years Of Projecting The Stars, Erik Johnson

Natural Science Faculty

Visitors to the Staerkel Planetarium are introduced to "Carl" when they walk in the dome. Some people mistake Carl for a telescope in an observatory, but Carl puts "stars" on the dome instead of collecting light from stars. "Carl" is the Carl Zeiss Model M 1015-star projector, an intricate piece of machinery that has been at Parkland College since the planetarium opened 35 years ago.

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Complex Energies And The Lambert W Function, A Das, B.G. Sidharth, K. Roberts, Sree Ram Valluri Jun 2022

Complex Energies And The Lambert W Function, A Das, B.G. Sidharth, K. Roberts, Sree Ram Valluri

Physics and Astronomy Publications

We apply the Lambert W function in the context of complex energy values in statistical systems of fermions and bosons. We derive the condition for the transformation connecting fermions and bosons. We discuss the physical significance of these results and investigate the conditions under which bosonization effects take place. The fermion and boson statistical and structural distributions discussed in this work suggest the possibility of their extensions to generalized Planck distributions.

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Search For Multimessenger Signals In Nova Coincident With Ligo/Virgo Detections, M. A. Acero, P. Adamson, L. Aliaga, T. Alion, V. Alakhberdian, N. Anfimov, A. Antoshkin, L. Asquith, A. Aurisano, A. Back, C. Backhouse, M. Biard, N. Balashov, P. Baldi, B. A. Bambah, S. Bashar, K. Bays, S. Bending, R. Bernstein, V. Bhatnagar, Roberto Petti, Et. Al. Jun 2022

Search For Multimessenger Signals In Nova Coincident With Ligo/Virgo Detections, M. A. Acero, P. Adamson, L. Aliaga, T. Alion, V. Alakhberdian, N. Anfimov, A. Antoshkin, L. Asquith, A. Aurisano, A. Back, C. Backhouse, M. Biard, N. Balashov, P. Baldi, B. A. Bambah, S. Bashar, K. Bays, S. Bending, R. Bernstein, V. Bhatnagar, Roberto Petti, Et. Al.

Faculty Publications

Using the NOvA neutrino detectors, a broad search has been performed for any signal coincident with 28 gravitational wave events detected by the LIGO/Virgo Collaboration between September 2015 and July 2019. For all of these events, NOvA is sensitive to possible arrival of neutrinos and cosmic rays of GeV and higher energies. For five (seven) events in the NOvA Far (Near) Detector, timely public alerts from the LIGO/Virgo Collaboration allowed recording of MeV-scale events. No signal candidates were found.

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Narrowband Searches For Continuous And Long-Duration Transient Gravitational Waves From Known Pulsars In The Ligo-Virgo Third Observing Run, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, Teviet Creighton, Mario C. Diaz, Francisco Llamas, Soma Mukherjee, Volker Quetschke, Wenhui Wang Jun 2022

Narrowband Searches For Continuous And Long-Duration Transient Gravitational Waves From Known Pulsars In The Ligo-Virgo Third Observing Run, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, Teviet Creighton, Mario C. Diaz, Francisco Llamas, Soma Mukherjee, Volker Quetschke, Wenhui Wang

Physics & Astronomy Faculty Publications

Isolated neutron stars that are asymmetric with respect to their spin axis are possible sources of detectable continuous gravitational waves. This paper presents a fully coherent search for such signals from eighteen pulsars in data from LIGO and Virgo's third observing run (O3). For known pulsars, efficient and sensitive matched-filter searches can be carried out if one assumes the gravitational radiation is phase-locked to the electromagnetic emission. In the search presented here, we relax this assumption and allow both the frequency and the time derivative of the frequency of the gravitational waves to vary in a small range around those …

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Expected Sensitivity To 128Te Neutrinoless Double Beta Decay With The Cuore Teo2 Cryogenic Bolometers, V. Dompé, D. Q. Adams, C. Alduino, K. Alfonso, Frank Avignone Iii Jun 2022

Expected Sensitivity To 128Te Neutrinoless Double Beta Decay With The Cuore Teo2 Cryogenic Bolometers, V. Dompé, D. Q. Adams, C. Alduino, K. Alfonso, Frank Avignone Iii

Faculty Publications

The CUORE experiment is a ton-scale array of TeO2 cryogenic bolometers located at the underground Laboratori Nazionali del Gran Sasso of Istituto Nazionale di Fisica Nucleare (INFN), in Italy. The CUORE detector consists of 988 crystals operated as source and detector at a base temperature of ∼ 10 mK. Such cryogenic temperature is reached and maintained by means of a custom built cryogen-free dilution cryostat, designed with the aim of minimizing the vibrational noise and the environmental radioactivity. The primary goal of CUORE is the search for neutrinoless double beta decay of 130Te, but thanks to its …

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From Equal-Mass To Extreme-Mass-Ratio Binary Inspirals: Simulation Tools For Next Generation Gravitational Wave Detectors, Samuel Douglas Cupp Jun 2022

From Equal-Mass To Extreme-Mass-Ratio Binary Inspirals: Simulation Tools For Next Generation Gravitational Wave Detectors, Samuel Douglas Cupp

LSU Doctoral Dissertations

Current numerical codes can successfully evolve similar-mass binary black holes systems, and these numerical waveforms contributed to the success of the LIGO Collaboration's detection of gravitational waves. LIGO requires high resolution numerical waveforms for detection and parameter estimation of the source. Great effort was expended over several decades to produce the numerical methods used today. However, future detectors will require further improvements to numerical techniques to take full advantage of their detection capabilities. For example, the Laser Interferometer Space Antenna (LISA) will require higher resolution simulations of similar-mass-ratio systems than LIGO. LISA will also be able to detect extreme-mass-ratio inspiral …

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A Repeating Fast Radio Burst Associated With A Persistent Radio Source, C.-H. Niu, K. Aggarwal, D. Li, X. Zhang, S. Chatterjee, C.-W. Tsai, W. Yu, C. J. Law, S. Burke-Spolaor, J. M. Cordes, Y.-K. Zhang, S. K. Ocker, J.-M. Yao, P. Wang, Y. Feng, Y. Niino, C. Bochenek, M. Cruces, L. Connor, J.-A. Jiang, S. Dai, R. Luo, G.-D. Li, C.-C. Miao, J.-R. Niu, R. Anna-Thomas, J. Sydnor, D. Stern, W.-Y. Wang, M Yuan, Y.-L. Yue, D.-J. Zhou, Z Yan, W.-W. Zhu, B. Zhang Jun 2022

A Repeating Fast Radio Burst Associated With A Persistent Radio Source, C.-H. Niu, K. Aggarwal, D. Li, X. Zhang, S. Chatterjee, C.-W. Tsai, W. Yu, C. J. Law, S. Burke-Spolaor, J. M. Cordes, Y.-K. Zhang, S. K. Ocker, J.-M. Yao, P. Wang, Y. Feng, Y. Niino, C. Bochenek, M. Cruces, L. Connor, J.-A. Jiang, S. Dai, R. Luo, G.-D. Li, C.-C. Miao, J.-R. Niu, R. Anna-Thomas, J. Sydnor, D. Stern, W.-Y. Wang, M Yuan, Y.-L. Yue, D.-J. Zhou, Z Yan, W.-W. Zhu, B. Zhang

Physics & Astronomy Faculty Research

The dispersive sweep of fast radio bursts (FRBs) has been used to probe the ionized baryon content of the intergalactic medium1, which is assumed to dominate the total extragalactic dispersion. Although the host-galaxy contributions to the dispersion measure appear to be small for most FRBs2, in at least one case there is evidence for an extreme magneto-ionic local environment3,4 and a compact persistent radio source5. Here we report the detection and localization of the repeating FRB 20190520B, which is co-located with a compact, persistent radio source and associated with a dwarf host galaxy of high specific-star-formation rate at a redshift …

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Propionamide (C2h5conh2): The Largest Peptide-Like Molecule In Space (Vol 919, 4, 2021), Juan Li, Junzhi Wang, Xing Lu, Vadim Ilyushin, Roman A. Motiyenko, Qian Gou, Eugene A. Alekseev, Donghui Quan Dr., Laurent Margules, Feng Gao, Frank J. Lovas, Yajun Wu, Edwin Bergin, Shanghuo Li, Zhiqiang Shen, Fujun Du, Meng Li, Siqi Zheng, Xingwu Zheng Jun 2022

Propionamide (C2h5conh2): The Largest Peptide-Like Molecule In Space (Vol 919, 4, 2021), Juan Li, Junzhi Wang, Xing Lu, Vadim Ilyushin, Roman A. Motiyenko, Qian Gou, Eugene A. Alekseev, Donghui Quan Dr., Laurent Margules, Feng Gao, Frank J. Lovas, Yajun Wu, Edwin Bergin, Shanghuo Li, Zhiqiang Shen, Fujun Du, Meng Li, Siqi Zheng, Xingwu Zheng

EKU Faculty and Staff Scholarship

No abstract provided.

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Introduction To Classical Field Theory, Charles G. Torre Jun 2022

Introduction To Classical Field Theory, Charles G. Torre

All Complete Monographs

This is an introduction to classical field theory. Topics treated include: Klein-Gordon field, electromagnetic field, scalar electrodynamics, Dirac field, Yang-Mills field, gravitational field, Noether theorems relating symmetries and conservation laws, spontaneous symmetry breaking, Lagrangian and Hamiltonian formalisms.

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All-Sky, All-Frequency Directional Search For Persistent Gravitational-Waves From Advanced Ligo's And Advanced Virgo's First Three Observing Runs, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, Teviet Creighton, Mario C. Diaz, Francisco Llamas, Soma Mukherjee, Volker Quetschke, Wenhui Wang Jun 2022

All-Sky, All-Frequency Directional Search For Persistent Gravitational-Waves From Advanced Ligo's And Advanced Virgo's First Three Observing Runs, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, Teviet Creighton, Mario C. Diaz, Francisco Llamas, Soma Mukherjee, Volker Quetschke, Wenhui Wang

Physics & Astronomy Faculty Publications

We present the first results from an all-sky all-frequency (ASAF) search for an anisotropic stochastic gravitational-wave background using the data from the first three observing runs of the Advanced LIGO and Advanced Virgo detectors. Upper limit maps on broadband anisotropies of a persistent stochastic background were published for all observing runs of the LIGO-Virgo detectors. However, a broadband analysis is likely to miss narrowband signals as the signal-to-noise ratio of a narrowband signal can be significantly reduced when combined with detector output from other frequencies. Data folding and the computationally efficient analysis pipeline, PyStoch, enable us to perform the radiometer …

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Helium-Like X-Ray Line Complexes Show That The Hottest Plasma On The O Supergiant Ζ Puppis Is In Its Wind, David H. Cohen, Ariel M. Overdorff, M. A. Leutenegger, M. Gagné, V. Petit, A. David-Uraz Jun 2022

Helium-Like X-Ray Line Complexes Show That The Hottest Plasma On The O Supergiant Ζ Puppis Is In Its Wind, David H. Cohen, Ariel M. Overdorff, M. A. Leutenegger, M. Gagné, V. Petit, A. David-Uraz

Physics & Astronomy Faculty Works

We present an analysis of Chandra grating spectra of key helium-like line complexes to put constraints on the location with respect to the photosphere of the hottest (T ≳ 6 × 10⁶ K) plasma in the wind of the O supergiant ζ Pup and to explore changes in the 18 yr between two sets of observations of this star. We fit two models—one empirical and one wind-shock-based—to the S XV, Si XIII, and Mg XI line complexes and show that an origin in the wind flow, above r ≈ 1.5 R∗, is strongly favoured over an origin less than 0.3 …

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Exploring Changes In Quasar Spectral Energy Distributions Across C Iv Parameter Space, Angelica B. Rivera, Gordon T. Richards, Sarah C. Gallagher, Trevor V. Mccaffrey, Amy L. Rankine, Paul C. Hewett, Ohad Shemmer Jun 2022

Exploring Changes In Quasar Spectral Energy Distributions Across C Iv Parameter Space, Angelica B. Rivera, Gordon T. Richards, Sarah C. Gallagher, Trevor V. Mccaffrey, Amy L. Rankine, Paul C. Hewett, Ohad Shemmer

Physics and Astronomy Publications

We examine the UV/X-ray properties of 1378 quasars in order to link empirical correlations to theoretical models of the physical mechanisms dominating quasars as a function of mass and accretion rate. The clarity of these correlations is improved when (1) using C iv broad emission line equivalent width (EQW) and blueshift (relative to systemic) values calculated from high signal-to-noise ratio reconstructions of optical/UV spectra and (2) removing quasars expected to be absorbed based on their UV/X-ray spectral slopes. In addition to using the traditional C iv parameter space measures of C iv EQW and blueshift, we define a “C iv …

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Toi-1696: A Nearby M4 Dwarf With A 3 R⊕ Planet In The Neptunian Desert, M. Mori, J. H. Livingston, J. De Leon, N. Narita, T. Hirano, A. Fukui, K. A. Collins, N. Fujita, Y. Hori, H. T. Ishikawa, K. Kawauchi, K. G. Stassun, N. Watanabe, S. Giacalone, R. Gore, A. Schroeder, C. D. Dressing, A. Bieryla, Eric L.N. Jensen, B. Massey, A. Shporer, M. Kuzuhara, D. Charbonneau, D. R. Ciardi, J. P. Doty, E. Esparza-Borges, H. Harakawa, K. Hodapp, M. Ikoma, K. Ikuta, K. Isogai, J. M. Jenkins, T. Kagetani, T. Kimura, T. Kodama, T. Kotani, V. Krishnamurthy, T. Kudo, S. Kurita, T. Kurokawa, N. Kusakabe, D. W. Latham, B. Mclean, F. Murgas, J. Nishikawa, T. Nishiumi, M. Omiya, H. P. Osborn, E. Palle, H. Parviainen, G. R. Ricker, S. Seager, T. Serizawa, H.-Y. Teng, Y. Terada, J. D. Twicken, A. Ueda, R. Vanderspek, S. Vievard, J. N. Winn, Y. Zou, M. Tamura Jun 2022

Toi-1696: A Nearby M4 Dwarf With A 3 R⊕ Planet In The Neptunian Desert, M. Mori, J. H. Livingston, J. De Leon, N. Narita, T. Hirano, A. Fukui, K. A. Collins, N. Fujita, Y. Hori, H. T. Ishikawa, K. Kawauchi, K. G. Stassun, N. Watanabe, S. Giacalone, R. Gore, A. Schroeder, C. D. Dressing, A. Bieryla, Eric L.N. Jensen, B. Massey, A. Shporer, M. Kuzuhara, D. Charbonneau, D. R. Ciardi, J. P. Doty, E. Esparza-Borges, H. Harakawa, K. Hodapp, M. Ikoma, K. Ikuta, K. Isogai, J. M. Jenkins, T. Kagetani, T. Kimura, T. Kodama, T. Kotani, V. Krishnamurthy, T. Kudo, S. Kurita, T. Kurokawa, N. Kusakabe, D. W. Latham, B. Mclean, F. Murgas, J. Nishikawa, T. Nishiumi, M. Omiya, H. P. Osborn, E. Palle, H. Parviainen, G. R. Ricker, S. Seager, T. Serizawa, H.-Y. Teng, Y. Terada, J. D. Twicken, A. Ueda, R. Vanderspek, S. Vievard, J. N. Winn, Y. Zou, M. Tamura

Physics & Astronomy Faculty Works

We present the discovery and validation of a temperate sub-Neptune around the nearby mid-M dwarf TIC 470381900 (TOI-1696), with a radius of 3.09 ± 0.11 R⊕ and an orbital period of 2.5 days, using a combination of Transiting Exoplanets Survey Satellite (TESS) and follow-up observations using ground-based telescopes. Joint analysis of multiband photometry from TESS, Multicolor Simultaneous Camera for studying Atmospheres of Transiting exoplanets (MuSCAT), MuSCAT3, Sinistro, and KeplerCam confirmed the transit signal to be achromatic as well as refined the orbital ephemeris. High-resolution imaging with Gemini/'Alopeke and high-resolution spectroscopy with the Subaru InfraRed Doppler (IRD) confirmed that there …

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First Joint Observation By The Underground Gravitational-Wave Detector Kagra With Geo 600, R. Abbott, H. Abe, Fausto Acernese, K. Ackley, N. Adhikari, Michael G. Benjamin, Teviet Creighton, Mario C. Diaz, Francisco Llamas, Soma Mukherjee, Gaukhar Nurbek, Volker Quetschke, Wenhui Wang Jun 2022

First Joint Observation By The Underground Gravitational-Wave Detector Kagra With Geo 600, R. Abbott, H. Abe, Fausto Acernese, K. Ackley, N. Adhikari, Michael G. Benjamin, Teviet Creighton, Mario C. Diaz, Francisco Llamas, Soma Mukherjee, Gaukhar Nurbek, Volker Quetschke, Wenhui Wang

Physics & Astronomy Faculty Publications

We report the results of the first joint observation of the KAGRA detector with GEO 600. KAGRA is a cryogenic and underground gravitational-wave detector consisting of a laser interferometer with 3 km arms, located in Kamioka, Gifu, Japan. GEO 600 is a British–German laser interferometer with 600 m arms, located near Hannover, Germany. GEO 600 and KAGRA performed a joint observing run from April 7 to 20, 2020. We present the results of the joint analysis of the GEO–KAGRA data for transient gravitational-wave signals, including the coalescence of neutron-star binaries and generic unmodeled transients. We also perform dedicated searches for …

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Images Of Embedded Jovian Planet Formation At A Wide Separation Around Ab Aurigae, Thayne Currie, Kellen Lawson, Glenn Schneider, Wladimir Lyra, John Wisniewski, Carol Grady, Olivier Guyon, Motohide Tamura, Takayuki Kotani, Hajime Kawahara, Timothy Brandt, Taichi Uyama, Takayuki Muto, Ruobing Dong, Tomoyuki Kudo, Jun Hashimoto, Misato Fukagawa, Kevin Wagner, Julien Lozi, Jeffrey Chilcote, Taylor Tobin, Tyler Groff, Kimberly Ward-Duong, William Januszewski, Barnaby Norris, Peter Tuthill, Nienke Van Der Marel, Michael Sitko, Vincent Deo, Sebastien Vievard, Nemanja Jovanovic, Frantz Martinache Jun 2022

Images Of Embedded Jovian Planet Formation At A Wide Separation Around Ab Aurigae, Thayne Currie, Kellen Lawson, Glenn Schneider, Wladimir Lyra, John Wisniewski, Carol Grady, Olivier Guyon, Motohide Tamura, Takayuki Kotani, Hajime Kawahara, Timothy Brandt, Taichi Uyama, Takayuki Muto, Ruobing Dong, Tomoyuki Kudo, Jun Hashimoto, Misato Fukagawa, Kevin Wagner, Julien Lozi, Jeffrey Chilcote, Taylor Tobin, Tyler Groff, Kimberly Ward-Duong, William Januszewski, Barnaby Norris, Peter Tuthill, Nienke Van Der Marel, Michael Sitko, Vincent Deo, Sebastien Vievard, Nemanja Jovanovic, Frantz Martinache

Astronomy: Faculty Publications

Direct images of protoplanets embedded in disks around infant stars provide the key to understanding the formation of gas giant planets such as Jupiter. Using the Subaru Telescope and the Hubble Space Telescope, we find evidence for a Jovian protoplanet around AB Aurigae orbiting at a wide projected separation (~93 au), probably responsible for multiple planet-induced features in the disk. Its emission is reproducible as reprocessed radiation from an embedded protoplanet. We also identify two structures located at 430–580 au that are candidate sites of planet formation. These data reveal planet formation in the embedded phase and a protoplanet discovery …

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A Comparison Of Exotic And Pyraf In Analyzing Exoplanet Transits, Kailei A. Gallup Jun 2022

A Comparison Of Exotic And Pyraf In Analyzing Exoplanet Transits, Kailei A. Gallup

Physics

In this paper we discuss the data analysis processes using PyRaf, a Python-based version of IRAF, which is one of the most commonly used coding softwares in the astronomy community, as well as the analysis process using EXOTIC. Additionally, we will compare the outcomes from each process to determine if either has significant benefits over the other.

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Recreating Nasa Images Using Hubble Data: Two Populations Of Stars In Messier 5, Adam N. Looper Jun 2022

Recreating Nasa Images Using Hubble Data: Two Populations Of Stars In Messier 5, Adam N. Looper

Physics

This project seeks to recreate a color photo from NASA using Hubble data that shows the two distinct populations of stars in the cluster. Although the colored image displays the two types of stars, scientists often recolor astronomical pictures for two reasons: in order to clearly define objects, or to convert an image taken outside the visible spectrum into color. Thus, overlapping Hubble images colored according to filter should verify that there are two populations of stars in Messier 5, and the colored NASA photograph is valid in highlighting the unusual distribution of stars.

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A Self-Consistent Model For Brown Dwarf Populations, R. E. Ryan Jr., P. Thorman, C. Aganze, A. J. Burgasser, S. H. Cohen, N. P. Hathi, Benne Holwerda, N. Pirzkal, R. A. Windhorst Jun 2022

A Self-Consistent Model For Brown Dwarf Populations, R. E. Ryan Jr., P. Thorman, C. Aganze, A. J. Burgasser, S. H. Cohen, N. P. Hathi, Benne Holwerda, N. Pirzkal, R. A. Windhorst

Faculty and Staff Scholarship

We present a self-consistent model of the Milky Way to reproduce the observed distributions (spectral type, absolute J-band magnitude, effective temperature) and total velocity dispersion of brown dwarfs. For our model, we adopt parametric forms for the star formation history and initial-mass function, published evolutionary models, and theoretical age–velocity relations. Using standard Markov Chain Monte Carlo methods, we derive a power-law index of the initial-mass function of α = −0.71 ± 0.11, which is an improvement over previous studies. We consider a gamma-function form for the star formation history, though we find that this complex model is only slightly …

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Waves And Oscillations In A Sunspot: Observations And Modeling Of Noaa Ar 12470, Yi Chai May 2022

Waves And Oscillations In A Sunspot: Observations And Modeling Of Noaa Ar 12470, Yi Chai

Dissertations

Waves and oscillations are important solar phenomena not only because they can propagate and dissipate energy in the chromosphere, but also because they carry information about the structure of the atmosphere in which they propagate. Among these phenomena, the one of the most interesting ones occurs in the sunspot umbra. In this area, continuously propagating magnetohydrodynamic (MHD) waves generated from below the photosphere create the famous 3-minute sunspot umbral oscillations that affect the line profile of spectral lines due to temperature, density, and velocity changes of the plasma in the region. In the past decades, numerous observations and models have …

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Correlations Between The Rotations And Magnetospheres Of The Terrestrial Planets And The Sun's Formation In Our Solar System, Fred J. Cadieu May 2022

Correlations Between The Rotations And Magnetospheres Of The Terrestrial Planets And The Sun's Formation In Our Solar System, Fred J. Cadieu

Publications and Research

Correlations between the rotations of the terrestrial planets in our solar system and the magnetic field of the Sun have been previously noted. These correlations account for the opposite rotation of Venus as a result of the magnetic field of the Sun being dragged across the conducting core of Venus. Currently the Sun’s magnetic field is not sufficiently strong to account for the proposed correlations. But recently meteorite paleomagnetism measurements have indicated that during the Sun’s formation the magnetic field of the Sun was of sufficient strength to have resulted in the observed correlations. As a part of these correlations …

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Searches For Gravitational Waves From Known Pulsars At Two Harmonics In The Second And Third Ligo-Virgo Observing Runs, R. Abbott, H. Abe, F. Acernese, Teviet Creighton, M. G. Benjamin, Mario C. Diaz, Francisco Llamas, Soma Mukherjee, Gaukhar Nurbek, Volker Quetschke, Wenhui Wang May 2022

Searches For Gravitational Waves From Known Pulsars At Two Harmonics In The Second And Third Ligo-Virgo Observing Runs, R. Abbott, H. Abe, F. Acernese, Teviet Creighton, M. G. Benjamin, Mario C. Diaz, Francisco Llamas, Soma Mukherjee, Gaukhar Nurbek, Volker Quetschke, Wenhui Wang

Physics & Astronomy Faculty Publications

We present a targeted search for continuous gravitational waves (GWs) from 236 pulsars using data from the third observing run of LIGO and Virgo (O3) combined with data from the second observing run (O2). Searches were for emission from the l = m = 2 mass quadrupole mode with a frequency at only twice the pulsar rotation frequency (single harmonic) and the l = 2, m = 1, 2 modes with a frequency of both once and twice the rotation frequency (dual harmonic). No evidence of GWs was found, so we present 95% credible upper limits on the strain amplitudes …

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X-Ray Observation Of The Roche-Lobe-Filling White Dwarf Plus Hot Subdwarf System Ztf J213056.71+442046.5, S. Mereghetti, N. La Palombara, T. Kupfer, T. R. Marsh, C. M. Copperwheat, K. Deshmukh, P. Esposito, T. Maccarone, F. Pintore, Liliana Rivera Sandoval May 2022

X-Ray Observation Of The Roche-Lobe-Filling White Dwarf Plus Hot Subdwarf System Ztf J213056.71+442046.5, S. Mereghetti, N. La Palombara, T. Kupfer, T. R. Marsh, C. M. Copperwheat, K. Deshmukh, P. Esposito, T. Maccarone, F. Pintore, Liliana Rivera Sandoval

Physics & Astronomy Faculty Publications

ZTF J213056.71+442046.5 is the prototype of a small class of recently discovered compact binaries composed of a white dwarf and a hot subdwarf that fills its Roche lobe. Its orbital period of only 39 minutes is the shortest known for the objects in this class. Evidence for a high orbital inclination (i = 86°) and for the presence of an accretion disk has been inferred from a detailed modeling of its optical photometric and spectroscopic data. We report the results of an XMM-Newton observation carried out on 2021 January 7. ZTF J213056.71+442046.5 was clearly detected by the Optical Monitor, …

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To The Moon And Mars And Back To The Archives: Working With Modern Space Collections At The University Of Arizona Libraries, Molly Stothert-Maurer, Lisa E. Duncan May 2022

To The Moon And Mars And Back To The Archives: Working With Modern Space Collections At The University Of Arizona Libraries, Molly Stothert-Maurer, Lisa E. Duncan

Journal of Western Archives

With a long history at the University of Arizona with excellence in the lunar and planetary sciences, the University of Arizona Libraries Special Collections has increased its collecting of the History of Science and Technology. These large, modern space collections pose unique challenges and require specific needs to be addressed in order for the collections to be stored, processed and made available for access. It is essential for archivists working with these collections to ask their donors the right questions and learn the limitations and restrictions that often come with acquiring modern space collections. Archives around the country have started …

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Du Undergraduate Showcase: Research, Scholarship, And Creative Works: Abstracts, Emma Aggeler, Elena Arroway, Daisy T. Booker, Justin Bravo, Kyle Bucholtz, Megan Burnham, Nicole Choi, Spencer Cockerell, Rosie Contino, Jackson Garske, Kaitlyn Glover, Caroline Hamilton, Haley Hartmann, Madalyne Heiken, Colin Holter, Leah Huzjak, Alyssa Jeng, Cole Jernigan, Chad Kashiwa, Adelaide Kerenick, Emily King, Abigail Langeberg, Maddie Leake, Meredith Lemons, Alec Mackay, Greer Mckinley, Ori Miller, Guy Milliman, Katherine Miromonti, Audrey Mitchell, Lauren Moak, Megan Morrell, Gelella Nebiyu, Zdenek Otruba, Toni V. Panzera, Kassidy Patarino, Sneha Patil, Alexandra Penney, Kevin Persky, Caitlin Pham, Gabriela Recinos, Mary Ringgenberg, Chase Routt, Olivia Schneider, Roman Shrestha, Arlo Simmerman, Alec Smith, Tessa Smith, Nhi-Lac Thai, Kyle Thurmann, Casey Tindall, Amelia Trembath, Maria Trubetskaya, Zachary Vangelisti, Peter Vo, Abby Walker, David Winter, Grayden Wolfe, Leah York May 2022

Du Undergraduate Showcase: Research, Scholarship, And Creative Works: Abstracts, Emma Aggeler, Elena Arroway, Daisy T. Booker, Justin Bravo, Kyle Bucholtz, Megan Burnham, Nicole Choi, Spencer Cockerell, Rosie Contino, Jackson Garske, Kaitlyn Glover, Caroline Hamilton, Haley Hartmann, Madalyne Heiken, Colin Holter, Leah Huzjak, Alyssa Jeng, Cole Jernigan, Chad Kashiwa, Adelaide Kerenick, Emily King, Abigail Langeberg, Maddie Leake, Meredith Lemons, Alec Mackay, Greer Mckinley, Ori Miller, Guy Milliman, Katherine Miromonti, Audrey Mitchell, Lauren Moak, Megan Morrell, Gelella Nebiyu, Zdenek Otruba, Toni V. Panzera, Kassidy Patarino, Sneha Patil, Alexandra Penney, Kevin Persky, Caitlin Pham, Gabriela Recinos, Mary Ringgenberg, Chase Routt, Olivia Schneider, Roman Shrestha, Arlo Simmerman, Alec Smith, Tessa Smith, Nhi-Lac Thai, Kyle Thurmann, Casey Tindall, Amelia Trembath, Maria Trubetskaya, Zachary Vangelisti, Peter Vo, Abby Walker, David Winter, Grayden Wolfe, Leah York

DU Undergraduate Research Journal Archive

Abstracts from the DU Undergraduate Showcase.

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