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Astrophysics and Astronomy

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2023

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Articles 31 - 60 of 129

Full-Text Articles in Physical Sciences and Mathematics

On The Frequencies Of Circumbinary Discs In Protostellar Systems, D. Elsender, M. R. Bate, B. S. Lakeland, Eric L.N. Jensen, S. H. Lubow Aug 2023

On The Frequencies Of Circumbinary Discs In Protostellar Systems, D. Elsender, M. R. Bate, B. S. Lakeland, Eric L.N. Jensen, S. H. Lubow

Physics & Astronomy Faculty Works

We report the analysis of circumbinary (CB) discs formed in a radiation hydrodynamical simulation of star cluster formation. We consider both pure binary stars and pairs within triple and quadruple systems. The protostellar systems are all young (ages < 10⁵ yrs). We find that the systems that host a CB disc have a median separation of ≈11 au, and the median characteristic radius of the discs is ≈64 au. We find that 89 per cent of pure binaries with semimajor axes a < 1 au have a CB disc, and the occurrence rate of CB discs is bimodal with log-separation in pure binaries with a second peak at a ≈ 50 au. Systems with a > 100 au almost never have a CB disc. The median size of a CB disc is between ≈5 and 6 a depending on the order of the system, with higher order systems having larger discs relative to binary separation. We find the underlying distributions of mutual inclination between CB discs and binary orbits from …

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Two Warm Neptunes Transiting Hip 9618 Revealed By Tess And Cheops, H. P. Osborn, G. Nowak, G. Hébrard, T. Masseron, J. Lillo-Box, E. Pallé, A. Bekkelien, H.-G. Florén, P. Guterman, A. E. Simon, V. Adibekyan, A. Bieryla, L. Borsato, A. Brandeker, D. R. Ciardi, A. Collier Cameron, K. A. Collins, J. A. Egger, D. Gandolfi, M. J. Hooton, D. W. Latham, M. Lendl, E. C. Matthews, A. Tuson, S. Ulmer-Moll, A. Vanderburg, T. G. Wilson, C. Ziegler, Y. Alibert, R. Alonso, G. Anglada, L. Arnold, J. Asquier, D. Barrado Y Navascues, W. Baumjohann, T. Beck, A. A. Belinski, W. Benz, F. Biondi, I. Boisse, X. Bonfils, C. Broeg, L. A. Buchhave, T. Bárczy, S. C. C. Barros, J. Cabrera, C. Cardona Guillen, I. Carleo, A. Castro-González, S. Charnoz, J. Christiansen, P. Cortes-Zuleta, S. Csizmadia, S. Dalal, M. B. Davies, M. Deleuil, X. Delfosse, L. Delrez, B.-O. Demory, A. B. Dunlavey, D. Ehrenreich, A. Erikson, R. B. Fernandes, A. Fortier, T. Forveille, L. Fossati, M. Fridlund, M. Gillon, R. F. Goeke, M. V. Goliguzova, E. J. Gonzales, M. N. Günther, M. Güdel, N. Heidari, C. E. Henze, S. Howell, S. Hoyer, J. I. Frey, K. G. Isaak, J. M. Jenkins, F. Kiefer, L. Kiss, J. Korth, P. F. L. Maxted, J. Laskar, A. Lecavelier Des Etangs, C. Lovis, M. B. Lund, R. Luque, D. Magrin, J. M. Almenara, E. Martioli, M. Mecina, J. V. Medina, D. Moldovan, M. Morales-Calderón, G. Morello, C. Moutou, F. Murgas, Eric L.N. Jensen, V. Nascimbeni, G. Olofsson, R. Ottensamer, I. Pagano, G. Peter, G. Piotto, D. Pollacco, D. Queloz, R. Ragazzoni, N. Rando, H. Rauer, I. Ribas, G. Ricker, O. D. S. Demangeon, A. M. S. Smith, N. Santos, G. Scandariato, S. Seager, S. G. Sousa, M. Steller, G. M. Szabó, D. Ségransan, N. Thomas, S. Udry, B. Ulmer, V. Van Grootel, R. Vanderspek, N. Walton, J. N. Winn Aug 2023

Two Warm Neptunes Transiting Hip 9618 Revealed By Tess And Cheops, H. P. Osborn, G. Nowak, G. Hébrard, T. Masseron, J. Lillo-Box, E. Pallé, A. Bekkelien, H.-G. Florén, P. Guterman, A. E. Simon, V. Adibekyan, A. Bieryla, L. Borsato, A. Brandeker, D. R. Ciardi, A. Collier Cameron, K. A. Collins, J. A. Egger, D. Gandolfi, M. J. Hooton, D. W. Latham, M. Lendl, E. C. Matthews, A. Tuson, S. Ulmer-Moll, A. Vanderburg, T. G. Wilson, C. Ziegler, Y. Alibert, R. Alonso, G. Anglada, L. Arnold, J. Asquier, D. Barrado Y Navascues, W. Baumjohann, T. Beck, A. A. Belinski, W. Benz, F. Biondi, I. Boisse, X. Bonfils, C. Broeg, L. A. Buchhave, T. Bárczy, S. C. C. Barros, J. Cabrera, C. Cardona Guillen, I. Carleo, A. Castro-González, S. Charnoz, J. Christiansen, P. Cortes-Zuleta, S. Csizmadia, S. Dalal, M. B. Davies, M. Deleuil, X. Delfosse, L. Delrez, B.-O. Demory, A. B. Dunlavey, D. Ehrenreich, A. Erikson, R. B. Fernandes, A. Fortier, T. Forveille, L. Fossati, M. Fridlund, M. Gillon, R. F. Goeke, M. V. Goliguzova, E. J. Gonzales, M. N. Günther, M. Güdel, N. Heidari, C. E. Henze, S. Howell, S. Hoyer, J. I. Frey, K. G. Isaak, J. M. Jenkins, F. Kiefer, L. Kiss, J. Korth, P. F. L. Maxted, J. Laskar, A. Lecavelier Des Etangs, C. Lovis, M. B. Lund, R. Luque, D. Magrin, J. M. Almenara, E. Martioli, M. Mecina, J. V. Medina, D. Moldovan, M. Morales-Calderón, G. Morello, C. Moutou, F. Murgas, Eric L.N. Jensen, V. Nascimbeni, G. Olofsson, R. Ottensamer, I. Pagano, G. Peter, G. Piotto, D. Pollacco, D. Queloz, R. Ragazzoni, N. Rando, H. Rauer, I. Ribas, G. Ricker, O. D. S. Demangeon, A. M. S. Smith, N. Santos, G. Scandariato, S. Seager, S. G. Sousa, M. Steller, G. M. Szabó, D. Ségransan, N. Thomas, S. Udry, B. Ulmer, V. Van Grootel, R. Vanderspek, N. Walton, J. N. Winn

Physics & Astronomy Faculty Works

HIP 9618 (HD 12572, TOI-1471, TIC 306263608) is a bright (G = 9.0 mag) solar analogue. TESS photometry revealed the star to have two candidate planets with radii of 3.9 ± 0.044 R⊕ (HIP 9618 b) and 3.343 ± 0.039 R⊕ (HIP 9618 c). While the 20.77291 d period of HIP 9618 b was measured unambiguously, HIP 9618 c showed only two transits separated by a 680-d gap in the time series, leaving many possibilities for the period. To solve this issue, CHEOPS performed targeted photometry of period aliases to attempt to recover the true period of planet c, …

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Delving Deep: A Population Of Extremely Dusty Dwarfs Observed By Jwst, L. Bisigello, G. Gandolfi, A. Grazian, G. Rodighiero, L. Costantin, A. R. Cooray, A. Feltre, C. Gruppioni, N. P. Hathi, Benne W. Holwerda, A. M. Koekemoer, R. A. Lucas, J. A. Newman, P. G. Pérez-González, L. Y. A. Yung, A. De La Vega, P. Arrabal Haro, M. B. Bagley, M. Dickinson, S. L. Finkelstein, J. S. Kartaltepe, C. Papovich, N. Pirzkal, S. Wilkins Aug 2023

Delving Deep: A Population Of Extremely Dusty Dwarfs Observed By Jwst, L. Bisigello, G. Gandolfi, A. Grazian, G. Rodighiero, L. Costantin, A. R. Cooray, A. Feltre, C. Gruppioni, N. P. Hathi, Benne W. Holwerda, A. M. Koekemoer, R. A. Lucas, J. A. Newman, P. G. Pérez-González, L. Y. A. Yung, A. De La Vega, P. Arrabal Haro, M. B. Bagley, M. Dickinson, S. L. Finkelstein, J. S. Kartaltepe, C. Papovich, N. Pirzkal, S. Wilkins

Faculty Scholarship

Aims. We take advantage of the NIRCam photometric observations available as part of the Cosmic Evolution Early Release Science survey (CEERS) to identify and analyse very red sources in an effort to discover very dusty star forming galaxies. Methods. We select red galaxies as objects with a S / N > 3 at 4.4 μm and a S / N < 2 in all JWST and HST filters at λ ≤ 2 μm, which corresponds to [ F 200 W ]−[ F 444 W ]> 1.2 considering CEERS depths. This selection is ideal to identify very dusty ( A V > 1 mag) galaxies with stellar masses between 10 6 and 10 10 M ⊙ at z < 5, more massive dusty galaxies at z = 5 − 18 and galaxies at z > 18 due to the Lyman absorption, independently of their dust …

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Open Data From The Third Observing Run Of Ligo, Virgo, Kagra, And Geo, R. Abbott, H. Abe, F. Acernese, Teviet Creighton, Mario C. Diaz, Francisco Llamas, Soma Mukherjee, Gaukhar Nurbek, Volker Quetschke, Wenhui Wang Aug 2023

Open Data From The Third Observing Run Of Ligo, Virgo, Kagra, And Geo, R. Abbott, H. Abe, F. Acernese, Teviet Creighton, Mario C. Diaz, Francisco Llamas, Soma Mukherjee, Gaukhar Nurbek, Volker Quetschke, Wenhui Wang

Physics and Astronomy Faculty Publications and Presentations

The global network of gravitational-wave observatories now includes five detectors, namely LIGO Hanford, LIGO Livingston, Virgo, KAGRA, and GEO 600. These detectors collected data during their third observing run, O3, composed of three phases: O3a starting in 2019 April and lasting six months, O3b starting in 2019 November and lasting five months, and O3GK starting in 2020 April and lasting two weeks. In this paper we describe these data and various other science products that can be freely accessed through the Gravitational Wave Open Science Center at https://gwosc.org. The main data set, consisting of the gravitational-wave strain time series …

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Computational And Experimental Study On Undoped And Er-Doped Lithium Tantalate Nanofluorescent Probes, Mkhitar A. Hobosyan, Andrea Pelayo Carvajal, Bhupendra B. Srivastava, Tamanna Zakia, Mohammed Jasim Uddin, Karen S. Martirosyan, Eric Rodriguez, Kofi Nketia Ackaah-Gyasi, Nicholas Dimakis Aug 2023

Computational And Experimental Study On Undoped And Er-Doped Lithium Tantalate Nanofluorescent Probes, Mkhitar A. Hobosyan, Andrea Pelayo Carvajal, Bhupendra B. Srivastava, Tamanna Zakia, Mohammed Jasim Uddin, Karen S. Martirosyan, Eric Rodriguez, Kofi Nketia Ackaah-Gyasi, Nicholas Dimakis

Physics and Astronomy Faculty Publications and Presentations

We present a combined density functional theory (DFT) and experimental work on lithium tantalate LiTaO3 (LT) and its Er-doped counterparts. We calculate the electronic and optical properties for both LT and LT:Er+3, with Er occupying either Li or Ta sites, at 4.167 mol%. The generalized gradient approximation (GGA) calculations show that the Er-4 f bands appear closer to the conduction band bottom and to the valance band top, for the first and second doped configurations, respectively. This agrees with changes in the imaginary part of the frequency dependent dielectric function between the doped configurations. There are striking differences between the …

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The Loneliest Galaxies In The Universe: A Gama And Galaxy Zoo Study On Void Galaxy Morphology, Lori E. Porter, Benne Holwerda, Sandor Kruk, Maritza Lara-López, Kevin A. Pimbblet, Christopher P A Henry, Sarah Casura, Lee S. Kelvin Jul 2023

The Loneliest Galaxies In The Universe: A Gama And Galaxy Zoo Study On Void Galaxy Morphology, Lori E. Porter, Benne Holwerda, Sandor Kruk, Maritza Lara-López, Kevin A. Pimbblet, Christopher P A Henry, Sarah Casura, Lee S. Kelvin

Faculty Scholarship

The large-scale structure of the Universe is comprised of galaxy filaments, tendrils, and voids. The majority of the Universe’s volume is taken up by these voids, which exist as underdense, but not empty, regions. The galaxies found inside these voids are expected to be some of the most isolated objects in the Universe. This study, using the Galaxy and Mass Assembly (GAMA) and Galaxy Zoo surveys, aims to investigate basic physical properties and morphology of void galaxies versus field (filament and tendril) galaxies. We use void galaxies with stellar masses (⁠M∗" role="presentation" style="box-sizing: border-box; margin: 0px; padding: 0px; border: 0px; …

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Advancing Our Understanding Of Martian Proton Aurora Through A Coordinated Multi-Model Comparison Campaign, Andrea C. G. Hughes, Michael Scott Chaffin, Edwin J. Mierkiewicz, Justin Deighan, Rebecca Jolitz, Esa Kallio, Guillaume Gronof, Valery I. Shematovich, Dmitry Bisikalo, Cyril L. Simon Wedlund, Jasper S. Halekas, Nicholas M. Schneider, Birgit Ritter, Zachary Girazian, Sonal Jain, Jean-Claude M. C. G´Erard, Bradley Michael Hegyi Jul 2023

Advancing Our Understanding Of Martian Proton Aurora Through A Coordinated Multi-Model Comparison Campaign, Andrea C. G. Hughes, Michael Scott Chaffin, Edwin J. Mierkiewicz, Justin Deighan, Rebecca Jolitz, Esa Kallio, Guillaume Gronof, Valery I. Shematovich, Dmitry Bisikalo, Cyril L. Simon Wedlund, Jasper S. Halekas, Nicholas M. Schneider, Birgit Ritter, Zachary Girazian, Sonal Jain, Jean-Claude M. C. G´Erard, Bradley Michael Hegyi

Publications

Proton aurora are the most commonly observed yet least studied type of aurora at Mars. In order to better understand the physics and driving processes of Martian proton aurora, we undertake a multi-model comparison campaign. We compare results from four different proton/hydrogen precipitation models with unique abilities to represent Martian proton aurora: Jolitz model (3-D Monte Carlo), Kallio model (3-D Monte Carlo), Bisikalo/Shematovich et al. model (1-D kinetic Monte Carlo), and Gronoff et al. model (1-D kinetic). This campaign is divided into two steps: an inter-model comparison and a data-model comparison. The inter-model comparison entails modeling five different representative cases …

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A Method For Calculating Lateral Surface Area Of Bistatic Radar Beam Overlap, James I. Murray, Fredrick A. Jenet Jul 2023

A Method For Calculating Lateral Surface Area Of Bistatic Radar Beam Overlap, James I. Murray, Fredrick A. Jenet

Physics and Astronomy Faculty Publications and Presentations

It has been shown that bistatic radars using radio telescopes as receivers can be used to increase the sensitivity of orbital debris measurements over traditional terrestrial monostatic radar. A method to calculate the lateral surface area of a bistatic radar is needed to evaluate the efficacy of a proposed bistatic radar configuration for orbital debris measurements. For over three decades, models of the orbital debris (OD) environment in low Earth orbit (LEO) have been developed to assess the risk posed by OD to spacecraft. While terrestrial radar measures debris 3 mm and larger and in situ measurements provide data for …

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What Is A Polygonal Impact Crater? A Proposed Framework Toward Quantifying Crater Shapes, Stuart J. Robbins, Jamie D. Riggs Jul 2023

What Is A Polygonal Impact Crater? A Proposed Framework Toward Quantifying Crater Shapes, Stuart J. Robbins, Jamie D. Riggs

College of Population Health Faculty Papers

Impact craters are used for a wide array of investigations of planetary surfaces. A crater form that is somewhat rare, forming only ∼10% of impact craters, is the polygonal impact crater (or PIC). These craters have been visually, manually identified as having at least two rim segments that are best represented as straight lines. Such straight lines or edges are most often used to infer details about the subsurface crust where faults control the structure of the crater cavity as it formed. The PIC literature is scant, but almost exclusively these craters are identified manually, and the potentially straight edges …

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Noise Analysis Of The Indian Pulsar Timing Array Data Release I, Aman Srivastava, Shantanu Desai, Neel Kolhe, Mayuresh Surnis, Bhal Chandra Joshi, Abhimanyu Susobhanan, Aurélien Chalumeau, Shinnosuke Hisano, Nobleson K, Raghav Girgaonkar Jul 2023

Noise Analysis Of The Indian Pulsar Timing Array Data Release I, Aman Srivastava, Shantanu Desai, Neel Kolhe, Mayuresh Surnis, Bhal Chandra Joshi, Abhimanyu Susobhanan, Aurélien Chalumeau, Shinnosuke Hisano, Nobleson K, Raghav Girgaonkar

Physics and Astronomy Faculty Publications and Presentations

The Indian Pulsar Timing Array (InPTA) collaboration has recently made its first official data release (DR1) for a sample of 14 pulsars using 3.5 years of uGMRT observations. We present the results of single-pulsar noise analysis for each of these 14 pulsars using the InPTA DR1. For this purpose, we consider white noise, achromatic red noise, dispersion measure (DM) variations, and scattering variations in our analysis. We apply Bayesian model selection to obtain the preferred noise models among these for each pulsar. For PSR J1600−3053, we find no evidence of DM and scattering variations, while for PSR J1909−3744, we find …

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Estimation Of The Kelvin–Helmholtz Unstable Boundary, Xuanye Ma Jul 2023

Estimation Of The Kelvin–Helmholtz Unstable Boundary, Xuanye Ma

Publications

The Kelvin–Helmholtz (KH) instability is one of the most important mechanisms of the viscous like interaction between the solar wind and the magnetosphere (MSP), which transport the mass, energy, momentum, and magnetic flux. Thus, it is important to examine whether the magnetopause boundary is KH unstable or not. Based on the KH onset conditions, this report proposes to use a matrix to identify the most KH unstable direction based on the in-situ measurements of the density, velocity, and magnetic field in the MSP and magneto sheath. The range of the KH unstable direction can be easily estimated based on the …

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Gama/Devils: Cosmic Star Formation And Agn Activity Over 12.5 Billion Years, Jordan C J D’Silva, Simon P. Driver, Claudia D P Lagos, Aaron S G Robotham, Sabine Bellstedt, Luke J M Davies, Jessica E. Thorne, Joss Bland-Hawthorn, Matias Bravo, Benne Holwerda, Steven Phillipps, Nick Seymour, Malgorzata Siudek, Rogier A. Windhorst Jul 2023

Gama/Devils: Cosmic Star Formation And Agn Activity Over 12.5 Billion Years, Jordan C J D’Silva, Simon P. Driver, Claudia D P Lagos, Aaron S G Robotham, Sabine Bellstedt, Luke J M Davies, Jessica E. Thorne, Joss Bland-Hawthorn, Matias Bravo, Benne Holwerda, Steven Phillipps, Nick Seymour, Malgorzata Siudek, Rogier A. Windhorst

Faculty Scholarship

We use the Galaxy and Mass Assembly (GAMA) and the Deep Extragalactic Visible Legacy Survey (DEVILS) observational data sets to calculate the cosmic star formation rate (SFR) and active galactic nuclei (AGN) bolometric luminosity history (CSFH/CAGNH) over the last 12.5 billion years. SFRs and AGN bolometric luminosities were derived using the spectral energy distribution fitting code ProSpect, which includes an AGN prescription to self consistently model the contribution from both AGN and stellar emission to the observed rest-frame ultra-violet to far-infrared photometry. We find that both the CSFH and CAGNH evolve similarly, rising in the early Universe up to a …

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Discovery Of Extraordinary X-Ray Emission From Magnetospheric Interaction In The Unique Binary Stellar System Ε Lupi, B. Das, V. Petit, Y. Nazé, M. F. Corcoran, David H. Cohen, A. Biswas, P. Chandra, A. David-Uraz, M. A. Leutenegger, C. Neiner, H. Pablo, E. Paunzen, M. E. Shultz, A. Ud-Doula, G. A. Wade Jul 2023

Discovery Of Extraordinary X-Ray Emission From Magnetospheric Interaction In The Unique Binary Stellar System Ε Lupi, B. Das, V. Petit, Y. Nazé, M. F. Corcoran, David H. Cohen, A. Biswas, P. Chandra, A. David-Uraz, M. A. Leutenegger, C. Neiner, H. Pablo, E. Paunzen, M. E. Shultz, A. Ud-Doula, G. A. Wade

Physics & Astronomy Faculty Works

We report detailed X-ray observations of the unique binary system ϵ Lupi, the only known short-period binary consisting of two magnetic early-type stars. The components have comparably strong, but anti-aligned magnetic fields. The orbital and magnetic properties of the system imply that the magnetospheres overlap at all orbital phases, suggesting the possibility of variable inter-star magnetospheric interaction due to the non-negligible eccentricity of the orbit. To investigate this effect, we observed the X-ray emission from ϵ Lupi, both near and away from periastron passage, using the Neutron Star Interior Composition Explorer mission (NICER) X-ray Telescope. We find that the system …

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Toi-2498 B: A Hot Bloated Super-Neptune Within The Neptune Desert, G. Frame, D. J. Armstrong, H. M. Cegla, J. Fernández Fernández, A. Osborn, V. Adibekyan, K. A. Collins, E. Delgado Mena, S. Giacalone, J. F. Kielkopf, N. C. Santos, S. G. Sousa, K. G. Stassun, C. Ziegler, D. R. Anderson, S. C. C. Barros, D. Bayliss, C. Briceño, D. M. Conti, C. D. Dressing, X. Dumusque, P. Figueira, W. Fong, S. Gill, F. Hawthorn, J. M. Jenkins, Eric L.N. Jensen, M. A. F. Keniger, D. W. Latham, N. Law, J. J. Lissauer, A. W. Mann, L. D. Nielsen, H. Osborn, M. Paegert, S. Seager, R. P. Schwarz, A. Shporer, G. Srdoc, P. A. Strøm, J. N. Winn, P. J. Wheatley Jul 2023

Toi-2498 B: A Hot Bloated Super-Neptune Within The Neptune Desert, G. Frame, D. J. Armstrong, H. M. Cegla, J. Fernández Fernández, A. Osborn, V. Adibekyan, K. A. Collins, E. Delgado Mena, S. Giacalone, J. F. Kielkopf, N. C. Santos, S. G. Sousa, K. G. Stassun, C. Ziegler, D. R. Anderson, S. C. C. Barros, D. Bayliss, C. Briceño, D. M. Conti, C. D. Dressing, X. Dumusque, P. Figueira, W. Fong, S. Gill, F. Hawthorn, J. M. Jenkins, Eric L.N. Jensen, M. A. F. Keniger, D. W. Latham, N. Law, J. J. Lissauer, A. W. Mann, L. D. Nielsen, H. Osborn, M. Paegert, S. Seager, R. P. Schwarz, A. Shporer, G. Srdoc, P. A. Strøm, J. N. Winn, P. J. Wheatley

Physics & Astronomy Faculty Works

We present the discovery and confirmation of a transiting hot bloated super-Neptune using photometry from the Transiting Exoplanet Survey Satellite (TESS) and the Las Cumbres Observatory Global Telescope (LCOGT) and radial velocity measurements from the High Accuracy Radial velocity Planet Searcher (HARPS). The host star TOI-2498 is a V = 11.2, G-type (Teff = 5905 ± 12 K) solar-like star with a mass of 1.12 ± 0.02 M⊙ and a radius of 1.26 ± 0.04 R⊙. The planet, TOI-2498 b, orbits the star with a period of 3.7 d, has a radius of …

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Dataset Of Optical And Electronic Properties For Mos Browzine Journal Cover 2-Graphene Vertical Heterostructures And Mos2-Graphene-Au Heterointerfaces, Sanju Gupta, Panagiota Pimenidou, Miguel Garcia, Shivanshi Das, Nicholas Dimakis Jun 2023

Dataset Of Optical And Electronic Properties For Mos Browzine Journal Cover 2-Graphene Vertical Heterostructures And Mos2-Graphene-Au Heterointerfaces, Sanju Gupta, Panagiota Pimenidou, Miguel Garcia, Shivanshi Das, Nicholas Dimakis

Physics and Astronomy Faculty Publications and Presentations

The computational and experimental data presented in this paper refer to the research article "First-Principles Calculations Integrated with Experimental Optical and Electronic Properties for MoS2-graphene Heterostructures and MoS2-graphene-Au Heterointerfaces". The computational data includes structural information, electronic and optical properties, and data to calculate the work functions for various molybdenum disulfide and graphene heterostructures and their heterointerfaces with gold. The optical properties calculations include the frequency-dependent dielectric function, the refractive index, the reflectivity, the extinction coefficient, and the energy loss function. These properties were calculated using the independent particle approximation (IPA). As for the experimental optoelectronic properties, we measured photoluminescence spectra …

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Bayesian Inference For The White Dwarf Initial-Final Mass Relation, Nathan Stein, Ted Von Hippel, David Van Dyk, Steven Degennaro, Elizabeth Jeffery, Bill Jefferys Jun 2023

Bayesian Inference For The White Dwarf Initial-Final Mass Relation, Nathan Stein, Ted Von Hippel, David Van Dyk, Steven Degennaro, Elizabeth Jeffery, Bill Jefferys

Publications

Stars lose mass as they age, and understanding mass loss is important for understanding stellar evolution. The initial-final mass relation (IFMR) is the relationship between a white dwarf’s initial mass on the main sequence and its final mass. We have developed a new method for fitting the IFMR based on a Bayesian analysis of photometric observations, combining deterministic models of stellar evolution in an internally coherent way. No mass data are used. Our method yields precise inferences (with uncertainties) for a parameterized linear IFMR. Our method can also return posterior distributions of white dwarf initial and final masses.

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Databases And Inter-Connectivity In Ground-Based Astronomy, Ted Von Hippel, C. M. Mountain Jun 2023

Databases And Inter-Connectivity In Ground-Based Astronomy, Ted Von Hippel, C. M. Mountain

Publications

Optical and infrared ground-based astronomy is undergoing a renaissance. Advances in material technology, system modeling, and the ability to correct atmospheric distortions in real time have produced a new generation of powerful, large telescopes. An equally profound revolution stems from the availability of large observational databases that span the electromagnetic spectrum. The increased use of such databases as well as the need to operate the new telescopes efficiently requires the development of a National or International Virtual Observatory to set standards for astronomical database formats, data quality assurance, and access protocols, and also to provide all-inclusive centers for data products.

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Galaxy And Mass Assembly (Gama): Comparing Visually And Spectroscopically Identified Galaxy Merger Samples, Alice Desmons, Sarah Brough, Cristina Martínez-Lombilla, Roberto De Propris, Benne Holwerda, Ángel R. López-Sánchez Jun 2023

Galaxy And Mass Assembly (Gama): Comparing Visually And Spectroscopically Identified Galaxy Merger Samples, Alice Desmons, Sarah Brough, Cristina Martínez-Lombilla, Roberto De Propris, Benne Holwerda, Ángel R. López-Sánchez

Faculty Scholarship

We conduct a comparison of the merging galaxy populations detected by a sample of visual identification of tidal features around galaxies as well as spectroscopically detected close pairs of galaxies to determine whether our method of selecting merging galaxies biases our understanding of galaxy interactions. Our volume-limited parent sample consists of 852 galaxies from the Galaxy And Mass Assembly (GAMA) survey in the redshift range 0.04 ≤ z ≤ 0.20 and stellar mass range 9.50 ≤ log 10(M⋆/M⊙)≤ 11.0" role="presentation" style="box-sizing: border-box; margin: 0px; padding: 0px; border: 0px; font-variant: inherit; font-stretch: inherit; line-height: normal; font-family: inherit; font-optical-sizing: inherit; font-kerning: inherit; …

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Constraints On The Cosmic Expansion History From Gwtc–3, R. Abbott, H. Abe, F. Acernese, K. Ackley, N. Adhikari, M. G. Benjamin, Teviet Creighton, Mario C. Diaz, F. Llamas, Soma Mukherjee, Gaukhar Nurbek, Volker Quetschke, Wenhui Wang Jun 2023

Constraints On The Cosmic Expansion History From Gwtc–3, R. Abbott, H. Abe, F. Acernese, K. Ackley, N. Adhikari, M. G. Benjamin, Teviet Creighton, Mario C. Diaz, F. Llamas, Soma Mukherjee, Gaukhar Nurbek, Volker Quetschke, Wenhui Wang

Physics and Astronomy Faculty Publications and Presentations

We use 47 gravitational wave sources from the Third LIGO–Virgo–Kamioka Gravitational Wave Detector Gravitational Wave Transient Catalog (GWTC–3) to estimate the Hubble parameter H(z), including its current value, the Hubble constant H0. Each gravitational wave (GW) signal provides the luminosity distance to the source, and we estimate the corresponding redshift using two methods: the redshifted masses and a galaxy catalog. Using the binary black hole (BBH) redshifted masses, we simultaneously infer the source mass distribution and H(z). The source mass distribution displays a peak around 34 M⊙, followed by a drop-off. Assuming …

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The Giant Accreting Protoplanet Survey (Gaplanets)—Results From A 6 Yr Campaign To Image Accreting Protoplanets, Katherine B. Follette, Laird M. Close, Jared R. Males, Kimberly Ward-Duong, William O. Balmer, Jéa Adams Redai, Julio Morales, Catherine Sarosi, Beck Dacus, Robert J. De Rosa, Fernando Garcia Toro, Clare Leonard, Bruce Macintosh, Katie M. Morzinski, Wyatt Mullen, Joseph Palmo, Raymond Nzaba Saitoti, Elijah Spiro, Helena Treiber, Kevin Wagner, Jason Wang, David Wang, Alex Watson, Alycia J. Weinberger Jun 2023

The Giant Accreting Protoplanet Survey (Gaplanets)—Results From A 6 Yr Campaign To Image Accreting Protoplanets, Katherine B. Follette, Laird M. Close, Jared R. Males, Kimberly Ward-Duong, William O. Balmer, Jéa Adams Redai, Julio Morales, Catherine Sarosi, Beck Dacus, Robert J. De Rosa, Fernando Garcia Toro, Clare Leonard, Bruce Macintosh, Katie M. Morzinski, Wyatt Mullen, Joseph Palmo, Raymond Nzaba Saitoti, Elijah Spiro, Helena Treiber, Kevin Wagner, Jason Wang, David Wang, Alex Watson, Alycia J. Weinberger

Astronomy: Faculty Publications

Accreting protoplanets are windows into planet formation processes, and high-contrast differential imaging is an effective way to identify them. We report results from the Giant Accreting Protoplanet Survey (GAPlanetS), which collected Hα differential imagery of 14 transitional disk host stars with the Magellan Adaptive Optics System. To address the twin challenges of morphological complexity and point-spread function instability, GAPlanetS required novel approaches for frame selection and optimization of the Karhounen-Loéve Image Processing algorithm pyKLIP. We detect one new candidate, CS Cha “c,” at a separation of 68 mas and a modest Δmag of 2.3. We recover the HD 142527 B …

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Exceptional Point Based Lattice Gyroscopes, Masoumeh Izadparast, Gururaj V. Naik, Henry O. Everitt, Hamidreza Ramezani Jun 2023

Exceptional Point Based Lattice Gyroscopes, Masoumeh Izadparast, Gururaj V. Naik, Henry O. Everitt, Hamidreza Ramezani

Physics and Astronomy Faculty Publications and Presentations

Ring laser gyroscopes (RLGs) based on non-Hermitian exceptional points (EPs) have garnered much recent interest due to their exceptional sensitivity. Such gyroscopes typically consist of two-ring laser resonators, one with loss and one with an equal amount of optical gain. The coupling strength between these ring resonators is a key parameter determining the sensitivity of EP-based RLGs. Here we explore how the exceptional sensitivity demonstrated in this coupled dimer may be further enhanced by adding more dimers in an array. Specifically, we propose two types of ring laser gyroscope lattice arrays, each composed of N coupled dimers arrayed serially or …

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Photon Propagation In Magnetized Dense Quark Matter. A Possible Solution For The Missing Pulsar Problem., Efrain J. Ferrer Jun 2023

Photon Propagation In Magnetized Dense Quark Matter. A Possible Solution For The Missing Pulsar Problem., Efrain J. Ferrer

Physics and Astronomy Faculty Publications and Presentations

In this paper it is reviewed the topological properties and possible astrophysical consequences of a spatially inhomogeneous phase of quark matter, known as the Magnetic Dual Chiral Density Wave (MDCDW) phase, that can exist at intermediate baryon density in the presence of a magnetic field. Going beyond mean-field approximation, it is shown how linearly polarized electromagnetic waves penetrating the MDCDW medium can mix with the phonon fluctuations to give rise to two hybridized modes of propagation called as axion polaritons because of their similarity with certain modes found in condensed matter for topological magnetic insulators. The formation of axion polaritons …

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Can The Mdcdw Condensate Withstand The Heat Of A Cold Neutron Star?, William Gyory Jun 2023

Can The Mdcdw Condensate Withstand The Heat Of A Cold Neutron Star?, William Gyory

Physics and Astronomy Faculty Publications and Presentations

The correct description of strongly interacting matter at low temperatures and moderately high densities—in particular the conditions realized inside neutron stars—is still unknown. We review some recent results on the magnetic dual chiral density wave (MDCDW) phase, a candidate phase of quark matter for this region of the QCD phase diagram. We highlight the effects of magnetic fields and temperature on the condensate, which can be explored using a high-order Ginzburg-Landau (GL) expansion. We also explain how the condensate's nontrivial topology, which arises due to the asymmetry in the lowest Landau level modes, affects its physical properties. Finally, we comment …

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Multimessenger Observations Of Double Neutron Stars In The Galactic Disk With Gravitational And Radio Waves, Wen-Fan Feng, Jie-Wen Chen, Yan Wang, Soumya D. Mohanty, Yong Shao May 2023

Multimessenger Observations Of Double Neutron Stars In The Galactic Disk With Gravitational And Radio Waves, Wen-Fan Feng, Jie-Wen Chen, Yan Wang, Soumya D. Mohanty, Yong Shao

Physics and Astronomy Faculty Publications and Presentations

We evaluate the prospects for radio follow-up of the double neutron stars (DNSs) in the Galactic disk that could be detected through future space-borne gravitational wave (GW) detectors. We first simulate the DNS population in the Galactic disk that is accessible to space-borne GW detectors according to the merger rate from recent LIGO results. Using the inspiraling waveform for the eccentric binary, the average number of the DNSs detectable by TianQin (TQ), LISA, and TQ+LISA are 217, 368, and 429, respectively. For the joint GW detection of TQ+LISA, the forecasted parameter estimation accuracies, based on the Fisher information matrix, for …

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Observation Of Robust Zero Energy Extended States, J. Ferdous, Cem Yuce, Andrea Alu, Hamidreza Ramezani May 2023

Observation Of Robust Zero Energy Extended States, J. Ferdous, Cem Yuce, Andrea Alu, Hamidreza Ramezani

Physics and Astronomy Faculty Publications and Presentations

Topological edge states arise at the interface of two topologically distinct structures and have two distinct features: they are localized and robust against symmetry protecting disorder. On the other hand, conventional transport in one dimension is associated with extended states, which typically do not have topological robustness. In this letter, using lossy coupled resonators in one dimension, we demonstrate both theoretically and experimentally the existence of robust states residing in the bulk. We show that they are unusually robust against disorders in coupling between adjacent sites and losses. Our work paves the way to a different form of robust transport …

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A Stochastic Search For Intermittent Gravitational-Wave Backgrounds, Jessica Lawrence, Kevin Turbang, Andrew Matas, Arianna I. Renzini, Nick Van Remortel, Joseph D. Romano May 2023

A Stochastic Search For Intermittent Gravitational-Wave Backgrounds, Jessica Lawrence, Kevin Turbang, Andrew Matas, Arianna I. Renzini, Nick Van Remortel, Joseph D. Romano

Physics and Astronomy Faculty Publications and Presentations

A likely source of a gravitational-wave background (GWB) in the frequency band of the Advanced LIGO, Virgo, and KAGRA detectors is the superposition of signals from the population of unresolvable stellar-mass binary-black-hole (BBH) mergers throughout the Universe. Since the duration of a BBH merger in band (similar to 1 s) is much shorter than the expected separation between neighboring mergers (similar to 103 s), the observed signal will be "popcornlike" or intermittent with duty cycles of order 10-3. However, the standard cross-correlation search for stochastic GWBs currently performed by the LIGO-Virgo-KAGRA Collaboration is based on a continuous-Gaussian signal model, which …

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Glitch Subtraction From Gravitational Wave Data Using Adaptive Spline Fitting, Soumya D. Mohanty, Mohammad A. T. Chowdhury May 2023

Glitch Subtraction From Gravitational Wave Data Using Adaptive Spline Fitting, Soumya D. Mohanty, Mohammad A. T. Chowdhury

Physics and Astronomy Faculty Publications and Presentations

Transient signals of instrumental and environmental origins ("glitches") in gravitational wave data elevate the false alarm rate of searches for astrophysical signals and reduce their sensitivity. Glitches that directly overlap astrophysical signals hinder their detection and worsen parameter estimation errors. As the fraction of data occupied by detectable astrophysical signals will be higher in next generation detectors, such problematic overlaps could become more frequent. These adverse effects of glitches can be mitigated by estimating and subtracting them out from the data, but their unpredictable waveforms and large morphological diversity pose a challenge. Subtraction of glitches using data from auxiliary sensors …

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Transit Photometry Of Multiple Exoplanet Watch Targets, Jonah Becken May 2023

Transit Photometry Of Multiple Exoplanet Watch Targets, Jonah Becken

Celebrating Scholarship and Creativity Day (2018-)

Since 1995 exoplanet research has increase dramatically, as a result it is more important than ever to precisely know the dates and times of future transits for repeated observations of a target. NASA’s Exoplanet Watch database and accompanying light curve producing code EXOTIC have the goal of allowing small observatories across the world help find future transits. Under these objective observations of known exoplanet transits where made, using the Saint John’s University observatory, to find the transit midpoint, the ratio of the planet radius and the solar radius, and the period. Using these values, the confirmation that a transit happened …

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Seasonal And Diurnal Variations Of Kelvin-Helmholtz Instability At Terrestrial Magnetopause, S. Kavosi, J. Raeder, Jay R. Johnson, K. Nykyri, C. J. Farrugia May 2023

Seasonal And Diurnal Variations Of Kelvin-Helmholtz Instability At Terrestrial Magnetopause, S. Kavosi, J. Raeder, Jay R. Johnson, K. Nykyri, C. J. Farrugia

Faculty Publications

Kelvin-Helmholtz Instability is ubiquitous at Earth’s magnetopause and plays an important role in plasma entry into the magnetosphere during northward interplanetary magnetic fields. Here, using one solar cycle of data from NASA THEMIS (Time History of Events and Macro scale Interactions during Substorms) and MMS (Magnetospheric Multiscale) missions, we found that KHI occurrence rates show seasonal and diurnal variations with the rate being high near the equinoxes and low near the solstices. The instability depends directly on the Earth’s dipole tilt angle. The tilt toward or away from the Sun explains most of the seasonal and diurnal variations, while the …

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Red Riding On Hood: Exploring How Galaxy Colour Depends On Environment, Pankaj C. Bhambhani, Ivan K. Baldry, Sarah Brough, Alexander D. Hill, M A. Lara-Lopez, J Loveday, Benne Holwerda May 2023

Red Riding On Hood: Exploring How Galaxy Colour Depends On Environment, Pankaj C. Bhambhani, Ivan K. Baldry, Sarah Brough, Alexander D. Hill, M A. Lara-Lopez, J Loveday, Benne Holwerda

Faculty Scholarship

Galaxy populations are known to exhibit a strong colour bimodality, corresponding to blue star-forming and red quiescent subpopulations. The relative abundance of the two populations has been found to vary with stellar mass and environment. In this paper, we explore the effect of environment considering different types of measurements. We choose a sample of 49 911 galaxies with 0.05 < z < 0.18 from the Galaxy And Mass Assembly survey. We study the dependence of the fraction of red galaxies on different measures of the local environment as well as the large-scale `geometric’ environment defined by density gradients in the surrounding cosmic web. We find that the red galaxy fraction varies with the environment at fixed stellar mass. The red fraction depends more strongly on local environmental measures than on large-scale geometric environment measures. By comparing the different environmental densities, we show that no density measurement fully explains the observed environmental red fraction variation, suggesting the different measures of environmental density contain different information. We test whether the local environmental measures, when combined together, can explain all the observed environmental red fraction variation. The geometric environment has a small residual effect, and this effect is larger for voids than any other type of geometric environment. This could provide a test of the physics applied to cosmological-scale galaxy evolution simulations as it combines large-scale effects with local environmental impact.

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