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Articles 451 - 480 of 9199

Full-Text Articles in Physical Sciences and Mathematics

Deciphering Surfaces Of Trans-Neptunian And Kuiper Belt Objects Using Radiative Scattering Models, Machine Learning, And Laboratory Experiments, Al Emran Dec 2022

Deciphering Surfaces Of Trans-Neptunian And Kuiper Belt Objects Using Radiative Scattering Models, Machine Learning, And Laboratory Experiments, Al Emran

Graduate Theses and Dissertations

Decoding surface-atmospheric interactions and volatile transport mechanisms on trans-Neptunian objects (TNOs) and Kuiper Belt objects (KBOs) involves an in-depth understanding of physical and thermal properties and spatial distribution of surface constituents – nitrogen (N2), methane (CH4), carbon monoxide (CO), and water (H2O) ices. This thesis implements a combination of radiative scattering models, machine learning techniques, and laboratory experiments to investigate the uncertainties in grain size estimation of ices, the spatial distribution of surface compositions on Pluto, and the thermal properties of volatiles found on TNOs and KBOs. Radiative scattering models (Mie theory and Hapke approximations) were used to compare single …

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Dataset For Electronic And Optical Properties Of Y2o2s And Er Dopped Y2o2s Calculated Using Density Functional Theory And Simulated X-Ray Near Edge Spectra, N. Dimakis, Eric Baldemar Rodriguez Jr., Kofi Nketia Ackaah-Gyasi, Madhab Pokhrel Dec 2022

Dataset For Electronic And Optical Properties Of Y2o2s And Er Dopped Y2o2s Calculated Using Density Functional Theory And Simulated X-Ray Near Edge Spectra, N. Dimakis, Eric Baldemar Rodriguez Jr., Kofi Nketia Ackaah-Gyasi, Madhab Pokhrel

Physics and Astronomy Faculty Publications and Presentations

The computational data presented in this paper refer to the research article “Optical properties and simulated x-ray near edge spectra for Y2O2S and Er doped Y2O2S”. We present the data used to calculate the structural, electronic, and optical properties of the Y2O2S and its Er+3 doped counterparts at various concentrations using density functional theory (DFT) and simulated X-ray near edge (XANES) spectra. We report electronic information from DFT and DFT+U generated from the Vienna Ab initio Simulation Package (VASP) using PAW pseudopotentials. We also report VASP calculated optical properties for the host Y2O2S using the independent particle approximation (IPA), the …

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Investigating The O’Connell Effect In Kepler Eclipsing Binaries, Matthew Frederick Knote Dec 2022

Investigating The O’Connell Effect In Kepler Eclipsing Binaries, Matthew Frederick Knote

Theses and Dissertations

The O’Connell effect – the presence of unequal maxima in eclipsing binaries – remains an unsolved riddle in the study of close binary systems. The Kepler space telescope produced high precision photometry of nearly 3,000 eclipsing binary systems, providing a unique opportunity to study the O’Connell effect in a large sample and in greater detail than in previous studies. I have characterized the observational properties – including temperature, luminosity, and eclipse depth – of a set of 212 systems (7.3% of Kepler eclipsing binaries) that display a maxima flux difference of at least 1%, representing the largest sample of O’Connell …

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Transient Sources And How To Study Them: Selected Topics In Multi-Messenger Astronomy, Jiawei Luo Dec 2022

Transient Sources And How To Study Them: Selected Topics In Multi-Messenger Astronomy, Jiawei Luo

UNLV Theses, Dissertations, Professional Papers, and Capstones

The discovery of cosmic neutrino flux by IceCube, and the multi-messenger observations of gravitational event GW170817 ushered in the era of multi-messenger astronomy. Since the Universe itself is a natural laboratory, multi-messenger astronomy can help us study the most extreme physics processes in great detail. In this dissertation, we touch on some of the currently unanswered questions involving different types of transient sources and different “messengers” of multi-messenger astronomy. We employ a variety of analysis methods, including machine learning, a method that has not yet been widely adopted in astronomy but is rapidly gaining momentum.We start this dissertation with Chapter …

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Boost The Lead Conversion Efficiency For The Synthesis Of Colloidal 2d Pbs Nanosheets, Tharaka Mds Weeraddana, Adam Roach, Shashini M. Premathilaka, Yiteng Tang, Jordan Fox, Liangfeng Sun Nov 2022

Boost The Lead Conversion Efficiency For The Synthesis Of Colloidal 2d Pbs Nanosheets, Tharaka Mds Weeraddana, Adam Roach, Shashini M. Premathilaka, Yiteng Tang, Jordan Fox, Liangfeng Sun

Physics and Astronomy Faculty Publications

In the synthesis of colloidal PbS nanosheets, the supernatant of the reaction solution is reused to boost the lead conversion efficiency. It doubles the conversion efficiency of the lead precursors to the PbS nanosheets. The nanosheets synthesized by reusing the supernatant have similar morphology, nearly identical thickness, and optical properties as the original ones, confirmed by transmission electron microscopy, X-ray diffraction, and photoluminescence spectroscopy. This method reduces the toxic Pb-containing waste during the synthesis, a step toward the green and scalable synthesis of colloidal 2D PbS nanosheets.

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All-Sky Search For Continuous Gravitational Waves From Isolated Neutron Stars Using Advanced Ligo And Advanced Virgo O3 Data, R. Abbott, H. Abe, M. G. Benjamin, Teviet Creighton, Mario C. Diaz, Francisco Llamas, Soma Mukherjee, Gaukhar Nurbek, Volker Quetschke, Wenhui Wang Nov 2022

All-Sky Search For Continuous Gravitational Waves From Isolated Neutron Stars Using Advanced Ligo And Advanced Virgo O3 Data, R. Abbott, H. Abe, M. G. Benjamin, Teviet Creighton, Mario C. Diaz, Francisco Llamas, Soma Mukherjee, Gaukhar Nurbek, Volker Quetschke, Wenhui Wang

Physics and Astronomy Faculty Publications and Presentations

We present results of an all-sky search for continuous gravitational waves which can be produced by spinning neutron stars with an asymmetry around their rotation axis, using data from the third observing run of the Advanced LIGO and Advanced Virgo detectors. Four different analysis methods are used to search in a gravitational-wave frequency band from 10 to 2048 Hz and a first frequency derivative from −10−8 to 10−9  Hz/s. No statistically significant periodic gravitational-wave signal is observed by any of the four searches. As a result, upper limits on the gravitational-wave strain amplitude h0 are calculated. The best upper limits …

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Wallaby Pilot Survey: Hi Gas Kinematics Of Galaxy Pairs In Cluster Environment, Shin-Jeong Kim, Minsu Kim, Hye-Jin Park, Shinna Kim, Bigiel Frank, Helga Denes, Bi-Qing For, Peter Kamphuis, Se-Heon Oh, Benne Holwerda, Kristen Mcquinn, Juan Madrid, Ahmed Elagali, Gerhardt R. Meurer, Kristine Spekkens, Lister Staveley-Smith, Barbara Catinella, Nathan Deg, Karen Lee-Waddell, Jing Wang, Lourdes Verdes-Montenegro, Ivy Wong, Jonghwan Rhee Nov 2022

Wallaby Pilot Survey: Hi Gas Kinematics Of Galaxy Pairs In Cluster Environment, Shin-Jeong Kim, Minsu Kim, Hye-Jin Park, Shinna Kim, Bigiel Frank, Helga Denes, Bi-Qing For, Peter Kamphuis, Se-Heon Oh, Benne Holwerda, Kristen Mcquinn, Juan Madrid, Ahmed Elagali, Gerhardt R. Meurer, Kristine Spekkens, Lister Staveley-Smith, Barbara Catinella, Nathan Deg, Karen Lee-Waddell, Jing Wang, Lourdes Verdes-Montenegro, Ivy Wong, Jonghwan Rhee

Faculty and Staff Scholarship

We examine the H I gas kinematics of galaxy pairs in two clusters and a group using Australian Square Kilometre Array Pathfinder (ASKAP) WALLABY pilot survey observations. We compare the H I properties of galaxy pair candidates in the Hydra I and Norma clusters, and the NGC 4636 group, with those of non-paired control galaxies selected in the same fields. We perform H I profile decomposition of the sample galaxies using a tool, BAYGAUD which allows us to de-blend a line-of-sight velocity profile with an optimal number of Gaussian components. We construct H I super-profiles of the sample galaxies via …

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Galaxy And Mass Assembly (Gama): Extended Intragroup Light In A Group At Z = 0.2 From Deep Hyper Suprime-Cam Images, Cristina Martínez-Lombilla, Sarah Brough, Mireia Montes, Roberto Baena-Gallé, Mohammad Akhlaghi, Raúl Infante-Sainz, Simon P. Driver, Benne W. Holwerda, Kevin A. Pimbblet, Aaron S G Robotham Nov 2022

Galaxy And Mass Assembly (Gama): Extended Intragroup Light In A Group At Z = 0.2 From Deep Hyper Suprime-Cam Images, Cristina Martínez-Lombilla, Sarah Brough, Mireia Montes, Roberto Baena-Gallé, Mohammad Akhlaghi, Raúl Infante-Sainz, Simon P. Driver, Benne W. Holwerda, Kevin A. Pimbblet, Aaron S G Robotham

Faculty and Staff Scholarship

We present a pilot study to assess the potential of Hyper Suprime-Cam Public Data Release 2 (HSC-PDR2) images for the analysis of extended faint structures within groups of galaxies. We examine the intragroup light (IGL) of the group 400138 (Mdyn = 1.3 ± 0.5 × 1013 M⊙, z ∼ 0.2) from the Galaxy And Mass Assembly (GAMA) survey using Hyper Suprime-Cam Subaru Strategic Program Public Data Release 2 (HSC-SSP PDR2) images in g, r, and i bands. We present the most extended IGL measurement to date, reaching down to μglim=30.76" role="presentation" style="box-sizing: border-box; margin: 0px; …

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Characteristics Of Kelvin-Helmholtz Waves As Observed By The Mms From September 2015 To June 2017, Katariina Nykyri, Xuanye Ma, Rachel C. Rice Nov 2022

Characteristics Of Kelvin-Helmholtz Waves As Observed By The Mms From September 2015 To June 2017, Katariina Nykyri, Xuanye Ma, Rachel C. Rice

Publications

The Magnetospheric Multiscale (MMS) mission has presented a new opportunity to study the fine scale structures and phenomena of Earth’s magnetosphere, including cross scale processes associated with the Kelvin-Helmholtz Instability (KHI). We present an overview of 19 MMS observations of the KHI from September 2015 to June 2017. Unitless growth rates and unstable solid angles for each of the 19 events were calculated using 5 techniques to automatically detect plasma regions on either side of the magnetopause boundary. There was no apparent correlation between solar wind conditions during the KHI and its growth rate and unstable solid angle, though we …

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Electromagnetism In Quark Matter At Intermediate Densities, Efrain J. Ferrer Nov 2022

Electromagnetism In Quark Matter At Intermediate Densities, Efrain J. Ferrer

Physics and Astronomy Faculty Publications and Presentations

Several anomalous electromagnetic effects that can take place in quark matter at low temperatures and intermediate densities will be discussed. The anomalous transport properties of the spatially inhomogeneous phase of quark matter known as the Magnetic Dual Chiral Density Wave (MDCDW) phase will be reviewed. Going beyond mean-field approximation, it will be shown how linearly polarized electromagnetic waves that penetrate the MDCDW medium mix with the phonon fluctuations to give rise to two hybridized modes of propagation called axion polaritons. Finally, some possible implications of these results for the astrophysics of neutron stars will be indicated.

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Resolving Galactic Binaries Using A Network Of Space-Borne Gravitational Wave Detectors, Xue-Hao Zhang, Shao-Dong Zhao, Soumya D. Mohanty, Yu-Xiao Liu Nov 2022

Resolving Galactic Binaries Using A Network Of Space-Borne Gravitational Wave Detectors, Xue-Hao Zhang, Shao-Dong Zhao, Soumya D. Mohanty, Yu-Xiao Liu

Physics and Astronomy Faculty Publications and Presentations

Extracting gravitational wave (GW) signals from individual Galactic binaries (GBs) against their self-generated confusion noise is a key data analysis challenge for space-borne detectors operating in the ≈0.1 to ≈10  mHz range. Given the likely prospect that there will be multiple such detectors, namely Laser Interferometer Space Antenna (LISA), Taiji, and Tianqin, with overlapping operational periods in the next decade, it is important to examine the extent to which the joint analysis of their data can benefit GB resolution and parameter estimation. To investigate this, we use realistic simulated LISA and Taiji data containing the set of 30×106 GBs used …

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All-Sky Search For Short Gravitational-Wave Bursts In The Third Advanced Ligo And Advanced Virgo Run, Ligo Scientific Collaboration, Virgo Collaboration, Kagra Collaboration, Tiffany Z. Summerscales Nov 2022

All-Sky Search For Short Gravitational-Wave Bursts In The Third Advanced Ligo And Advanced Virgo Run, Ligo Scientific Collaboration, Virgo Collaboration, Kagra Collaboration, Tiffany Z. Summerscales

Faculty Publications

After the detection of gravitational waves from compact binary coalescences, the search for transient gravitational-wave signals with less well-defined waveforms for which matched filtering is not well suited is one of the frontiers for gravitational-wave astronomy. Broadly classified into “short” ≲1  s and “long” ≳1  s duration signals, these signals are expected from a variety of astrophysical processes, including non-axisymmetric deformations in magnetars or eccentric binary black hole coalescences. In this work, we present a search for long-duration gravitational-wave transients from Advanced LIGO and Advanced Virgo’s third observing run from April 2019 to March 2020. For this search, we use …

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Devils: Cosmic Evolution Of Sed-Derived Metallicities And Their Connection To Star Formation Histories, Jessica E. Thorne, Aaron S G Robotham, Sabine Bellstedt, Luke J M Davies, Robin H W Cook, Luca Cortese, Benne Holwerda, Steven Phillipps, Malgorzata Siudek Nov 2022

Devils: Cosmic Evolution Of Sed-Derived Metallicities And Their Connection To Star Formation Histories, Jessica E. Thorne, Aaron S G Robotham, Sabine Bellstedt, Luke J M Davies, Robin H W Cook, Luca Cortese, Benne Holwerda, Steven Phillipps, Malgorzata Siudek

Faculty and Staff Scholarship

Gas-phase metallicities of galaxies are typically measured through auroral or nebular emission lines, but metallicity also leaves an imprint on the overall spectral energy distribution (SED) of a galaxy and can be estimated through SED fitting. We use the PROSPECT SED fitting code with a flexible parametric star formation history and an evolving metallicity history to self-consistently measure metallicities, stellar mass, and other galaxy properties for 90 000 galaxies from the Deep Extragalactic VIsible Legacy Survey (DEVILS) and Galaxy and Mass Assembly (GAMA) survey. We use these to trace the evolution of the mass–metallicity relation (MZR) and show that the …

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Wallaby Pre-Pilot And Pilot Survey: The Tully Fisher Relation In Eridanus, Hydra, Norma And Ngc4636 Fields, Helene Courtois, Alexandra Dupuy, Kristen Mcquinn, Lister Staveley-Smith, Danail Obreschkow, Edward Taylor, Benne Holwerda, Cullan Howlett, Frank Bigiel, Daniel Pomarede, Bi-Qing For, Tao Hong, Dane Kleiner, Thomas Jarrett, Ivy Wong, Jonghwan Rhee, Albert Bosma, Khaled Said, Tamara Davis, Igor Karachentsev, Matthew Colless, Renee Kraan-Korteweg, Nathan Deg, Kristine Spekkens, Karen Lee-Waddell, Jing Wang, Gerhardt R. Meurer Nov 2022

Wallaby Pre-Pilot And Pilot Survey: The Tully Fisher Relation In Eridanus, Hydra, Norma And Ngc4636 Fields, Helene Courtois, Alexandra Dupuy, Kristen Mcquinn, Lister Staveley-Smith, Danail Obreschkow, Edward Taylor, Benne Holwerda, Cullan Howlett, Frank Bigiel, Daniel Pomarede, Bi-Qing For, Tao Hong, Dane Kleiner, Thomas Jarrett, Ivy Wong, Jonghwan Rhee, Albert Bosma, Khaled Said, Tamara Davis, Igor Karachentsev, Matthew Colless, Renee Kraan-Korteweg, Nathan Deg, Kristine Spekkens, Karen Lee-Waddell, Jing Wang, Gerhardt R. Meurer

Faculty and Staff Scholarship

The WALLABY pilot survey has been conducted using the Australian SKA Pathfinder (ASKAP). The integrated 21-cm HI line spectra are formed in a very different manner compared to usual single-dish spectra Tully-Fisher measurements. It is thus extremely important to ensure that slight differences (e.g. biases due to missing flux) are quantified and understood in order to maximise the use of the large amount of data becoming available soon. This article is based on four fields for which the data are scientifically interesting by themselves. The pilot data discussed here consist of 614 galaxy spectra at a rest wavelength of 21cm. …

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Iterative Time-Domain Method For Resolving Multiple Gravitational Wave Sources In Pulsar Timing Array Data, Yi Qian Qian, Soumya D. Mohanty, Yan Wang Nov 2022

Iterative Time-Domain Method For Resolving Multiple Gravitational Wave Sources In Pulsar Timing Array Data, Yi Qian Qian, Soumya D. Mohanty, Yan Wang

Physics and Astronomy Faculty Publications and Presentations

The sensitivity of ongoing searches for gravitational wave (GW) sources in the ultra-low-frequency regime (10(-9) Hz to 10(-7) Hz) using pulsar timing arrays (PTAs) will continue to increase in the future as more well-timed pulsars are added to the arrays. It is expected that next-generation radio telescopes, namely, the Five-Hundred-Meter Aperture Spherical Radio Telescope (FAST) and the Square Kilometer Array (SKA), will grow the number of well-timed pulsars to O(10(3)). The higher sensitivity will result in greater distance reach for GW sources, uncovering multiple resolvable GW sources in addition to an unresolved population. Data analysis techniques that can search for …

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Galaxy And Mass Assembly: Galaxy Morphology In The Green Valley, Prominent Rings, And Looser Spiral Arms, Dominic Smith, Lutz Haberzettl, L E. Porter, Ren Porter-Temple, Christopher P A Henry, Benne Holwerda, Á R. López-Sánchez, Steven Phillipps, Alister W. Graham, Sarah Brough, Kevin A. Pimbblet, Jochen Liske, Lee S. Kelvin, Clayton D. Robertson, Wade Roemer, Michael Walmsley, David O’Ryan, Tobias Géron Nov 2022

Galaxy And Mass Assembly: Galaxy Morphology In The Green Valley, Prominent Rings, And Looser Spiral Arms, Dominic Smith, Lutz Haberzettl, L E. Porter, Ren Porter-Temple, Christopher P A Henry, Benne Holwerda, Á R. López-Sánchez, Steven Phillipps, Alister W. Graham, Sarah Brough, Kevin A. Pimbblet, Jochen Liske, Lee S. Kelvin, Clayton D. Robertson, Wade Roemer, Michael Walmsley, David O’Ryan, Tobias Géron

Faculty and Staff Scholarship

Galaxies broadly fall into two categories: star-forming (blue) galaxies and quiescent (red) galaxies. In between, one finds the less populated “green valley". Some of these galaxies are suspected to be in the process of ceasing their star-formation through a gradual exhaustion of gas supply or already dead and are experiencing a rejuvenation of star-formation through fuel injection. We use the Galaxy And Mass Assembly database and the Galaxy Zoo citizen science morphological estimates to compare the morphology of galaxies in the green valley against those in the red sequence and blue cloud. Our goal is to examine the structural differences …

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Probing Free Nucleons With (Anti)Neutrinos, Roberto Petti Nov 2022

Probing Free Nucleons With (Anti)Neutrinos, Roberto Petti

Faculty Publications

We discuss a method to study free protons and neutrons using ν(⊽)-hydrogen (H) Charged Current (CC) inelastic interactions, together with various precision tests of the isospin (charge) symmetry using ν and ⊽ CC interactions on both H and nuclear targets. Probing free nucleons with (anti)neutrinos provides information about their partonic structure, as well as a crucial input for the modeling of ν(⊽)-nucleus (A) interactions. Such measurements concurrently represent a valuable tool to address the main limitations of accelerator-based neutrino scattering experiments on nuclear targets, originating from the combined effect of the unknown (anti)neutrino energy and of the …

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Orbit Propagation And Determination Algorithms For Satellite Ground Stations, Shamma Esmaeel Jamali Nov 2022

Orbit Propagation And Determination Algorithms For Satellite Ground Stations, Shamma Esmaeel Jamali

Theses

The satellite orbital parameters are essential for satellite operations. With these parameters, it is possible to estimate the satellite position in the recent past and near future, which is essential to effectively plan satellite operations and associate satellite telemetry with geographical locations.
However, for small or medium satellite operators who do not possess the infrastructure required to track their satellites, the problem of determining the satellite orbit is problematic. To access the orbit for their satellites, these organizations have to rely on third parties such as Celestrak. These entities provide the service free of charge but do not provide orbital …

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A Method To Solve One-Dimensional Nonlinear Fractional Differential Equation Using B-Polynomials, Md. Habibur Rahman, Muhammad I. Bhatti, Nicholas Dimakis Nov 2022

A Method To Solve One-Dimensional Nonlinear Fractional Differential Equation Using B-Polynomials, Md. Habibur Rahman, Muhammad I. Bhatti, Nicholas Dimakis

Physics and Astronomy Faculty Publications and Presentations

In this article, the fractional Bhatti-Polynomial bases are applied to solve one-dimensional nonlinear fractional differential equations (NFDEs). We derive a semi-analytical solution from a matrix equation using an operational matrix which is constructed from the terms of the NFDE using Caputo’s fractional derivative of fractional B-polynomials (B-polys). The results obtained using the prescribed method agree well with the analytical and numerical solutions presented by other authors. The legitimacy of this method is demonstrated by using it to calculate the approximate solutions to four NFDEs. The estimated solutions to the differential equations have also been compared with other known numerical and …

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Which Countries Are Leading High-Impact Science In Astronomy?, Juan P. Madrid, Julie Steen Oct 2022

Which Countries Are Leading High-Impact Science In Astronomy?, Juan P. Madrid, Julie Steen

Physics and Astronomy Faculty Publications and Presentations

Recent news reports claim that China is overtaking the United States and all other countries in scientific productivity and scientific impact. A straightforward analysis of high-impact papers in astronomy reveals that this is not true in our field. In fact, the United States continues to host, by a large margin, the authors that lead high-impact papers. Moreover, this analysis shows that 90% of all high-impact papers in astronomy are led by authors based in North America and Europe. That is, only about 10% of countries in the world host astronomers that publish “astronomy’s greatest hits".

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The Spectro-Temporal Relationships Of Repeating Fast Radio Bursts, Mohammed Afif Chamma Oct 2022

The Spectro-Temporal Relationships Of Repeating Fast Radio Bursts, Mohammed Afif Chamma

Electronic Thesis and Dissertation Repository

Fast radio bursts (FRBs) are short and extremely energetic bursts of radiation detected from galaxies across the universe that occur thousands of times a day. Despite advances in instrumentation, it is difficult to explain the enormous implied energy reservoirs of FRBs, their emission mechanism and the existence of repeating and periodic sources. This thesis explores the spectro-temporal properties of repeating FRBs and details the discovery of several new relationships between them, providing valuable information on the nature of FRBs. By measuring the spectro-temporal properties of a sample of bursts from the repeating source FRB20121102A I show that the magnitude of …

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Deep Investigation Of Neutral Gas Origins (Dingo): Hi Stacking Experiments With Early Science Data, Jonghwan Rhee, Richard Dodson, Kristóf Rozgonyi, Sarah Brough, Benne Holwerda, Simon Driver, Attila Popping, Sambit Roychowdhury, Sabine Bellstedt, Michael J. I. Brown, Lister Staveley-Smith, Ivan Baldry, Angel Lopez-Sanchez, Martin Meyer, Elizabeth Mahony, Aaron Robotham, Andrew Hopkins, Karen Lee-Waddell Oct 2022

Deep Investigation Of Neutral Gas Origins (Dingo): Hi Stacking Experiments With Early Science Data, Jonghwan Rhee, Richard Dodson, Kristóf Rozgonyi, Sarah Brough, Benne Holwerda, Simon Driver, Attila Popping, Sambit Roychowdhury, Sabine Bellstedt, Michael J. I. Brown, Lister Staveley-Smith, Ivan Baldry, Angel Lopez-Sanchez, Martin Meyer, Elizabeth Mahony, Aaron Robotham, Andrew Hopkins, Karen Lee-Waddell

Faculty and Staff Scholarship

We present early science results from Deep Investigation of Neutral Gas Origins (DINGO), an H I survey using the Australian Square Kilometre Array Pathfinder (ASKAP). Using ASKAP subarrays available during its commissioning phase, DINGO early science data were taken over ∼60 deg2 of the Galaxy And Mass Assembly (GAMA) 23 h region with 35.5 h integration time. We make direct detections of six known and one new sources at z < 0.01. Using H I spectral stacking, we investigate the H I gas content of galaxies at 0.04 < z < 0.09 for different galaxy colours. The results show that galaxy morphology based on optical colour is strongly linked to H I gas properties. To examine environmental impacts on the H I gas content of galaxies, three subsamples are made based on the GAMA group catalogue. The average H I mass of group central galaxies is larger than those of satellite and isolated galaxies, but with a lower H I gas fraction. We derive a variety of H I scaling relations for physical properties of our sample, including stellar mass, stellar mass surface density, NUV − r colour, specific star formation rate, and halo mass. We find that the derived H I scaling relations are comparable to other published results, with consistent trends also observed to ∼0.5 dex lower limits in stellar mass and stellar surface density. The cosmic H I densities derived from our data are consistent with other published values at similar redshifts. DINGO early science highlights the power of H I spectral stacking techniques with ASKAP

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Probing The Extent Of Vertical Mixing In Brown Dwarf Atmospheres With Disequilibrium Chemistry, Sagnick Mukherjee, Jonathan J. Fortney, Natasha E. Batalha, Theodora Karalidi, Mark S. Marley, Channon Visscher, Brittany E. Miles, Andrew J. I. Skemer Oct 2022

Probing The Extent Of Vertical Mixing In Brown Dwarf Atmospheres With Disequilibrium Chemistry, Sagnick Mukherjee, Jonathan J. Fortney, Natasha E. Batalha, Theodora Karalidi, Mark S. Marley, Channon Visscher, Brittany E. Miles, Andrew J. I. Skemer

Faculty Work Comprehensive List

Evidence of disequilibrium chemistry due to vertical mixing in the atmospheres of many T- and Y-dwarfs has been inferred due to enhanced mixing ratios of CO and reduced NH3. Atmospheric models of planets and brown dwarfs typically parameterize this vertical mixing phenomenon with the vertical eddy diffusion coefficient, Kzz. While Kzz can perhaps be approximated in the convective regions in the atmosphere with mixing length theory, in radiative regions, the strength of vertical mixing is uncertain by many orders of magnitude. With a new grid of selfconsistent 1D model atmospheres from Teff of 400–1000 K, computed with a new radiative-convective …

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A Comparative L-Dwarf Sample Exploring The Interplay Between Atmospheric Assumptions And Data Properties, Eileen C. Gonzales, Ben Burningham, Jacqueline K. Faherty, Nikole K. Lewis, Channon Visscher, Mark Marley Oct 2022

A Comparative L-Dwarf Sample Exploring The Interplay Between Atmospheric Assumptions And Data Properties, Eileen C. Gonzales, Ben Burningham, Jacqueline K. Faherty, Nikole K. Lewis, Channon Visscher, Mark Marley

Faculty Work Comprehensive List

Comparisons of atmospheric retrievals can reveal powerful insights on the strengths and limitations of our data and modeling tools. In this paper, we examine a sample of five L dwarfs of similar effective temperature (Teff) or spectral type to compare their pressure–temperature (P-T) profiles. Additionally, we explore the impact of an object's metallicity and the signal-to-noise ratio (S/N) of the observations on the parameters we can retrieve. We present the first atmospheric retrievals: 2MASS J15261405+2043414, 2MASS J05395200−0059019, 2MASS J15394189−0520428, and GD 165B increasing the small but growing number of L dwarfs retrieved. When compared to the atmospheric retrievals …

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Detectability Of Wormholes Through Various Methods, Jonathan W. Keathley Oct 2022

Detectability Of Wormholes Through Various Methods, Jonathan W. Keathley

PANDION: The Osprey Journal of Research and Ideas

There are three methods that can possibly detect wormholes: Negative Temperature, Hawking/ Phantom Radiation, and Kα iron emission lines. This paper discusses whether or not any of these three methods are useful ways to detect wormholes with today’s technology and if so, which one is the best and which is the worst. As it turns out, all of these methods have their flaws and impracticalities. After looking through all the evidence and comparing it to what capabilities we have currently, there is clearly a best and worst method. The best method to detect possible wormhole candidates is through the detection …

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2022 Scas Annual Meeting Program And Bulletin Oct 2022

2022 Scas Annual Meeting Program And Bulletin

Journal of the South Carolina Academy of Science

No abstract provided.

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Table Of Contents Oct 2022

Table Of Contents

Journal of the South Carolina Academy of Science

No abstract provided.

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Separation Of Track- And Shower-Like Energy Deposits In Protodune-Sp Using A Convolutional Neural Network, A. Abed Abud, B. Abi, R, Acciarri, M. A. Acero, M. R. Adames, G. Adamov, M. Adamowski, D. Adams, M. Adinolfi, A. Aduszkiewicz, M. Andreotti, M. Andrews, F. Andrianala, S. Andringa, N. Anfimov, A. Ankowski, M. Antoniassi, M. Antonova, A. Antoshkin, S. Antusch, Roberto Petti, Et. Al. Oct 2022

Separation Of Track- And Shower-Like Energy Deposits In Protodune-Sp Using A Convolutional Neural Network, A. Abed Abud, B. Abi, R, Acciarri, M. A. Acero, M. R. Adames, G. Adamov, M. Adamowski, D. Adams, M. Adinolfi, A. Aduszkiewicz, M. Andreotti, M. Andrews, F. Andrianala, S. Andringa, N. Anfimov, A. Ankowski, M. Antoniassi, M. Antonova, A. Antoshkin, S. Antusch, Roberto Petti, Et. Al.

Faculty Publications

Liquid argon time projection chamber detector technology provides high spatial and calorimetric resolutions on the charged particles traversing liquid argon. As a result, the technology has been used in a number of recent neutrino experiments, and is the technology of choice for the Deep Underground Neutrino Experiment (DUNE). In order to perform high precision measurements of neutrinos in the detector, final state particles need to be effectively identified, and their energy accurately reconstructed. This article proposes an algorithm based on a convolutional neural network to perform the classification of energy deposits and reconstructed particles as track-like or arising from electromagetic …

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Tau Neutrinos In The Next Decade: From Gev To Eev, Roshan Mammen Abraham, Jamie Alvarez-Muñiz, Carlos A. Argüelles, Akitaka Ariga, Tomoko Ariga, Adam Aurisano, Dario Autiero, Mary Bishai, Nilay Bostan, Mauricio Bustamante, Austin Cummings, Valentin Decoene, André De Gouvêa, Giovanni De Lellis, Albert De Roeck, Peter B. Denton, Antonia Di Crescenzo, Milind V. Diwan, Yasaman Farzan, Anatoli Fedynitch, Jonathan L. Feng, Laura J. Fields, Alfonso Garcia, Maria Vittoria Garzelli, Julia Gehrlein, Christian Glaser, Katarzyna Grzelak, Steffen Hallmann, Jeremy Hewes, D Indumathi, Ahmed Ismail, Sudip Jana, Yu Seon Jeong, Kevin J. Kelly, Spencer R. Klein, Felix Kling, Thomas Kosc, Umut Kose, D Jason Koskinen, John Krizmanic, Jeff Lazar, Yichen Li, Ivan Martinez-Soler, Irina Mocioiu, Jiwoo Nam, Valentin Niess, Nepomuk Otte, Sameer Patel, Roberto Petti, Et. Al. Oct 2022

Tau Neutrinos In The Next Decade: From Gev To Eev, Roshan Mammen Abraham, Jamie Alvarez-Muñiz, Carlos A. Argüelles, Akitaka Ariga, Tomoko Ariga, Adam Aurisano, Dario Autiero, Mary Bishai, Nilay Bostan, Mauricio Bustamante, Austin Cummings, Valentin Decoene, André De Gouvêa, Giovanni De Lellis, Albert De Roeck, Peter B. Denton, Antonia Di Crescenzo, Milind V. Diwan, Yasaman Farzan, Anatoli Fedynitch, Jonathan L. Feng, Laura J. Fields, Alfonso Garcia, Maria Vittoria Garzelli, Julia Gehrlein, Christian Glaser, Katarzyna Grzelak, Steffen Hallmann, Jeremy Hewes, D Indumathi, Ahmed Ismail, Sudip Jana, Yu Seon Jeong, Kevin J. Kelly, Spencer R. Klein, Felix Kling, Thomas Kosc, Umut Kose, D Jason Koskinen, John Krizmanic, Jeff Lazar, Yichen Li, Ivan Martinez-Soler, Irina Mocioiu, Jiwoo Nam, Valentin Niess, Nepomuk Otte, Sameer Patel, Roberto Petti, Et. Al.

Faculty Publications

Tau neutrinos are the least studied particle in the standard model. This whitepaper discusses the current and expected upcoming status of tau neutrino physics with attention to the broad experimental and theoretical landscape spanning long-baseline, beam-dump, collider, and astrophysical experiments. This whitepaper was prepared as a part of the NuTau2021 Workshop.

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Extended Duration Studies Of Energetic Particles In The Stratosphere, Ian Kuhl, Ashna Coondiah, Howard Brooks Oct 2022

Extended Duration Studies Of Energetic Particles In The Stratosphere, Ian Kuhl, Ashna Coondiah, Howard Brooks

Annual Student Research Poster Session

The Balloon Assisted Stratospheric Experiments (BASE) program aims to measure atmospheric muon concentration at the Pfotzer Maximum with Geiger Counters carried by weather balloons. The most intense radiation is found at the Pfotzer Maximum 18 - 22 km (11 - 13 mi) above ground level. During this summer, seven flights were conducted to attain maximum time in the Pfotzer Maximum using different strategies like underfilling and multiple balloon systems.

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