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The Loneliest Galaxies In The Universe: A Gama And Galaxy Zoo Study On Void Galaxy Morphology., Lori E. Porter 2023 University of Louisville

The Loneliest Galaxies In The Universe: A Gama And Galaxy Zoo Study On Void Galaxy Morphology., Lori E. Porter

College of Arts & Sciences Senior Honors Theses

The large-scale structure (LSS) 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 voids are void galaxies and expected to be some of the most isolated objects in the Universe. However, their standard morphology remains poorly studied. This study, using the Galaxy and Mass Assembly (GAMA) data and Galaxy Zoo survey, aims to remedy this. For completeness purposes, we use void galaxies identified by Alpaslan et al. (2014) with stellar masses (M*) of ...


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 2022 The University of Texas Rio Grande Valley

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 ...


Collation Model For Ljs 64: [Illustrations To Georg Von Peurbach's Novae Theoricae Planetarum]., Dot Porter 2022 University of Pennsylvania

Collation Model For Ljs 64: [Illustrations To Georg Von Peurbach's Novae Theoricae Planetarum]., Dot Porter

Collation Models

Diagrams, many with moving parts, designed to accompany the work Theoricae novae planetarum by 15th-century Austrian astronomer Georg von Peurbach, who taught at the universities in Padua and Ferrara. The diagrams demonstrate increasingly complex planetary motion. An early 17th-century inscription on the first flyleaf refers to an edition of Peurbach published in Venice in 1616.


Collation Model For Ms. Codex 761: [Cosmographies]., Dot Porter 2022 University of Pennsylvania

Collation Model For Ms. Codex 761: [Cosmographies]., Dot Porter

Collation Models

Four ancient Greek cosmographies in Latin translation: Plato's Timaeus translated and with a commentary by Calcidius, Aristotle's De mundo translated by Ioannes Argyropoulos, Philo's De incorruptione mundi probably translated by Lilius Tifernas, and Cleomedes's De mundo translated by Carolus Valgulius.


Physics 516: Electromagnetic Phenomena (Spring 2023), Philip C. Nelson 2022 University of Pennsylvania

Physics 516: Electromagnetic Phenomena (Spring 2023), Philip C. Nelson

Department of Physics Papers

These course notes are made publicly available in the hope that they will be useful. All reports of errata will be gratefully received. I will also be glad to hear from anyone who reads them, whether or not you find errors: pcn@upenn.edu.


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 2022 Andrews University

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 ...


Collation Model For Ljs 361: [Astronomical And Astrological Tables]., Dot Porter 2022 University of Pennsylvania

Collation Model For Ljs 361: [Astronomical And Astrological Tables]., Dot Porter

Collation Models

Opening and closing sections of astronomical and astrological tables on either side of a remnant of commentaries on gospel and epistle readings. The opening section (f. 2r-9r) includes tables for calculating the day of the week for any day from 1204 to 1512; the Sunday letter from 1204 to 1736; the golden letter from 1215 to 1728; movable feasts; time variation according to latitude and longitude; the conjunction of the sun and moon from January to September from 1327 to 1367; and the hours of day and night in any day of the year, as well as lists of human ...


Iterative Time-Domain Method For Resolving Multiple Gravitational Wave Sources In Pulsar Timing Array Data, Yi Qian Qian, Soumya D. Mohanty, Yan Wang 2022 The University of Texas Rio Grande Valley

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 ...


The Spectro-Temporal Relationships Of Repeating Fast Radio Bursts, Mohammed Afif Chamma 2022 The University of Western Ontario

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 ...


How Do Galaxies Form Their Stars Over Cosmic Time?, Jed H. McKinney 2022 University of Massachusetts Amherst

How Do Galaxies Form Their Stars Over Cosmic Time?, Jed H. Mckinney

Doctoral Dissertations

Galaxies in the past were forming more stars than those today, but the driving force behind this increase in activity remains uncertain. In this thesis I explore the origin of high star-formation rates today and in the past by studying the properties of gas and dust in the cold interstellar medium (ISM) of dusty galaxies over cosmic time. Critically, we do not yet understand how these galaxies could form so many stars. This work began with my discovery of unusual infrared (IR) emission line ratios in the class of dusty galaxies where most of the Universe’s stars were formed ...


Hyperspectral Unmixing: A Theoretical Aspect And Applications To Crism Data Processing, Yuki Itoh 2022 University of Massachusetts Amherst

Hyperspectral Unmixing: A Theoretical Aspect And Applications To Crism Data Processing, Yuki Itoh

Doctoral Dissertations

Hyperspectral imaging has been deployed in earth and planetary remote sensing, and has contributed the development of new methods for monitoring the earth environment and new discoveries in planetary science. It has given scientists and engineers a new way to observe the surface of earth and planetary bodies by measuring the spectroscopic spectrum at a pixel scale.

Hyperspectal images require complex processing before practical use. One of the important goals of hyperspectral imaging is to obtain the images of reflectance spectrum. A raw image obtained by hyperspectral remote sensing usually undergoes conversion to a physical quantity representing the intensity of ...


Detectability Of Wormholes Through Various Methods, Jonathan W. Keathley 2022 University of North Florida

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 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 ...


2022 Scas Annual Meeting Program And Bulletin, 2022 University of South Carolina

2022 Scas Annual Meeting Program And Bulletin

Journal of the South Carolina Academy of Science

No abstract provided.


Table Of Contents, 2022 University of South Carolina

Table Of Contents

Journal of the South Carolina Academy of Science

No abstract provided.


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

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.


Galaxy And Mass Assembly (Gama): Probing Galaxy-Group Correlations In Redshift Space With The Halo Streaming Model, Qianjun Hang, John A. Peacock, Shadab Alam, Yan-Chuan Cai, Katarina Kraljic, Marcel van Daalen, M Bilicki, Benne Holwerda, J Loveday 2022 University of Louisville

Galaxy And Mass Assembly (Gama): Probing Galaxy-Group Correlations In Redshift Space With The Halo Streaming Model, Qianjun Hang, John A. Peacock, Shadab Alam, Yan-Chuan Cai, Katarina Kraljic, Marcel Van Daalen, M Bilicki, Benne Holwerda, J Loveday

Faculty Scholarship

We have studied the galaxy-group cross-correlations in redshift space for the Galaxy And Mass Assembly (GAMA) Survey. We use a set of mock GAMA galaxy and group catalogues to develop and test a novel ‘halo streaming’ model for redshift-space distortions. This treats 2-halo correlations via the streaming model, plus an empirical 1-halo term derived from the mocks, allowing accurate modelling into the non-linear regime. In order to probe the robustness of the growth rate inferred from redshift-space distortions, we divide galaxies by colour, and divide groups according to their total stellar mass, calibrated to total mass via gravitational lensing. We ...


Dynamics Of Atmospheric Gravity Wave Breaking In The Mesopause Region, Fan Yang 2022 Embry-Riddle Aeronautical University

Dynamics Of Atmospheric Gravity Wave Breaking In The Mesopause Region, Fan Yang

Doctoral Dissertations and Master's Theses

GWs significantly impact the Mesosphere and Lower Thermosphere (MLT), and as a consequence of GW breaking, atmospheric turbulence plays an essential role in the mixing and transport of momentum, mass, and chemical materials in MLT. The main focus of this research for the fulfillment of the proposed Ph.D. dissertation is to improve the understanding of the dynamic process of wave breaking and their effects in the mesopause region above Andes Lidar Observatory (30.2◦ S, 70.7◦ W). A few scientific topics related to GW break- ing are addressed. What are the probabilities of the atmosphere becoming convectively or ...


Losing The Dark: How Light Pollution Impacts Humans And The Environment, And What We Can Do To Win Back The Night, Marc Gagné 2022 West Chester University of Pennsylvania

Losing The Dark: How Light Pollution Impacts Humans And The Environment, And What We Can Do To Win Back The Night, Marc Gagné

Sustainability Research & Practice Seminar Presentations

Professor Marc Gagne, Earth and Space Sciences - Losing the Dark: How light pollution impacts humans and the environment, and what we can do to win back the night


Search For Gravitational Waves From Scorpius X-1 With A Hidden Markov Model In O3 Ligo Data, R. Abbott, H. Abe, F. Acernese, K. Ackley, N. Adhikari, M. G. Benjamin, Teviet Creighton, Mario C. Diaz, Francisco Llamas, Soma Mukherjee, Gaukhar Nurbek, Volker Quetschke, Wenhui Wang 2022 The University of Texas Rio Grande Valley

Search For Gravitational Waves From Scorpius X-1 With A Hidden Markov Model In O3 Ligo Data, R. Abbott, H. Abe, F. Acernese, K. Ackley, N. Adhikari, 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

Results are presented for a semicoherent search for continuous gravitational waves from the low-mass x-ray binary Scorpius X-1, using a hidden Markov model (HMM) to allow for spin wandering. This search improves on previous HMM-based searches of Laser Interferometer Gravitational-Wave Observatory data by including the orbital period in the search template grid, and by analyzing data from the latest (third) observing run. In the frequency range searched, from 60 to 500 Hz, we find no evidence of gravitational radiation. This is the most sensitive search for Scorpius X-1 using a HMM to date. For the most sensitive subband, starting at ...


Kinetic Modeling Of Ionospheric Outflows Observed By The Visions-1 Sounding Rocket, Robert M. Albarran II 2022 Embry-Riddle Aeronautical University

Kinetic Modeling Of Ionospheric Outflows Observed By The Visions-1 Sounding Rocket, Robert M. Albarran Ii

Doctoral Dissertations and Master's Theses

Plasma escape from the high-latitude ionosphere (ion outflow) serves as a significant source of heavy plasma to magnetospheric plasma sheet and ring current regions. Outflows alter mass density and reconnection rates, hence global responses of the magnetosphere. The VISIONS-1 (VISualizing Ion Outflow via Neutral atom imaging during a Substorm) sounding rocket was launched on Feb. 7, 2013 at 8:21 UTC from Poker Flat, Alaska, into an auroral substorm with the objective of identifying the drivers and dynamics of nightside ion outflow at altitudes where it is initiated, below 1000 km. Energetic ion data from the VISIONS-1 polar cap boundary ...


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