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Full-Text Articles in Physical Sciences and Mathematics

Dr. Jennifer Hoffman, Anit Tyagi Jan 2022

Dr. Jennifer Hoffman, Anit Tyagi

DU Undergraduate Research Journal Archive

An interview with Dr. Jennifer Hoffman.


Design And Modal Analysis Of An Ultra-Wideband Receiver For Green Bank Observatory, Alyssa Bulatek May 2020

Design And Modal Analysis Of An Ultra-Wideband Receiver For Green Bank Observatory, Alyssa Bulatek

Macalester Journal of Physics and Astronomy

The next generation of radio receivers for astronomy will be marked by tenfold improvements in sensitivity. These sensitive receivers will be useful for the detection of broadband fast radio bursts and other transients as well as the efficient discovery of radio recombination lines among many other scientific pursuits. One contribution to these improvements is an increase to decade receiver bandwidths. The Green Bank Observatory (GBO) is currently in the process of fabricating a new ultra-wideband (UWB; 0.7 to 4.2 GHz) receiver for the Green Bank Telescope (GBT). The UWB receiver will be used by the North American Nanohertz Observatory for …


Automated Spectroscopic Detection And Mapping Using Alma And Machine Learningtechniques, Steven Cocke, Andrew Wilkins, Josephine Mcdaniel, John Santerre, Conor Nixon Apr 2020

Automated Spectroscopic Detection And Mapping Using Alma And Machine Learningtechniques, Steven Cocke, Andrew Wilkins, Josephine Mcdaniel, John Santerre, Conor Nixon

SMU Data Science Review

In this paper we present a methodology for automating theclassification of spectrally resolved observations of multiple emissionlines with the Atacama Large Millimeter/submillimeter Array (ALMA).Molecules in planetary atmospheres emit or absorb different wavelengthsof light thereby providing a unique signature for each species. ALMAdata were taken from interferometric observations of Titan made be-tween UT 2012 July 03 23:22:14 and 2012 July 04 01:06:18 as part ofALMA project 2011.0.00319.S. We first employed a greedy set cover algorithm to identify the most probable molecules that would reproducethe set of frequencies with respective flux greater than 3σaway from themean. We then selected a subset of …


Perfect Circles: A Study Of The Scattering Regions Of Wolf Rayet Binary Stars, Stella Yoos, Jennifer Hoffman, Andrew Fullard Apr 2020

Perfect Circles: A Study Of The Scattering Regions Of Wolf Rayet Binary Stars, Stella Yoos, Jennifer Hoffman, Andrew Fullard

DU Undergraduate Research Journal Archive

Although we have been able to develop an understanding of many aspects of stellar evolution and formation, a few key gaps remain. One is the fate of massive binary star systems composed of Wolf-Rayet (WR) and O-type stars. In these WR + O binaries, the stellar winds surrounding these stars collide, creating a complex interaction region in which light from the stars scatters and becomes polarized. To study these scattering regions, I employ a technique that allows me to map the polarization of the light emitted from these stars and track its variation over the binary orbit. I found that …


Preparing A Database Of Extremely High Velocity Outflows In Quasars, Griffin Kowash, Carla P. Quintero, Sean S. Haas, Paola Rodriguez Hidalgo Sep 2019

Preparing A Database Of Extremely High Velocity Outflows In Quasars, Griffin Kowash, Carla P. Quintero, Sean S. Haas, Paola Rodriguez Hidalgo

IdeaFest: Interdisciplinary Journal of Creative Works and Research from Cal Poly Humboldt

No abstract provided.


Magic, Matrimony, And The Moon: Medieval Lunar Symbolism In J.R.R. Tolkien’S “The Lay Of Aotrou And Itroun” And “The Fall Of Arthur”, Kristine Larsen Nov 2018

Magic, Matrimony, And The Moon: Medieval Lunar Symbolism In J.R.R. Tolkien’S “The Lay Of Aotrou And Itroun” And “The Fall Of Arthur”, Kristine Larsen

Journal of Tolkien Research

This paper (originally delivered at the 2017 International Medieval Congress at the University of Leeds, UK) explores common lunar symbolism in "The Lay of Aotrou and Itroun" and "The Fall of Arthur."


Totality In Carbondale, Grant Haynes Aug 2018

Totality In Carbondale, Grant Haynes

The Hilltop Review

August 21 was one of the high points of 2017. That day a total solar eclipse tracked over much of the continental U.S. An early morning train ride brought me to Carbondale Illinois, the location of the eclipses longest duration. As totality neared clouds obscured this amazing celestial wonder, but they soon parted, and I was able to get a few spectacular photos of the eclipse, this one with the clouds that almost ruined it, is my favorite.


Searching For A Connection Between Radio Emission And Uv/Optical Absorption In Quasars, Sean S. Haas, Carla P. Quintero, Paola Rodriguez Hidalgo Jun 2018

Searching For A Connection Between Radio Emission And Uv/Optical Absorption In Quasars, Sean S. Haas, Carla P. Quintero, Paola Rodriguez Hidalgo

IdeaFest: Interdisciplinary Journal of Creative Works and Research from Cal Poly Humboldt

No abstract provided.


Cataclysmic Variable Stars In The Sloan Digital Sky Survey, Sinead Humphrey, Samantha Smiley, Andres Munoz, Brian Saboriendo May 2018

Cataclysmic Variable Stars In The Sloan Digital Sky Survey, Sinead Humphrey, Samantha Smiley, Andres Munoz, Brian Saboriendo

DePaul Discoveries

The purpose of this study is to identify Cataclysmic Variables (CVs) using spectroscopic and photometric data. CVs are useful for studying plasma physics in extreme conditions such as the high temperature and strong magnetic fields seen in CV accretion disks. They are also critical for understanding the evolution of binary stars, both in the field and in globular clusters. This project used photometric and spectroscopic data from the Sloan Digital Sky Survey (SDSS) to identify and classify CVs. 6,000 objects were selected based on multi-color criteria and analyzed using spectral data. Approximately 1% of these objects in the sample were …


An Introduction To The Quasi-Optical Design Of The Hifi Instrument For The Herschel Space Observatory, Gareth S. Curran, J. Anthony Murphy May 2017

An Introduction To The Quasi-Optical Design Of The Hifi Instrument For The Herschel Space Observatory, Gareth S. Curran, J. Anthony Murphy

The ITB Journal

This paper is concerned with the quasi-optical design and analysis of the Heterodyne Instrument for the Far Infrared (HIFI) on board the European Space Agency’s Herschel Space Observatory, which is due for launch in 2007. The paper begins with an introduction to astronomy at submillimetre wavelengths followed by the science that will be carried out by HIFI. The optical layout of HIFI is presented and the quasi-optical techniques used in the analysis of band 5 of the instrument are discussed, in particular, issues associated with the design and performance of the integrated lens antenna for this band. A power coupling …


Exoplanet Research: Differential Photometry For Kepler 6b, Garrett T. Benson, Charlotte Alexandra Olsen Oct 2016

Exoplanet Research: Differential Photometry For Kepler 6b, Garrett T. Benson, Charlotte Alexandra Olsen

IdeaFest: Interdisciplinary Journal of Creative Works and Research from Cal Poly Humboldt

No abstract provided.


Medieval Cosmology And Middle-Earth: A Lewisian Walk Under Tolkienian Skies, Kristine Larsen May 2016

Medieval Cosmology And Middle-Earth: A Lewisian Walk Under Tolkienian Skies, Kristine Larsen

Journal of Tolkien Research

A nearly identical version of this paper was delivered at the 30th Annual International Conference on Medievalism in Pittsburgh, Pennsylvania on October 2, 2015, as part of a session on the Inklings and Medievalism.


Detection Of Baryonic Acoustic Oscillations In The Matter Power Spectrum, Spencer Everett, Ian Johnson, Jon Murphy, Mary Tarpley May 2015

Detection Of Baryonic Acoustic Oscillations In The Matter Power Spectrum, Spencer Everett, Ian Johnson, Jon Murphy, Mary Tarpley

DePaul Discoveries

Using the spectra of 22,923 high-redshift quasars from the Baryon Oscillation Spectrosocpic Survey (BOSS) subset of the Sloan Digital Sky Survey (SDSS), the authors detect evidence of the primordial baryonic acoustic oscillations (BAOs) in the matter power spectrum. The detection further endorses the currently accepted Lambda-CDM model of cosmology based upon the existence of dark energy (Lambda) and cold dark matter (CDM). Additionally, the use of the continuous wavelet transform to calculate the power spectrum has many advantages over traditional Fourier methods and independently corroborates previous detections.


The Ptolemaic System: A Detailed Synopsis, John Cramer Dr. Apr 2015

The Ptolemaic System: A Detailed Synopsis, John Cramer Dr.

Oglethorpe Journal of Undergraduate Research

The Ptolemaic System, constructed by Claudius Ptolemeus (the Latin form of his name), was the most influential of all Earth centered cosmological systems. His ingenious and creative work is primarily recorded in his book The Mathematical Systematic Treatise which the Arabs characterized as “the greatest” and, in so doing, gave the book its most used name, Almagest.


On The Detection Of Exoplanets Via Radial Velocity Doppler Spectroscopy, Joseph P. Glaser Jan 2015

On The Detection Of Exoplanets Via Radial Velocity Doppler Spectroscopy, Joseph P. Glaser

The Downtown Review

Since the discovery of the first exoplanet occurred in the late 1980s, physicists and astronomers have confirmed the existence of over 1783 planets orbiting other stars. Over the years, several methods have been developed for detecting these celestial systems, but none has thus far been more successful than the use of Radial Velocity Doppler Spectroscopy. As such, this paper attempts to break down the barriers placed before new entries into the field by detailing the theoretical premise and experimental process of this most successful technique. The content enclosed is geared for the senior undergraduate student with some knowledge of vector-based …


Astronomy / Galactic Structure - Rensselaer Polytechnic Institute, Kathryn M. Dunn Apr 2013

Astronomy / Galactic Structure - Rensselaer Polytechnic Institute, Kathryn M. Dunn

Data Curation Profiles Directory

The researcher participates in large-scale astronomical survey projects, which are collaborative efforts of many institutions and individuals. Management of the raw and processed/calibrated data is handled by those projects, but data for specific research questions is handled by the researcher. The researcher would like to have a better way to share the data behind the figures in their published papers with other researchers. The effort involved in retrieving and documenting the data so it’s usable by others is a barrier to sharing the data. It would be easier to share data from publications if it could be deposited to a …


The Study Of Recent Comets, William W. Payne Dec 1882

The Study Of Recent Comets, William W. Payne

Journal of the Minnesota Academy of Science

No abstract provided.


The Fixed Stars, John F. Downey Dec 1880

The Fixed Stars, John F. Downey

Journal of the Minnesota Academy of Science

The object of this paper is to give, in a popular form, a brief review of what is known about the fixed stars. Although they have always been objects of interest, have guided the mariner over trackless seas, arid have inspired many sublime and noble thoughts, yet, until a comparatively recent date, only three things were known about them; viz., that they retain (approximately) their ·relative positions, that they are self luminous, and that they are very far away.


The Spectroscope In Astronomy, W. W. Payne Dec 1880

The Spectroscope In Astronomy, W. W. Payne

Journal of the Minnesota Academy of Science

No abstract provided.


Astronomy—Scientific And Unscientific, G. W. Tinsley Dec 1873

Astronomy—Scientific And Unscientific, G. W. Tinsley

Journal of the Minnesota Academy of Science

No abstract provided.