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Real-Time Rfi Mitigation In Radio Astronomy, Emily Ramey, Nick Joslyn, Richard Prestage, Michael Lam, Luke Hawkins, Tim Blattner, Mark Whitehead 2019 Washington University in St. Louis

Real-Time Rfi Mitigation In Radio Astronomy, Emily Ramey, Nick Joslyn, Richard Prestage, Michael Lam, Luke Hawkins, Tim Blattner, Mark Whitehead

Senior Honors Papers / Undergraduate Theses

As the use of wireless technology has increased around the world, Radio Frequency Interference (RFI) has become more and more of a problem for radio astronomers. Preventative measures exist to limit the presence of RFI, and programs exist to remove it from saved data, but the use of algorithms to detect and remove RFI as an observation is occurring is much less common. Such a method would be incredibly useful for observations in which the data must undergo several rounds of processing before being saved, as in pulsar timing studies. Strategies for real-time mitigation have been discussed and tested with ...


Automation And Enhancements To The Erau Oscom System Space Situational Awareness, Sergei Bilardi, Patrick Rupp, Yevgeniy Lischuk, Joseph Stroup 2018 Embry-Riddle Aeronautical University

Automation And Enhancements To The Erau Oscom System Space Situational Awareness, Sergei Bilardi, Patrick Rupp, Yevgeniy Lischuk, Joseph Stroup

Beyond: Undergraduate Research Journal

OSCOM, Optical tracking and Spectral characterization of CubeSats for Operational Missions, is a system developed at Embry-Riddle Aeronautical University to produce time-resolved photometry of small satellites using commercial-off-the-shelf hardware. OSCOM has been able to observe resident space objects (RSOs) as small as CubeSats using a Celestron 11” RASA and a CMOS machine vision camera from Allied Vision. By obtaining photometric measurements of satellites, a light curve can be constructed and used to help determine satellite characteristics such as spin rate, satellite state, and even satellite attitude. To enhance the OSCOM system’s ability to observe small satellites, there is ongoing ...


Book Review: Spectral Atlas For Amateur Astronomers: A Guide To The Spectra Of Astronomical Objects And Terrestrial Light Sources, T. D. Oswalt 2018 Embry-Riddle Aeronautical University

Book Review: Spectral Atlas For Amateur Astronomers: A Guide To The Spectra Of Astronomical Objects And Terrestrial Light Sources, T. D. Oswalt

Publications

This document is Dr. Oswalt’s review of Spectral Atlas for Amateur Astronomers: A Guide to the Spectra of Astronomical Objects and Terrestrial Light Sources by Richard Walker. Cambridge 2017, 277 p bibl index, 9781107165908 $89.99, 9781316731048 $72.00


Kelvin-Helmholtz Instability: Lessons Learned And Ways Forward, A. Masson, K. Nykyri 2018 European Space Agency

Kelvin-Helmholtz Instability: Lessons Learned And Ways Forward, A. Masson, K. Nykyri

Publications

The Kelvin–Helmholtz instability (KHI) is a ubiquitous phenomenon across the Universe, observed from 500 m deep in the oceans on Earth to the Orion molecular cloud. Over the past two decades, several space missions have enabled a leap forward in our understanding of this phenomenon at the Earth’s magnetopause. Key results obtained by these missions are first presented, with a special emphasis on Cluster and THEMIS. In particular, as an ideal instability, the KHI was not expected to produce mass transport. Simulations, later confirmed by spacecraft observations, indicate that plasma transport in Kelvin–Helmholtz (KH) vortices can arise ...


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

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 ...


A Spatially-Resolved X-Ray Spectroscopic Analysis Of The Luminous Northeastern Rim Of The Galactic Supernova Remnant W28 (G6.4-0.1), Sarah Norris, Thomas Pannuti 2018 Department of Earth and Space Sciences, College of Science

A Spatially-Resolved X-Ray Spectroscopic Analysis Of The Luminous Northeastern Rim Of The Galactic Supernova Remnant W28 (G6.4-0.1), Sarah Norris, Thomas Pannuti

Celebration of Student Scholarship Posters Archive

No abstract provided.


The Automation Of Analysis Procedures For The Citizen Cate Experiment Eclipse Data, Logan Jensen, Michael Pierce 2018 University of Wyoming

The Automation Of Analysis Procedures For The Citizen Cate Experiment Eclipse Data, Logan Jensen, Michael Pierce

Honors Theses AY 17/18

The Citizen Continental-America Telescopic Eclipse Experiment deployed 68 volunteer-operated telescope and camera systems across the United States to collect continuous data of the August 2017 solar eclipse. For any one location the eclipse lasted 2.5 minutes, but in total the nationwide CATE network collected data on the full 93 minutes of eclipse across America. The wealth of data collected contains more than 110,000 calibration and eclipse images and takes up 1.5 terabytes of memory. To become scientifically applicable, all these images needed to be corrected for systematic errors caused by the equipment and for human error. The ...


Education, Support, And Results For Wyoming Participants In The Citizen Cate (Continental-America Telescopic Eclipse) Experiment, Gabriel Miller 2018 University of Wyoming

Education, Support, And Results For Wyoming Participants In The Citizen Cate (Continental-America Telescopic Eclipse) Experiment, Gabriel Miller

Honors Theses AY 17/18

Throughout the spring and summer of 2017, the Citizen CATE (Continental- America Telescopic Eclipse) Experiment was active in Wyoming and across the contiguous United States, with the goal of achieving an unbroken line of citizen- operated telescopes and cameras along the path of totality for the August eclipse. Eleven sites were active in Wyoming, composed of teachers, students, amateur and professional astronomers, and interested members of the community. In two large educational sessions, as well as several localized practice events, these groups were trained to use the telescopes and cameras provided for them. Working closely with the National Solar Observatory ...


Against Common Sense, Channon Visscher 2018 Dordt College

Against Common Sense, Channon Visscher

Faculty Work Comprehensive List

"Scientific inquiry... allows for the exploration of phenomena that would otherwise remain beyond human intuition."

Posting about ­­­­­­­­beauty and truth in creation from In All Things - an online journal for critical reflection on faith, culture, art, and every ordinary-yet-graced square inch of God’s creation.

https://inallthings.org/against-common-sense/


Cosmological Distance Measurements With Rotse Supernovae Iip And Observational Systematics On Desi Emission Line Galaxy Clustering, Govinda Dhungana 2018 Southern Methodist University

Cosmological Distance Measurements With Rotse Supernovae Iip And Observational Systematics On Desi Emission Line Galaxy Clustering, Govinda Dhungana

Physics Theses and Dissertations

Both Supernovae (SNe) and Baryon Acoustic Oscillations (BAO) surveys emerged as complementary probes of the expansion history of the universe in the last few decades. SNe Ia cosmology has reached the systematic limits in the optical surveys. The most frequently occuring SNe Type IIP are emerging as equally rich distance probes for the next generation larger surveys. In this thesis, I highlight the astrophysical observables of these events in the context of ROTSE III SN survey and using the ROTSE SNe IIP sample, I present calibration in the framework of expanding photosphere method (EPM) to use them as cosmological distance ...


An Investigation Into The Suitability Of Sulfate-Reducing Bacteria As Models For Martian Forward Contamination, Maxwell M. W. Silver 2018 University of Arkansas, Fayetteville

An Investigation Into The Suitability Of Sulfate-Reducing Bacteria As Models For Martian Forward Contamination, Maxwell M. W. Silver

Theses and Dissertations

The NASA Planetary Protection policy requires interplanetary space missions do not compromise the target body for a current or future scientific investigation and do not pose an unacceptable risk to Earth, including biologic materials. Robotic missions to Mars pose a risk to planetary protection in the forms of forward and reverse contamination. To reduce these risks, a firm understanding of microbial response to Mars conditions is required. Sulfate-reducing bacteria are prime candidates for potential forward contamination on Mars. Understanding the potential for forward-contamination of sulfate-reducers on Mars calls for the characterization of sulfate-reducers under Mars atmosphere, temperature, and sulfate-brines. This ...


The Stellar Populations Of Two Ultra-Diffuse Galaxies From Optical And Near-Infrared Photometry, Viraj Pandya, Aaron J. Romanowsky, Seppo Laine, Jean Brodie, Benjamin Johnson, William Glaccum, Alexa Villaume, Jean-Charles Cuillandre, Stephen Gwyn, Jessica Krick, Ronald Lasker, Ignacio Martín-Navarro, David Martinez-Delgado, Pieter van Dokkum 2018 University of California, Santa Cruz

The Stellar Populations Of Two Ultra-Diffuse Galaxies From Optical And Near-Infrared Photometry, Viraj Pandya, Aaron J. Romanowsky, Seppo Laine, Jean Brodie, Benjamin Johnson, William Glaccum, Alexa Villaume, Jean-Charles Cuillandre, Stephen Gwyn, Jessica Krick, Ronald Lasker, Ignacio Martín-Navarro, David Martinez-Delgado, Pieter Van Dokkum

Faculty Publications

We present observational constraints on the stellar populations of two ultra-diffuse galaxies (UDGs) using optical through near-infrared (NIR) spectral energy distribution (SED) fitting. Our analysis is enabled by new Spitzer-IRAC 3.6 and 4.5 μm imaging, archival optical imaging, and the prospectorfully Bayesian SED fitting framework. Our sample contains one field UDG (DGSAT I), one Virgo cluster UDG (VCC 1287), and one Virgo cluster dwarf elliptical for comparison (VCC 1122). We find that the optical–NIR colors of the three galaxies are significantly different from each other. We infer that VCC 1287 has an old (7.7 ...


The Stellar Populations Of Two Ultra-Diffuse Galaxies From Optical And Near-Infrared Photometry, Viraj Pandya, Aaron J. Romanowsky, Seppo Laine, Jean P. Brodie, Benjamin D. Johnson, William Glaccum, Alexa Villaume, Jean-Charles Cuillandre, Stephen Gwyn, Jessica Krick, Ronald Lasker, Ignacio Martín-Navarro, David Martinez-Delgado, Pieter G. van Dokkum 2018 University of California, Santa Cruz

The Stellar Populations Of Two Ultra-Diffuse Galaxies From Optical And Near-Infrared Photometry, Viraj Pandya, Aaron J. Romanowsky, Seppo Laine, Jean P. Brodie, Benjamin D. Johnson, William Glaccum, Alexa Villaume, Jean-Charles Cuillandre, Stephen Gwyn, Jessica Krick, Ronald Lasker, Ignacio Martín-Navarro, David Martinez-Delgado, Pieter G. Van Dokkum

Aaron J. Romanowsky

We present observational constraints on the stellar populations of two ultra-diffuse galaxies (UDGs) using optical through near-infrared (NIR) spectral energy distribution (SED) fitting. Our analysis is enabled by new Spitzer-IRAC 3.6 and 4.5 μm imaging, archival optical imaging, and the prospectorfully Bayesian SED fitting framework. Our sample contains one field UDG (DGSAT I), one Virgo cluster UDG (VCC 1287), and one Virgo cluster dwarf elliptical for comparison (VCC 1122). We find that the optical–NIR colors of the three galaxies are significantly different from each other. We infer that VCC 1287 has an old (7 ...


Upper Limits On The Presence Of Central Massive Black Holes In Two Ultra-Compact Dwarf Galaxies In Centaurus A, Karina Voggel, Anil Seth, Nadine Neumayer, Steffen Mieske, Igor Chilingarian, Christopher Ahn, Holger Baumgardt, Michael Hilker, Dieu Nguyen, Aaron J. Romanowsky, Jonelle Walsh, Mark den Brok, Jay Strader 2018 University of Utah

Upper Limits On The Presence Of Central Massive Black Holes In Two Ultra-Compact Dwarf Galaxies In Centaurus A, Karina Voggel, Anil Seth, Nadine Neumayer, Steffen Mieske, Igor Chilingarian, Christopher Ahn, Holger Baumgardt, Michael Hilker, Dieu Nguyen, Aaron J. Romanowsky, Jonelle Walsh, Mark Den Brok, Jay Strader

Faculty Publications

The recent discovery of massive black holes (BHs) in the centers of high-mass ultra-compact dwarf galaxies (UCDs) suggests that at least some are the stripped nuclear star clusters of dwarf galaxies. We present the first study that investigates whether such massive BHs, and therefore stripped nuclei, also exist in low-mass (M < 107 M ⊙) UCDs. We constrain the BH masses of two UCDs located in Centaurus A (UCD 320 and UCD 330) using Jeans modeling of the resolved stellar kinematics from adaptive optics data obtained with the SINFONI integral field spectrograph at the Very Large Telescope (VLT/SINFONI). No massive BHs are ...


Upper Limits On The Presence Of Central Massive Black Holes In Two Ultra-Compact Dwarf Galaxies In Centaurus A, Karina T. Voggel, Anil C. Seth, Nadine Neumayer, Steffen Mieske, Igor Chilingarian, Christopher P. Ahn, Holger Baumgardt, Michael Hilker, Dieu D. Nguyen, Aaron J. Romanowsky, Jonelle L. Walsh, Mark den Brok, Jay Strader 2018 University of Utah

Upper Limits On The Presence Of Central Massive Black Holes In Two Ultra-Compact Dwarf Galaxies In Centaurus A, Karina T. Voggel, Anil C. Seth, Nadine Neumayer, Steffen Mieske, Igor Chilingarian, Christopher P. Ahn, Holger Baumgardt, Michael Hilker, Dieu D. Nguyen, Aaron J. Romanowsky, Jonelle L. Walsh, Mark Den Brok, Jay Strader

Aaron J. Romanowsky

The recent discovery of massive black holes (BHs) in the centers of high-mass ultra-compact dwarf galaxies (UCDs) suggests that at least some are the stripped nuclear star clusters of dwarf galaxies. We present the first study that investigates whether such massive BHs, and therefore stripped nuclei, also exist in low-mass (M < 107 M ) UCDs. We constrain the BH masses of two UCDs located in Centaurus A (UCD 320 and UCD 330) using Jeans modeling of the resolved stellar kinematics from adaptive optics data obtained with the SINFONI integral field spectrograph at the Very Large Telescope (VLT/SINFONI). No massive ...


Seeing An Exoplanet, Leo Moraczewski 2018 College of Saint Benedict/Saint John's University

Seeing An Exoplanet, Leo Moraczewski

Celebrating Scholarship and Creativity Day

In my experiment, I used the telescopes at the Saint John’s Observatory to measure the brightness of three stars that were expected to have exoplanets orbiting them. I was unable to take enough data on two of the stars, but was able to confirm the existence of an exoplanet around the third, HD189733.


Lunar Ice Cube: Development Of A Numerical Model For Attitude Control, Alexander Roberts, Benjamin Malphrus, Kevin Brown 2018 Morehead State University

Lunar Ice Cube: Development Of A Numerical Model For Attitude Control, Alexander Roberts, Benjamin Malphrus, Kevin Brown

Celebration of Student Scholarship Posters Archive

No abstract provided.


Msu And Citizen Cate: A High Definition Look At The Sun’S Inner Corona During The 2017 Solar Eclipse Over Hopkinsville, Kentucky., Jessie Anderson, Ethan Caudill 2018 Morehead State University

Msu And Citizen Cate: A High Definition Look At The Sun’S Inner Corona During The 2017 Solar Eclipse Over Hopkinsville, Kentucky., Jessie Anderson, Ethan Caudill

Celebration of Student Scholarship Posters Archive

No abstract provided.


Physics 516: Electromagnetic Phenomena (Spring 2018), Philip C. Nelson 2018 University of Pennsylvania

Physics 516: Electromagnetic Phenomena (Spring 2018), 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.


Primordial Black Hole Atoms, David Zwick, Tyler Hanover, Brian Nepper 2018 Rowan University

Primordial Black Hole Atoms, David Zwick, Tyler Hanover, Brian Nepper

Student Research Symposium Posters

Primordial black holes are thought to have been formed at the early stages of the universe in the presence of non-homogeneous density distributions of dark matter. We are working under the assumption that dark matter consists of elementary low mass particles, specifically, spin 1/2 fermions. We further assume that dark matter is electrically neutral, thus its main interaction is gravitational. We investigate dark matter spin 1/2 fermions in orbit around a black hole atom and consider mass ranges for which the quantum description is appropriate. Solutions to the Dirac equation are utilized to describe the radial mass distribution ...


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