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Milky Way Tomography With K And M Dwarf Stars: The Vertical Structure Of The Galactic Disk, Deborah Ferguson, Susan Gardner, Brian Yanny 2017 University of Kentucky

Milky Way Tomography With K And M Dwarf Stars: The Vertical Structure Of The Galactic Disk, Deborah Ferguson, Susan Gardner, Brian Yanny

Physics and Astronomy Faculty Publications

We use the number density distributions of K and M dwarf stars with vertical height from the Galactic disk, determined using observations from the Sloan Digital Sky Survey, to probe the structure of the Milky Way disk across the survey's footprint. Using photometric parallax as a distance estimator we analyze a sample of several million disk stars in matching footprints above and below the Galactic plane, and we determine the location and extent of vertical asymmetries in the number counts in a variety of thin- and thick-disk subsamples in regions of some 200 square degrees within 2 kpc in ...


Photoelectric Magnitude Measurements Of The Lunar Eclipses On May 16, 2003 And Oct. 28, 2004, Richard W. Schmude Jr. 2017 Gordon State College

Photoelectric Magnitude Measurements Of The Lunar Eclipses On May 16, 2003 And Oct. 28, 2004, Richard W. Schmude Jr.

Georgia Journal of Science

The Moon's brightness dropped by 10.73 ± 0.07 and 10.61 ± 0.15 magnitudes during the total lunar eclipses on May 16, 2003 and Oct. 28, 2004 respectively. These magnitude drops are close to the corresponding value for the Jan., 2000 total lunar eclipse and indi­cate that not much change in the transparency of the atmosphere has occurred in the last 4 years.


Shakespeare, A Supernova, And A Little Green Man Walk Into A Mathematics Classroom, Sheila Kirstin Miller 2017 City University of New York

Shakespeare, A Supernova, And A Little Green Man Walk Into A Mathematics Classroom, Sheila Kirstin Miller

Journal of Humanistic Mathematics

Creativity amidst constraints is a hallmark of the STEM researcher. It is precisely what is required to see what has never been seen. It is also at the core of creative mathematics, more commonly called “research”. We in the 21st century tell ourselves that science and story are separate enterprises. One goal of this article is to tell parts of the human story—featuring Shakespeare, Tycho Brahe, visiting stars, Little Green Men, and modern astrophysics—that might erode belief in that duality and illustrate why dissolving the artificial barriers between talents within individuals is to the benefit of ourselves ...


Wideband Photometry Of Saturn In 2004-2005, Richard W. Schmude Jr. 2017 Gordon State College

Wideband Photometry Of Saturn In 2004-2005, Richard W. Schmude Jr.

Georgia Journal of Science

The writer made 60 photometric measurements of Saturn + rings between Nov. 5, 2004 and Jan. 21, 2005. The normalized magnitudes of Saturn for a ring tilt angle of 22° are B(1,0) = -8.55 ± 0.01, V(1,0) = -9.60 ± 0.01, B(1,0) = -10.27 ± 0.01, and I(1,0) = -10. 4 7 ± 0.01; the corresponding solar phase angle coefficients are cB = 0.027 ± 0.006, cV = 0.021 ± 0.005, cB = 0.020 ± 0.005, and cB = 0.022 ± 0.005. The 2005 opposition surge values (in magnitudes at ...


Wideband Photometric Magnitude Measurements Of Saturn Made During The 2005-06 Apparition, Richard W. Schmude Jr. 2017 Gordon State College

Wideband Photometric Magnitude Measurements Of Saturn Made During The 2005-06 Apparition, Richard W. Schmude Jr.

Georgia Journal of Science

The writer made 37 brightness measurements of Saturn + rings between Nov. 3, 2005 and March 16, 2006 using the B (blue), V (green), R (red), and I (infrared) filters. The selected normalized magnitudes of Saturn at a ring tilt angle of 18° are: B(1,0) = - 8.43 ± 0.03, V(1,0) = -9.48 ± 0.02, R(1,0) = -10.16 ± 0.04, and 1(1,0) = -10.28 ± 0.02. The selected phase angle coefficients of Saturn, in magnitudes/degree, are: cB = 0.022 ± 0.014, cV = 0.021 ± 0.008, cR = 0.027 ± 0 ...


Wideband Photometry Of Saturn In 2006-2007, Richard W. Schmude Jr. 2017 Gordon State College

Wideband Photometry Of Saturn In 2006-2007, Richard W. Schmude Jr.

Georgia Journal of Science

The writer carried out brightness measurements of Saturn and its rings with four different color filters. The selected normalized mag­nitudes of Saturn + rings for a ring tilt angle of 14° are B(1,0) = -8.25 ± 0.03, V(1,0) = -9.36 ± 0.03, R(1,0) = -10.01 ± 0.04 and 1(1,0) -10.16 ± 0.04. The opposition surge values for Saturn+ rings on Feb. 11, 2007 (solar phase angle = 0.15°) were 0.19 and 0.06 magnitudes for the Band V filters respectively. The writer concludes that the B-V and V-R color indexes ...


The Sluggs Survey: Dark Matter Fractions At Large Radii And Assembly Epochs Of Early-Type Galaxies From Globular Cluster Kinematics, Adebusola Alabi, Duncan Forbes, Aaron Romanowsky, Jean Brodie, Jay Strader, Joachim Janz, Christopher Usher, Lee Spitler, Sabine Bellstedt, Anna Ferré-Mateu 2017 Swinburne University of Technology

The Sluggs Survey: Dark Matter Fractions At Large Radii And Assembly Epochs Of Early-Type Galaxies From Globular Cluster Kinematics, Adebusola Alabi, Duncan Forbes, Aaron Romanowsky, Jean Brodie, Jay Strader, Joachim Janz, Christopher Usher, Lee Spitler, Sabine Bellstedt, Anna Ferré-Mateu

Faculty Publications

We use globular cluster kinematics data, primarily from the SAGES Legacy Unifying Globulars and GalaxieS (SLUGGS) survey, to measure the dark matter fraction (fDM) and the average dark matter density (〈ρDM〉) within the inner 5 effective radii (Re) for 32 nearby early-type galaxies (ETGs) with stellar mass log (M*/M⊙) ranging from 10.1 to 11.8. We compare our results with a simple galaxy model based on scaling relations as well as with cosmological hydrodynamical simulations where the dark matter profile has been modified through various physical processes. We find a high fDM (≥0.6) within 5 Re in ...


The Sluggs Survey: Dark Matter Fractions At Large Radii And Assembly Epochs Of Early-Type Galaxies From Globular Cluster Kinematics, Adebusola B. Alabi, Duncan A. Forbes, Aaron J. Romanowsky, Jean P. Brodie, Jay Strader, Joachim Janz, Christopher Usher, Lee R. Spitler, Sabine Bellstedt, Anna Ferré-Mateu 2017 Swinburne University of Technology

The Sluggs Survey: Dark Matter Fractions At Large Radii And Assembly Epochs Of Early-Type Galaxies From Globular Cluster Kinematics, Adebusola B. Alabi, Duncan A. Forbes, Aaron J. Romanowsky, Jean P. Brodie, Jay Strader, Joachim Janz, Christopher Usher, Lee R. Spitler, Sabine Bellstedt, Anna Ferré-Mateu

Aaron J. Romanowsky

We use globular cluster kinematics data, primarily from the SAGES Legacy Unifying Globulars and GalaxieS (SLUGGS) survey, to measure the dark matter fraction (fDM) and the average dark matter density (〈ρDM〉) within the inner 5 effective radii (Re) for 32 nearby early-type galaxies (ETGs) with stellar mass log (M*/M⊙) ranging from 10.1 to 11.8. We compare our results with a simple galaxy model based on scaling relations as well as with cosmological hydrodynamical simulations where the dark matter profile has been modified through various physical processes. We find a high fDM (≥0.6) within 5 ...


Wideband Photometry Of Saturn In 2007-2008, Richard W. Schmude Jr. 2017 Gordon State College

Wideband Photometry Of Saturn In 2007-2008, Richard W. Schmude Jr.

Georgia Journal of Science

The writer made 45 brightness measurements of Saturn + rings between Nov. 28, 2007 and April 24, 2008. The selected B(1,0), V(1,0), R(1,0) and I(1,0) values for Saturn + rings for b = 7° are: -8.10 ± 0.01, -9.14 ± 0.01, -9.77 ± 0.01 and -9.87 ± 0.02 respectively. The selected solar phase angle coefficients (in magnitudes/degree) are: 0.041 ± 0.006, 0.034 ± 0.005, 0.022 ± 0.007 and 0.027 ± 0.007 respectively. It is concluded that the angle between the ring plane and the Sun (B ...


Wideband Photometry Of Saturn In 2008-2009, Richard W. Schmude Jr. 2017 Gordon State College

Wideband Photometry Of Saturn In 2008-2009, Richard W. Schmude Jr.

Georgia Journal of Science

A total of 52 brightness measurements of Saturn were made during its 2008-2009 apparition. (An apparition is the time interval between when the planet is in conjunction with the Sun to the next time that it is conjunction with the Sun.) The selected normalized magnitudes of Saturn for b = 3.0° are B(1,0) = -7.87 ± 0.02, V(1,0) = - 9.00 ± 0.01, R(1,0) = -9.62 ± 0.01 and I(1,0) = -9.63 ± 0.01. (I have defined b as the square root of the absolute value of the product of the Saturnicentric latitude ...


Full-Disk Wideband Photometry Of The Moon: R And I Filter Measurements, Richard W. Schmude Jr. 2017 Gordon State College

Full-Disk Wideband Photometry Of The Moon: R And I Filter Measurements, Richard W. Schmude Jr.

Georgia Journal of Science

A total of 42 full-disk brightness measurements of our Moon are reported. These measurements include the entire lunar disk including the Earthlit portion. All measurements were made on the Johnson R (red) and I (infrared) system and were fitted to cubic equations. The results are summarized in this report. The selected normalized magnitudes of the Moon are R(1,0) = -0.70 ± 0.10 and I(1,0) = -1.12 ± 0.06. The selected geometric albedo is 0.18 ± 0.01 for the Johnson R and I system.


Some Recent Studies Of Mars: The North Polar Cap, Cecropia And Hellas, Richard W. Schmude Jr. 2017 Gordon State College

Some Recent Studies Of Mars: The North Polar Cap, Cecropia And Hellas, Richard W. Schmude Jr.

Georgia Journal of Science

This paper summarizes changes on Mars which occurred in 2014. Images recorded by the Mars Reconnaissance Orbiter’s MARCI camera (hereafter MRO) and those made from the Earth are examined. It is concluded a spiral-shaped cloud of water ice crystals developed and moved eastward at an average speed of 1.7 m/s, a temporary isolated bright patch in Cecropia developed and one or more dust storms developed at the NPC edge near 83° N, 320° W. Measurements of the boundary of a white area in Hellas are consistent with it not changing as the year, season or time of ...


The North Polar Cap Of Mars, Richard W. Schmude Jr. 2017 Gordon State College

The North Polar Cap Of Mars, Richard W. Schmude Jr.

Georgia Journal of Science

During late 2013 and early 2014, the Northern Hemisphere of Mars faced Earth. This provided a prime opportunity for studying its North Polar Cap (NPC). The writer measured the cap size during the intervals 30° < Ls < 70° and 82° < Ls < 134°. (The areocentric longitude of the Sun from Mars is designated as Ls and it determines the seasons on that planet; essentially, the beginning of the northern spring, summer, fall and winter are at Ls = 0°, 90°, 180° and 270°). NPC latitude measurements were made with the software package WinJupos. The mean latitudes were measured for 23 four-degree intervals of Ls. Wilcoxon Signed Rank Tests at the 90% confidence level are consistent with there being no statistical difference between the NPC in 2000 and both 2013 and 2011-2012 for 30° < Ls < 70°. Based on this same test there is a statistical difference for the NPC in 2002 and 2009-2010 compared to 2000. Therefore, it is concluded that the NPC may show interannual differences. Essentially, the NPC stopped shrinking at Ls = 82°. Its mean latitude ...


Introduction To Classical Field Theory, Charles G. Torre 2017 Department of Physics, Utah State University

Introduction To Classical Field Theory, Charles G. Torre

Charles G. Torre

This is an introduction to classical field theory. Topics treated include: Klein-Gordon field, electromagnetic field, scalar electrodynamics, Dirac field, Yang-Mills field, gravitational field, Noether theorems relating symmetries and conservation laws, spontaneous symmetry breaking, Lagrangian and Hamiltonian formalisms. This is version 1.1, released in June 2017.


Searching For Signals Of Dark Matter Decay, Gardner R. Marshall, William Hester 2017 The College of Charleston

Searching For Signals Of Dark Matter Decay, Gardner R. Marshall, William Hester

Journal of the South Carolina Academy of Science

Dark matter is believed to make up approximately eighty-three percent of the matter in the universe. Despite its apparent abundance, it has not yet been directly detected, and it is not known what types of particles it is composed of. Efforts to understand what dark matter is made of and how it fits into the Standard Model of particle physics is currently an important and active area of research. In this paper we investigate a method of studying dark matter indirectly by using terrestrial neutrino telescopes to search for signs of dark matter decay. In particular, we study leptonically decaying ...


Characterizing Cool Brown Dwarfs And Low-Mass Companions With Low-Resolution Near-Infrared Spectra, Paige Godfrey 2017 The Graduate Center, City University of New York

Characterizing Cool Brown Dwarfs And Low-Mass Companions With Low-Resolution Near-Infrared Spectra, Paige Godfrey

All Graduate Works by Year: Dissertations, Theses, and Capstone Projects

Exoplanet direct detections are reaching the temperature regime of cool brown dwarfs, motivating further understanding of the coolest substellar atmospheres. These objects, T and Y dwarfs, are numerous and isolated in the field, thus making them easier to study in detail than objects in companion systems. Brown dwarf spectral types are derived from spectral morphology and generally appear to correspond with decreasing mass and effective temperature (Teff). However, spectral subclasses of the colder objects do not share this monotonic temperature correlation, indicating that secondary parameters (gravity, metallicity, dust) significantly influence spectral morphology. These secondary atmospheric parameters can provide insight ...


Sobel, Dava. The Glass Universe: How The Ladies Of The Harvard Observatory Took The Measure Of The Stars. New York: Viking, 2016. 324 Pp. $30.00 Hardcover (Isbn 9780670016952)., Aldemaro Romero Jr. 2017 CUNY Bernard M Baruch College

Sobel, Dava. The Glass Universe: How The Ladies Of The Harvard Observatory Took The Measure Of The Stars. New York: Viking, 2016. 324 Pp. $30.00 Hardcover (Isbn 9780670016952)., Aldemaro Romero Jr.

Publications and Research

Women in science have been and are still facing numerous obstacles. According

to the American Association of University Professors, despite the fact that 60

percent of all doctoral students (the main pipeline for academia) in this country

are women, only 46 percent of assistant professors, 38 percent of associate

professors, and 23 percent of full professors are female. On top of that, women

faculty in colleges and universities in the United States earn on average 10 percent

less than their male counterparts.1 A number of studies have shown that women

in academia suffer from lower expectations for intelligence, so ...


The Sluggs Survey: Using Extended Stellar Kinematics To Disentangle The Formation Histories Of Low-Mass S0 Galaxies, Sabine Bellstedt, Duncan Forbes, Caroline Foster, Aaron Romanowsky, Jean Brodie, Nicola Pastorello, Adebusola Alabi, Alexa Villaume 2017 Swinburne University of Technology

The Sluggs Survey: Using Extended Stellar Kinematics To Disentangle The Formation Histories Of Low-Mass S0 Galaxies, Sabine Bellstedt, Duncan Forbes, Caroline Foster, Aaron Romanowsky, Jean Brodie, Nicola Pastorello, Adebusola Alabi, Alexa Villaume

Faculty Publications

We utilize the DEIMOS instrument on the Keck telescope to measure the wide-field stellar kinematics of early-type galaxies as part of the SAGES Legacy Unifying Globulars and GalaxieS (SLUGGS) survey. In this paper, we focus on some of the lowest stellar mass lenticular galaxies within this survey, namely NGC 2549, NGC 4474, NGC 4459 and NGC 7457, performing detailed kinematic analyses out to large radial distances of ∼2–3 effective radii. For NGC 2549, we present the first analysis of data taken with the SuperSKiMS (Stellar Kinematics from Multiple Slits) technique. To better probe kinematic variations in the outskirts of ...


Book Review: Shoot The Moon: A Complete Guide To Lunar Imaging, T. D. Oswalt 2017 Embry-Riddle Aeronautical University

Book Review: Shoot The Moon: A Complete Guide To Lunar Imaging, T. D. Oswalt

Publications

This document is Dr. Oswalt’s review of Shoot the Moon: a Complete Guide to Lunar Imaging by Dupont-Bloch, Nicolas. Cambridge, 2016, 323 p index, 9781107548442 $39.95, 9781316657867 $32.00.


Active Control Of Cylindrical Shells Using The Weighted Sum Of Spatial Gradients (Wssg) Control Metric, Pegah Aslani 2017 Brigham Young University

Active Control Of Cylindrical Shells Using The Weighted Sum Of Spatial Gradients (Wssg) Control Metric, Pegah Aslani

All Theses and Dissertations

Cylindrical shells are common structures that are often used in industry, such as pipes, ducts, aircraft fuselages, rockets, submarine pressure hulls, electric motors and generators. In many applications it is desired to attenuate the sound radiated from the vibrating structure. There are both active and passive methods to achieve this purpose. However, at low frequencies passive methods are less effective and often an excessive amount of material is needed to achieve acceptable results. There have been a number of works regarding active control methods for this type of structure. In most cases a considerable number of error sensors and secondary ...


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