Maximum Mass Restraint Of Neutron Stars: Quarks, Pion, Kaons, And Hyperons, 2017 Claremont McKenna College
Maximum Mass Restraint Of Neutron Stars: Quarks, Pion, Kaons, And Hyperons, Garrett Ryan
CMC Senior Theses
This thesis explores the topic of maximum mass stability of neutron stars. The outer structure is detailed and explores nuclear pasta phases, the neutron drip line, and density transitions of matter in the crust and atmosphere layers. Other discussion points include superfluids in the crust and core, vortex roles in neutron stars, and magnetic field effects on the EOS in neutron stars. The inner core is studied in much more detail due to its significant role in EOS. The variety of stars include pion condensate stars, kaon condensate stars, npeu stars, npeu stars with the inclusion of hyperons, quark-hybrid stars ...
The Subject Librarian Newsletter, Nanoscience, Fall 2016, 2016 University of Central Florida
The Subject Librarian Newsletter, Nanoscience, Fall 2016, Sandy Avila
No abstract provided.
Observations And Light Curve Analysis Of Transiting Extra-Solar Planets, 2016 Stephen F Austin State University
Observations And Light Curve Analysis Of Transiting Extra-Solar Planets, Clark M. Holcomb
Electronic Theses and Dissertations
The purpose of this research was to perform the procedures to study transiting exoplanets in their entirety, from the data collection process to determining physical characteristics and orbital properties. The research was conducted with two telescopes of different sizes (16” and 12”) at multiple sites in order to refine the detection process. Both Maxim DL and Mira Pro x64 software were used to process the resulting images. The PHOEBE program was used to model the data to determine the properties of the exoplanets, which were then compared to the results obtained by other astronomers. The data collection process as well ...
Elasticity Of Cylindrical Black Holes, 2016 California Polytechnic State University, San Luis Obispo
Elasticity Of Cylindrical Black Holes, Conrad Pearson
Black holes are regions of strong gravity, and are often regarded as behaving like drops of fluid. When this line of thought is applied to cylindrical black holes (black cylinders), a mapping can be made between known instabilities for black cylinders and ordinary fluid cylinders. However, this known correlation is increasingly less accurate for lower spatial dimensions, and I seek to correct this discrepancy in this thesis. By considering soft solids instead of pure fluids, elastic energy can be included, which brings us closer to a direct comparison. In improving this mapping, it becomes possible to better understand the behavior ...
Cryogenic Viscous Liquids On Icy Moons, 2016 University of Arkansas, Fayetteville
Cryogenic Viscous Liquids On Icy Moons, Danielle Neighbour
Civil Engineering Undergraduate Honors Theses
The study of cryogenically viscous liquids such as methane and ethane offers critical insight into the behavior of fluids on icy moons such as Saturn’s moon Titan. Shrouded by a hazy hydrocarbon shield, Titan’s significant nitrogen atmosphere of 1.5 bar, methane-driven hydrological cycle, and lakes and rivers are vaguely similar to our Earthly home. The European-created Huygens probe, carried by the Cassini spacecraft, arrived on Titan’s surface in January 2005 . Upon landing, Huygens photographed its landing site, as seen in Figure 1. The photo depicts rock like objects, thought to be comprised of water ice ...
Direct Band Gap Measurements, 2016 Brigham Young University - Provo
Direct Band Gap Measurements, John Ryan Peterson
All Student Publications
This presentation was given during the summer of 2016 as part of the BYU REU program funded by the NSF. Here I give a brief explanation of our quantum dot synthesis and then explain the mechanism of photoluminsecence used to measure indirect band gap energies of semiconductors. Our experimental setup is shown. Direct band gaps of lead sulfide quantum dots synthesized in ferritin are reported. The data show that the band gap can be tuned arbitrarily in a certain range by varying the concentrations of the reactants. We compare stability of quantum dots in ferritin to quantum dots synthesized without ...
Determining The Index Of Refraction Of Aluminum Fluoride In The Ultra Violet Spectrum, 2016 Brigham Young University
Determining The Index Of Refraction Of Aluminum Fluoride In The Ultra Violet Spectrum, Zoe Hughes
All Student Publications
A NASA project called Large UV/Optical/Infrared Surveyor (LUVOIR) is looking into ways to coat a mirror for a new space telescope. We contributed to this project by investigating aluminum fluoride (AlF3) as a possible coating for the mirror. We measured the index of refraction of AlF3 in the wavelength range 6 – 49.5 nm by testing three sample mirrors, each made up of a silicon wafer with a coating of AlF3. We took data at the Advanced Light Source (ALS) in Berkeley, California and in the laboratory at Brigham Young University (BYU). There are discrepancies ...
Quantum Dot Band Gap Measurements, 2016 Brigham Young University - Provo
Quantum Dot Band Gap Measurements, John Ryan Peterson
All Student Publications
This presentation was given during the summer of 2016 as part of the BYU REU program funded by the NSF. Here I give a brief explanation of our quantum dot synthesis as well as explain the use of absorption spectroscopy to measure indirect band gap energies of semiconductors. Our experimental setup is shown and recent improvements are explained. We report indirect band gaps of quantum dots containing varying amounts of cobalt oxide and manganese oxide and synthesized in the protein ferritin. The data show that the band gap can be tuned arbitrarily in a certain range by varying the concentrations ...
The Sdss–2mass–Wise 10 Dimensional Stellar Color Locus, 2016 Western Washington University
The Sdss–2mass–Wise 10 Dimensional Stellar Color Locus, James R. A. Davenport, Željko Ivezić, Andrew C. Becker, John J. Ruan, Nicholas M. Hunt-Walker, Kevin R. Covey, Alexia R. Lewis, Yusra Alsayyad, Lauren M. Anderson
We present the fiducial main-sequence stellar locus traced by 10 photometric colours observed by Sloan Digital Sky Survey (SDSS), Two Micron All Sky Survey (2MASS), and Wide-field Infrared Survey Explorer(WISE). Median colours are determined using 1052 793 stars with r-band extinction less than 0.125. We use this locus to measure the dust extinction curve relative to the r band, which is consistent with previous measurements in the SDSS and 2MASS bands. The WISE band extinction coefficients are larger than predicted by standard extinction models. Using 13 lines of sight, we find variations in the extinction curve in H ...
Improved Photometric Calibrations For Red Stars Observed With The Sdss Photometric Telescope, 2016 Western Washington University
Improved Photometric Calibrations For Red Stars Observed With The Sdss Photometric Telescope, James R. A. Davenport, John J. Bochanski, Kevin R. Covey, Suzanne L. Hawley, Andrew A. West, Doanld P. Schneider
We present a new set of photometric transformations for red stars observed with the Sloan Digital Sky Survey (SDSS) 0.5 m Photometric Telescope (PT) and the SDSS 2.5 m telescope at the Apache Point Observatory in New Mexico. Nightly PT observations of US Naval Observatory standards are used to determine extinction corrections and calibration terms for SDSS 2.5 m photometry. Systematic differences between the PT and native SDSS 2.5 m ugriz photometry require conversions between the two systems which have previously been undefined for the reddest stars. By matching ~43,000 stars observed with both the ...
Death Of A Cluster: The Destruction Of M67 As Seen By The Sloan Digital Sky Survey, 2016 Western Washington University
Death Of A Cluster: The Destruction Of M67 As Seen By The Sloan Digital Sky Survey, James R. A. Davenport, Eric L. Sandquist
We probe the spatial and dynamical structure of the old open cluster M67 using photometric data from the Sloan Digital Sky Survey's sixth data release. Making use of an optimal contrast, or matched filter, algorithm, we map the distribution of high probability members of M67. We find an extended and elongated halo of likely members to a radius of nearly 60'. Our measured core radius of R core = 824 ± 060 is somewhat larger than that of previous estimates. We attribute the larger core radius measurement to the SDSS probing lower mass main sequence stars than has been done before ...
Kepler Flares Ii: The Temporal Morphology Of White-Light Flares On Gj 1243, 2016 Western Washington University
Kepler Flares Ii: The Temporal Morphology Of White-Light Flares On Gj 1243, James R. A. Davenport, Suzanne L. Hawley, Leslie Hebb, John P. Wisniewski, Adam F. Kowalski, Emily C. Johnson, Michael Malatesta, Jesus Paraza, Marcus Keil, Steven M. Silverberg, Tiffany C. Jansen, Matthew S. Scheffler, Jodi R. Berdis, Daniel M. Larsen, Eric J. Hilton
We present the largest sample of flares ever compiled for a single M dwarf, the active M4 star GJ 1243. Over 6100 individual flare events, with energies ranging from 1029 to 1033 erg, are found in 11 months of 1 minute cadence data from Kepler. This sample is unique for its completeness and dynamic range. We have developed automated tools for finding flares in short-cadence Kepler light curves, and performed extensive validation and classification of the sample by eye. From this pristine sample of flares we generate a median flare template. This template shows that two exponential cooling ...
Sdss J14584479+3720215: A Benchmark Jhks Blazar Light Curve From The 2mass Calibration Scans, 2016 Western Washington University
Sdss J14584479+3720215: A Benchmark Jhks Blazar Light Curve From The 2mass Calibration Scans, James R. A. Davenport, John J. Ruan, Andrew C. Becker, Chelsea L. Macleod, Roc M. Cutri
Active galactic nuclei (AGNs) are well-known to exhibit flux variability across a wide range of wavelength regimes, but the precise origin of the variability at different wavelengths remains unclear. To investigate the relatively unexplored near-IR (NIR) variability of the most luminous AGNs, we conduct a search for variability using well sampled JHKs-band light curves from the Two Micron All Sky Survey (2MASS) calibration fields. Our sample includes 27 known quasars with an average of 924 epochs of observation over three years, as well as one spectroscopically confirmed blazar (SDSS J14584479+3720215) with 1972 epochs of data. This is the best-sampled ...
The Kepler Catalog Of Stellar Flares, 2016 Western Washington University
The Kepler Catalog Of Stellar Flares, James R. A. Davenport
A homogeneous search for stellar flares has been performed using every available Kepler light curve. An iterative light curve de-trending approach was used to filter out both astrophysical and systematic variability to detect flares. The flare recovery completeness has also been computed throughout each light curve using artificial flare injection tests, and the tools for this work have been made publicly available. The final sample contains 851,168 candidate flare events recovered above the 68% completeness threshold, which were detected from 4041 stars, or 1.9% of the stars in the Kepler database. The average flare energy detected is ~1035 ...
Multi-Wavelength Characterization Of Stellar Flares On Low-Mass Stars Using Sdss And 2mass Time Domain Surveys, 2016 Western Washington University
Multi-Wavelength Characterization Of Stellar Flares On Low-Mass Stars Using Sdss And 2mass Time Domain Surveys, James R. A. Davenport, Andrew C. Becker, Adam F. Kowalski, Suzanne L. Hawley, Sarah J. Schmidt, Eric J. Hilton, Branimir Sesar, Roc Cutri
We present the first rates of flares from M dwarf stars in both red optical and near-infrared (NIR) filters. We have studied ~50,000 M dwarfs from the Sloan Digital Sky Survey (SDSS) Stripe 82 area and 1321 M dwarfs from the Two Micron All Sky Survey (2MASS) Calibration Scan Point Source Working Database that overlap SDSS imaging fields. We assign photometric spectral types from M0 to M6 using (r – i) and (i – z) colors for every star in our sample. Stripe 82 stars each have 50-100 epochs of data, while 2MASS Calibration stars have ~1900 epochs. From these data ...
Detecting Differential Rotation And Starspot Evolution On The M Dwarf Gj 1243 With Kepler, 2016 Western Washington University
Detecting Differential Rotation And Starspot Evolution On The M Dwarf Gj 1243 With Kepler, James R. A. Davenport, Leslie Hebb, Suzanne L. Hawley
We present an analysis of the starspots on the active M4 dwarf GJ 1243, using 4 years of time series photometry from Kepler. A rapid P = 0.592596 ± 0.00021 days rotation period is measured due to the ~2.2% starspot-induced flux modulations in the light curve. We first use a light curve modeling approach, using a Monte Carlo Markov Chain sampler to solve for the longitudes and radii of the two spots within 5 day windows of data. Within each window of time the starspots are assumed to be unchanging. Only a weak constraint on the starspot latitudes can ...
The Very Short Period M Dwarf Binary Sdss J001641–000925, 2016 Western Washington University
The Very Short Period M Dwarf Binary Sdss J001641–000925, James R. A. Davenport, Andrew C. Becker, Andrew A. West, John J. Bochanski, Suzanne L. Hawley, Jon Holtzman, Heather C. Gunning, Eric J. Hilton, Ferah A. Munshi, Meagan Albright
We present follow-up observations and analysis of the recently discovered short period low-mass eclipsing binary, SDSS J001641–000925. With an orbital period of 0.19856 days, this system has one of the shortest known periods for an M dwarf binary system. Medium-resolution spectroscopy and multi-band photometry for the system are presented. Markov Chain Monte Carlo modeling of the light curves and radial velocities yields estimated masses for the stars of M 1 = 0.54 ± 0.07 M ☉ and M 2 = 0.34 ± 0.04 M ☉, and radii of R 1 = 0.68 ± 0.03 R ☉ and R 2 = 0.58 ...
Most Observations Of Our Nearest Neighbor: Flares On Proxima Centauri, 2016 Western Washington University
Most Observations Of Our Nearest Neighbor: Flares On Proxima Centauri, James R. A. Davenport, David M. Kipping, Dimitar Sasselov, Jaymie M. Matthews, Chris Cameron
We present a study of white-light flares from the active M5.5 dwarf Proxima Centauri using the Canadian microsatellite Microvariability and Oscillations of STars. Using 37.6 days of monitoring data from 2014 to 2015, we have detected 66 individual flare events, the largest number of white-light flares observed to date on Proxima Cen. Flare energies in our sample range from 1029 to 1031.5erg. The flare rate is lower than that of other classic flare stars of a similar spectral type, such as UV Ceti, which may indicate Proxima Cen had a higher flare rate in ...
Commercial Space Situational Awareness (Ssa) Capabilities And Their Benefits For Civilian Space Traffic Management (Stm), Mark A. Skinner
Space Traffic Management Conference
Paralleling (but lagging) satellite development, SSA, long the sole domain of sophisticated militaries, now includes commercial providers. These commercial capabilities, identified as beneficial to the sustainable use of outer space, have demonstrated technical sophistication sufficient to positively contribute to the mitigation of satellite interference and provide actionable SSA information. Utilizing small optical telescopes, these entities are able to determine the orbits of objects in the geosynchronous orbit (GSO) to sizes as small as 1 m2, with measured positional uncertainties of 10s of meters, on the order of the size of a modern communications satellite. These techniques can benefit ...
Rainich Conditions In (2+1)-Dimensional Gravity, 2016 Selected Works