Bulletin of the American Physical Society
Fall 2014 Joint Meeting of the Texas Section of the APS, Texas Section of the AAPT, and Zone 13 of the Society of Physics Students
Volume 59, Number 12
Friday–Sunday, October 17–19, 2014; College Station, Texas
Session E6: Society of Physics Students |
Hide Abstracts |
Chair: Timothy Head, Abilene Christian University Room: MPHY 213 |
Saturday, October 18, 2014 3:35PM - 3:47PM |
E6.00001: Comparison of CME and CIR driven storms based on observations made by TWINS Bianca Trigo, Gunner Robison, Amy Keesee, Jerry Carr Jr. The analysis of data collected from the TWINS missions for an intense CME driven storm on September 26 2011 and a CIR driven storm on October 13 2012 will be presented. Geomagnetic storms are categorized into two different groups' Coronal mass ejection, CME, and corotating interaction regions, CIR, driven storms. For CME driven storms, there are intense and moderate storms based on their magnetic intensity, moderate is -78Dst anything below is categorized as an intense CME storm driver. [Preview Abstract] |
Saturday, October 18, 2014 3:47PM - 3:59PM |
E6.00002: Reproduction of Heinrich Hertz's Experiment of 1887 Zachary Williams, Hunter Sullivan In 1887, Heinrich Hertz confirmed the transmission of electromagnetic waves, which was theorized by James Clerk Maxwell. In his experiment, Hertz was able to detect and measure the wavelength and frequency of the transmitted wave. Hertz concluded that Maxwell's electromagnetic waves do in fact propagate through space at the speed of light. In this reproduction, a similar model was constructed to detect these electromagnetic waves. The initial design was constructed to confirm consistent successful transmission. This design included a RLC circuit and a one-meter diameter loop detection antenna made from copper tubing. Work is now being performed to measure both the wavelength and frequency in order to confirm the velocity of propagation for electromagnetic waves is the speed of light. [Preview Abstract] |
Saturday, October 18, 2014 3:59PM - 4:11PM |
E6.00003: A Multi-band Extension of the Analysis of Variance Period Finding Algorithm Nicholas Mondrik, Jennifer Marshall, James Long One of the largest challenges facing modern astronomical surveys is the automated classification of sources. In the case of variable stars, periods are among the most useful features for classification algorithms. In surveys such as the Dark Energy Survey, which cover a large area of the sky with relatively few visits, single band period finding algorithms can struggle due to poor phase coverage in any one band. However, these single band algorithms throw away data in the form of other bands that can potentially hold more information about the period of the variable source. We present here an extension of a single band period finding algorithm to include information about the period contained in other bands. We generate light curves of RR Lyrae stars in 5 bands and compare the performance of the multi-band algorithm to its single band implementation. By including these extra bands we show improved performance for poorly sampled light curves over long baselines in simulated data. [Preview Abstract] |
Saturday, October 18, 2014 4:11PM - 4:23PM |
E6.00004: Development of a RF-Driven H-/H$+$ Surface Plasma Ion Source for the Spallation Neutron Source Jeffrey Breitschopf, Jerry Carr Jr., Vadim Dudnikov, Rol Johnson, Robert Welton, Martin Stockli, Sydney Murray, Manuel Santana, Terry Pennisi, Baoxi Han, Chip Piller A Surface Plasma ion Source (SPS) equipped with an external Saddle-type Antenna (SA) powered by 13.56 MHz Radio Frequency (RF) was tested at the Spallation Neutron Source (SNS) test stand at the Oak Ridge National Laboratory. Hydrogen ions were extracted from the source, and modifications were implemented to increase the ion beam output and optimize cooling. The source was tested under a duty factor of 5-100{\%} at 150Hz with power ranging from 0.8 to 3.3 kW. Cesium was also used to optimize the H- beam output. The highest beam current the source produced was 15 mA at 3 kW of RF power with an ion production efficiency of $\sim$ 5 mA/kW. The current ion source at the SNS produces 30-40 mA of H- ($\sim$ 1 mA/kW) of accelerated beam, operating with 50-60 kW of RF power and a duty factor of 6{\%}. Future work will be to test the SA RF SPS under the conditions and requirements of the SNS. The development of alterative sources for the SNS, such as this one, may figure prominently in future facility and reliability upgrades. [Preview Abstract] |
Saturday, October 18, 2014 4:23PM - 4:35PM |
E6.00005: The effect of oxygen vacancies and strain on the optical bandgap of strained SrTiO$_{3}$ thin films Nathan Steinle, Barry Koehne, Ryan Cottier, Daniel Currie, Nikoleta Theodoropoulou SrTiO$_{3}$ (STO) films were grown on single crystal SrTiO$_{3}$ p-Si (001) substrates using molecular beam epitaxy (MBE). The single-phase STO/Si films were of high crystalline quality as verified by x-ray diffraction (XRD) and atomic force microscopy (AFM) with an rms roughness of less than 0.5 nm. Oxygen vacancies were introduced by controlling the oxygen pressure (varied from 10$^{-8}$ to10$^{-7}$ torr) during growth. Both thickness variation and oxygen pressure alter the crystal structure and electronic properties of STO. The lattice mismatch of STO on Si causes a 1.7{\%} bi-axial, compressive strain. The oxygen vacancies cause a tensile strain because of the different Ti$^{3+}$ and Ti$^{4+}$ ionic radii. This agrees with our XRD measurements that show a decrease of the out of plane lattice constant as either the thickness or the oxygen pressure during growth increases. We used a Variable Angle Spectroscopic Ellipsometer M-2000 by Woolam and the VASE software to measure and model the optical properties of the films using Tauc-Lorentz oscillators for the STO layer and directly measured optical properties of Si and STO substrates. Our results show that the indirect bandgap of STO decreases as either the thickness increases or the oxygen vacancies decrease, in agreement with theoretical calculations. [1] [Preview Abstract] |
Saturday, October 18, 2014 4:35PM - 4:47PM |
E6.00006: A comprehensive evaluation of the performance and materials chemistry of a silicone-based replicating compound Michael Kalan, Michael Brumbach The objective of this project was to characterize the performance and chemistry of a silicone-based replicating compound. Some silicone replicating compounds are useful for critical inspection of surface features. Common applications are for examining micro-cracks, surface pitting, scratching, and other surface defects. Materials characterization techniques were used: FTIR, XPS, ToF-SIMS, AFM, and Confocal Microscopy to evaluate the replicating compound. These techniques allowed for the characterization and verification of the resolution capabilities and surface contamination that may be a result of using the compound. The AFM and Confocal Microscopy results showed the compound does accurately replicate the surface features to the claimed resolution. XPS and ToF-SIMS showed there is a silicone contaminant layer left behind when a cured replica is peeled off a surface. Attempts to clean off the contamination could not completely remove all silicone. The methods and results for the compounds will be presented. [Preview Abstract] |
Saturday, October 18, 2014 4:47PM - 4:59PM |
E6.00007: Charging and interaction of two-particle system within a glass box immersed in a low-vacuum argon plasma Michael Hoff Due to Debye screening, the interaction between charged dust particles within a plasma may not be considered as a simple Coulomb force. In order to observe particle interaction, the top particle in a vertical, two-particle chain is pushed from its equilibrium position using a high-power Verdi laser, and as it returns to equilibrium will interact with the second particle. In order to isolate the particle interaction force, the electrostatic force and neutral drag force are subtracted from the net force acting on the particle by using a single particle undergoing damped oscillations in the box as a reference. The net electric field and drag force within the glass box are examined by forcing damped oscillations of a single particle, in the vertical direction by an applied DC bias between electrodes and in the horizontal direction by laser-pushing. It is found that in both the horizontal and vertical dimensions the electric field depends linearly on the particle's distance from its equilibrium position, and the linear coefficient to describe the field in turn has a linear dependence on plasma power. After isolating the particle-particle interaction force, what is expected to be an equal and opposite interaction force between the particles is instead found to be asymmetric, and possible causes for this are discussed. [Preview Abstract] |
Follow Us |
Engage
Become an APS Member |
My APS
Renew Membership |
Information for |
About APSThe American Physical Society (APS) is a non-profit membership organization working to advance the knowledge of physics. |
© 2024 American Physical Society
| All rights reserved | Terms of Use
| Contact Us
Headquarters
1 Physics Ellipse, College Park, MD 20740-3844
(301) 209-3200
Editorial Office
100 Motor Pkwy, Suite 110, Hauppauge, NY 11788
(631) 591-4000
Office of Public Affairs
529 14th St NW, Suite 1050, Washington, D.C. 20045-2001
(202) 662-8700