RESEARCH PRESENTATIONS

Poster Session

Below is a list of posters that will be presented at CUWiP, in alphabetical order by author's last name. When you arrive, you will receive a numbered list of posters - the poster boards in the Atchafalaya Room will also be numbered so you can see where you put up your poster. You will be able to put up your posters starting at 10 am, and they can stay up all Saturday.

Your poster should be printed when you arrive at LSU.  However, if for some reason you need to re-print your poster while in town, you may do so at the following places:

• LSU Library → Contact Hannah Gardiner, , for more information.

• Renaissance Imaging
  2031 Government Street, Baton Rouge, LA - (225) 753-0301

• Office Depot (3 locations in Baton Rouge)

• 3116 College Dr., (225) 927-0034
• 7074 Siegen Lane, (225) 295-0011
• 7979 Florida Blvd., (225) 926-3092

Student Oral Presentations, Sunday January 19, 9:30 - 10:30 AM

• 9:30-10:30 AM (Atchafalaya Room, 339)

• 9:30-9:45 AM - Colleen Lattyak
  "Cosmic Perturbations in Contracting Expanding Phases in the Universe"

• 9:45-10:00 AM - Katya Arquilla
  "Diagnosing Mass Flows Around T Tauri Stars"

• 10:00-10:15 AM - Hannah Gardiner
  "Developing a Position Sensitive Ionization Chamber for ANASEN"

• 10:15-10:30 AM - Ying Wun Yvonne Ng
  "Noise Analysis of the Prototype Gas Electron Multiplier Radiation Detector and its Long Term Behavior Study by Kpix"

List of Posters:

• Katya Arquilla (Oral too)  --  "Diagnosing Mass Flows Around T Tauri Stars"
  Abstract:  T Tauri stars are young, highly-active, cool stars that are in many ways similar to the Sun.  The matter around these stars as they develop can accrete onto the star along its magnetic field lines, get ejected in outflows along the star's poles, or settle into a rotating disk around the star.  This project involves the use of spectroscopy to take a deeper look at what is going on close to the stellar surface.  The analysis of hydrogen emission lines can reveal any anomalies or periodicities that could indicate mass outflows or planet companions.

• Bethany Brockhoeven  --  "CALET: Monte Carlo simulations for the CALET Electron Telescope on the Space Station"
  Abstract: The CALorimetric Electron Telescope (CALET) mission is an international collaboration between Japan, Italy, and the United States designed to explore the High Energy Universe.  The instrument is a large, deep calorimeter designed primarily to measure the spectrum of cosmic ray electrons up to 20 TeV. Additional goals of CALET are to address outstanding questions such as (1) the nature of the sources of high energy particles and photons, (2) the details of particle transport in the Galaxy, and (3) signatures of dark matter, in either the high energy electron or gamma ray spectrum. 
  The US collaboration is participating in the development of the CALET instrument, as well as its testing, pre-launch calibrations, flight operations, flight data processing, and science analysis along with the international CALET team.   One of the main goals of the LSU collaboration is to develop analysis software using IDL that will process CALET flight data for the entire CALET collaboration.  This analysis will then be compared to the ROOT analysis for secondary validation.  An initial simulation has been run for 10,000 events, including energy deposit and timing. Results will be shown demonstrating the energy deposited in individual channels and demonstrating the trigger efficiency and particle identification capabilities.

• Kavindi De Silva  --  "NOVA PERSEI 1901 (GK Per) in Quiescence: 47,000 V Magnitudes from 1916 to 2013 in Johnson B & V"
  Abstract: A nova is a close binary system in which a white dwarf is accreting material that overflows from its companion star, a late-type dwarf star. The nova eruption itself is a thermonuclear runaway of the hydrogen accumulated on the surface of the white dwarf (like a huge hydrogen bomb) . Nova eruptions brighten by ~10,000 times from weeks to months. When the nova system returns back to its quiescent level, the brightness of the optical light from a nova system tracks the rate of flow onto the white dwarf as it changes over the years.  Nova Persei 1901 (GK Per) is among the brightest ever observed. As a result, the literature is full of GK Per magnitudes and fragmentary light curves. The American Association of Variable Star Observers have collected a vast set of V, B, and Visual data that runs from the 1916 to 2013.  Weirdly, around 1948, GK Per started having dwarf nova eruptions, which happens due to the instability in the accretion disk, creating a brightening in the system for a couple of weeks or months. A prominent model, called “Hibernation”, predicts that old nova will fade slowly on the scale of centuries. This prediction has never been tested, but we are able to finally test the claim. Critically we have to convert the old magnitudes to Johnson V. Our light curve (see figure 1) shows a basic decline after ~1950 being consistent with Hibernation. But a severe theoretical problem comes from 1917 -1919 when it was fainter than pre-eruption level and from 1919 to ~1945 when it was brightening. These two results pose a stiff challenge for the theorists. 

• Mia Ferriss  --  "Application of the No-Core Symplectic Shell Model to Beryllium and Carbon Isotopes"
  Abstract: Using a schematic interaction that captures most of the physics of a realistic nuclear interaction and employing only a fraction of the ultra-large model space needed for conventional shell-model calculations, we explore collective and alpha-clustering substructures as part of a comprehensive study of light nuclei with number of particles ranging from 7 to 20.  This is achieved by employing symmetries that dominate the nuclear dynamics. We show a successful application of the model that produces reasonable energy levels as well as additional physical observables. This improves our understanding of nuclear structure and could lead to further applications of the model, particularly to heavier and more complicated nuclei. 

• Hannah Gardiner (Oral too)  --  "Developing a Position Sensitive Ionization Chamber for ANASEN"
  Abstract: The Array for Nuclear Astrophysics Studies with Exotic Nuclei (ANASEN) is a charged-particle detector array developed for reaction studies using radioactive ion beams to help improve understanding of the nuclear reactions important in stellar explosions. A gas-filled ionization chamber with two position-sensitive anode wire grid planes read out in 32 channels, and 12 alternating anode/cathode planes was developed and tested for use with ANASEN to identify the kinematic trajectory and atomic number of recoiling heavy ions by their relative energy loss. The position sensitive grids are arranged perpendicularly to each other in order to determine the x-y position of each ion with better than 4 mm resolution. This ionization chamber was tested using a stable beam of 12C at FSU. We report on the performance of this test experiment and plans for measurements with radioactive ion beams at FSU. Two other versions of the detector have been constructed and are now in place at the National Superconducting Cyclotron Laboratory and at the ATLAS accelerator facility at Argonne National Laboratory.

• Dominique Gautreau  --  "FFLO Pairing Correlations in a Trapped Quasi One Dimensional Fermi Gas"
  Abstract: Recent work has pursued the possibility of a Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) phase of imbalanced Fermi gases in one dimension, in which an imposed population imbalance between two species of interacting fermion leads to spatially-modulated local pairing correlations. While experiments at Rice (Liao et al, Nature 467, 567 (2010)) show consistency with the expected bulk phase diagram using the local density approximation, little is known about how the FFLO pairing correlations will be revealed experimentally. Using a simple variational wavefunction ansatz for the FFLO state of a trapped 1D gas, in which the population imbalance leads to an imbalance in pairing among harmonic oscillator states, we compute predicted experimental signatures of the FFLO phase in a trapped one-dimensional fermionic atomic gas.

• Colleen Lattyak  --  "Nanocomposites for Thermoelectric Materials"
  Abstract: Metamaterials exhibiting complex and unusual electric, magnetic and acoustic behavior have been the focus of intense research lately.  The control and manipulation of thermal energy transport using metamaterials however, remains virtually unexplored.  With respect to power generation using thermoelectric devices, the precise control and guidance of electrical and thermal currents provides the opportunity to substantially increase the efficiency.  While small efficiency increases have been achieved through fundamental physical mechanisms (scattering, band structure, etc.), it is important to go beyond the intrinsic material property approach.  Here we develop the synthesis technique to fabricate bismuth telluride-multiwalled carbon nanotube (MWNT) thin films.  This unique nanocomposite is tailored to exhibit enhanced thermoelectric properties which are fundamental to the development of thermoelectric metamaterials.  Characterization is accomplished with scanning and tunneling electron microscopy which, reveals a uniform dispersion of MWNT’s intertwined with bismuth telluride crystals.  Transport property measurements will follow this work thus allowing a complete thermoelectric performance prediction to be made when integrated into metamaterial structures. 

• Lauren Liegey  --  "Optimization of Photon Activation Analysis for Assay of Ore"
  Abstract: Gold is a valuable metal that just keeps getting harder to find. Gold makes up a tiny percentage of the Earth’s crust, and it is estimated that over 75% of the existing gold has already been mined. As it becomes more and more difficult to find gold, mining corporations are seeking more efficient and precise ways to determine how much gold is in a prospective mining area. This determines whether or not mining the ore there will be profitable, so the methods by which the concentration of gold are determined are very important. A mining operation may take samples of the ore in an area and have them tested for gold by many methods, like Fire Assay, Cyanidation, Floatation, or Gravity Separation. These methods work, but they often completely disintegrate the sample and involve using toxic chemicals. Using Photon Activation Analysis (PAA), a sample of ore can be irradiated, thus transmuting the gold atoms in the sample to another isotope of gold which is radioactive, however, the sample is not visibly disturbed. The whole radioactive sample can then be placed in front of a detector that relays information to a computer program, from which one can determine how much gold is in the sample. The radioactive isotope of gold produced has a half-life of less than a week and can thus be safely handled or returned to the public after a short time. PAA gives a result for the sample as a whole. We hope PAA could be more efficient and give a more precise estimate than other current methods since it does not require the sample to be broken down, homogenized, or otherwise prepared ahead of time and only remains radioactive for a short time after the analysis is performed. It could also be safer, since it involves no caustic or toxic chemicals, and only produces a small, quickly diminishing amount of radiation.

• Katherine Maxwell  --  "Bell Inequalities with Classical Communication"
  Abstract: The set of correlations between two parties using shared randomness and classical communication is considered. This continues the work of Bacon and Toner who described the set with binary input and output settings and one bit of communication, and compared their findings to the set of quantum correlations. The extreme points of the communication polytopes are described, and using computational procedures the Bell Inequalities were found for 3 by 2 input measurement settings and one shared bit of communication. Restricting the communication to be in a fixed direction yields nine Bell Inequalities, while 143 inequalities describe random direction communication. As well, the optimal amount of classical communication needed to simulate the set of all no-signaling correlations is given.

• Lacey Medlock  --  "Improved Trigger Timing"
  Abstract: This poster will provide information about the details of improving the timing of the SeaQuest hodoscope system through the addition of clip lines. It will discuss the usage of hodoscopes as the fast trigger for the experiment, as well as the effects of the addition of a clip line to each of the hodoscopes in all hodoscope arrays.

• Catherine Miller  --  "A Technique for the Measuring the Density of Cancellous Bone using an Ultrasonic Imaging System"
  Abstract: Osteoporosis is a degenerative bone disease that affects millions of Americans.  Osteoporosis causes normally porous bone tissue, called cancellous bone, to become more porous and weak.  It is possible that ultrasonic imaging systems may be used to detect changes in bone density (porosity) caused by osteoporosis.  Methods: Ultrasonic images were acquired from 25 cube shaped specimens of cancellous bone in a water tank using a Terason 2000+ ultrasonic imaging system with a 5 MHz linear array transducer.  Images were analyzed using an image processing program called ImageJ.  Pixel brightness values were plotted as a function of depth in the images of each bone specimen.  Pixel value gradient (PVG) was defined as the slope of the resulting graph.  Results: PVG was negative for all specimens, and was found to decrease (become more negative) with bone density.  PVG demonstrated a moderate but highly significant (p < 0.001) linear correlation with bone density (R = -0.79).  Conclusion: Ultrasonic images of bone may be analyzed in ways that yield quantitative information about bone density.

• Sarah Morgenson  --  "Using NMR Technology to effectively determine Soil Water Content"
  Abstract: Soil water measurements are important for understanding how much irrigation is needed in order to cultivate crops on a large scale. There are several methods used in order to determine soil moisture content however, the most widely used is the Neutron Probe. The probe works by sending out radioactive neutrons that collide with Hydrogen nuclei, causing the neutrons to slow down. When the signal is relayed back to the sensor allows us to estimate the amount of hydrogen in a given soil sample. Due to the invasive radioactive nature of the probe it is becoming less and less financially feasible to operate. My poster explains the extensive research we did over the summer in order to build and test the NMR probe. 

• Ying Wun Yvonne Ng (Oral too)  --  "Noise Analysis of the Prototype Gas Electron Multiplier Radiation Detector and its Long Term Behavior Study by Kpix"
  Abstract: The Gas Electron Multiplier (GEM) technology is one of the next generation radiation detector technologies that utilized the ionization in gaseous medium to detect electrically charged particles from various radiations. University of Texas at Arlington’s advanced detector group has begun its work on GEM technology since the early 2000s to develop a new high precision detector for future particle detection.
  During the course of the past few years, data has been taken continuously to characterize the 30cmx30cm prototype detector. Statistical method has been developed to study the device’s long term behavior. The effect of atmospheric pressure to the detector amplification has been compensated by a correction algorithm. Electronic noise is studied in a systematic fashion in hope to reduce the influence on the data due to aging of the electronic chip. In this talk, I will present the latest result of the long term stability study of the prototype detector and its ramification to future use.

• Khanh Nguyen  --  "Monte Carlo simuations of Crystallization in Pentomino Fluids"
  Abstract: We studied crystallization in two-dimensional fluids using a simple lattice model and Monte Carlo simulations. In this “polyomino” model, adsorbed molecules are represented by shapes on a square lattice. Our group previously studied the phase behavior of four-site “tetrominoes” (Barnes et al., Langmuir 25 (2009) 6702.) Now with the same method, we investigate selected pentominoes to study the dynamics of crystallization at high chemical potential.
  Monte Carlo simulations are stochastic simulations, in which particles are moved randomly and the new states accepted or rejected according to thermodynamic criteria. In our simulations particles can translate and rotate, and also can leave and enter the system.
  A new analysis program was written to identify the crystalline environment of each piece. A cluster counting algorithm is then used to gather crystalline pieces into clusters. The average size and number of clusters are then calculated from this data. As time increases, the average size and the maximum size of the crystals increase, while the number of crystals decreases. This is the result of some crystals shrinking and disappearing during the simulation while others increase in size. Interestingly, the average size of the crystals grows at different rates if we changed the relative frequency of insertions, deletions and translation moves.

• Anna Pittman  --  "CASSY Robots"
  Abstract: The CASSY Robot is a project involving two square robots. The goal was to code the robots to do a certain set of tasks autonomously. To begin with, our task was to code the robot so that it would roam a certain area, marked off by black tape. When the robot hit the black tape, it knew to back up and turn around. It was able to do this thanks to the light sensor that was attached to the bottom of the robot. Next, we coded the robot so that when it hit an obstacle it would stop, back up, and turn to go around the obstacle. This was primarily to prevent the robot from hurting itself if it hit an obstacle. This was accomplished by using touch sensors set up as bumpers. Once that was accomplished, we attached sonar sensors and created code so that one robot was able to find and track the other robot in an intruder/cop scenario. 

• Amanda Turbyfill  --  "Investigating Possible Departures from Maxwellian Energy Distributions in Nebulae using High-Resolution Emission-Line Spectra"
  Abstract: The derivation of ionic abundance ratios from collisionally excited emission lines in gaseous nebulae requires knowledge of the physical state of the gas, particularly the electron kinetic temperature, Te , to which the resulting abundances are highly sensitive. A long-standing problem in nebular analyses has been of pervasive discrepancies among values of Te obtained from different diagnostic ratios for a single nebula. Recently Nicholls et al. (2012, ApJ, 752, 148) have suggested that the electrons in nebulae may not obey an equilibrium Maxwell-Boltzmann (M-B) energy distribution, but instead follow a “κ distribution” seen in many solar system plasmas, a family of distributions for which the M-B distribution is the limiting case where κ -> ∞. The high-energy tail of supra-thermal electrons in kappa distributions have a disproportionate effect on quantities with strong dependences on electron energy (such as Te diagnostics) for even modest departures from M-B distributions. We apply prescriptions given by Nicholls et al. (2013, ApJS, 207, 21) to high-resolution (R=36,700) optical spectra of 10 planetary nebulae obtained with the 2d-coudé echelle spectrograph on the 2.7 m Harlan J. Smith Telescope at McDonald Observatory. The advantages of these data include their broad spectral coverage and sufficiently high spectral resolution to separate blended lines and assess possible atmospheric absorption issues. The line fluxes were obtained using ROBOSPECT, an automated spectral line measurement package developed by Waters & Hollek (2013, PASP, 125, 1164).  We solve both for Te under the assumption of M-B distributions, and the parameters of κ distributions consistent with the data. Our goal is to test whether the κ distribution hypothesis provides a better fit to the observed line ratios.  Finally, we discuss effects on the derived ionic abundances under this alternate description of the particle energy distributions. This research was supported by NSF grant AST 0708245 and the John W. Cox Endowment for Advanced Studies in Astronomy at the University of Texas at Austin.

• Irene Vargas  --  "The Variation of the Accretion Rate of Dwarf Nova SS Cyg"
  Abstract: A dwarf nova is a type of close interacting binary system in which material is transferred from one star to a white dwarf through an accretion disk. Dwarf novae release outbursts caused by a temporary enhancement in the rate of mass transfer in the accretion disk. A prominent theory, called “Hibernation”, claims that the accretion rate of a nova changes cyclically over thousands of years or longer, making it a dwarf nova and later reaching a “dormant” period before becoming a nova once more. Hibernation predicts that a dwarf novae will experience secular changes in its accretion rates over the course of millennia. We are now able to get evidence to test this prediction for the first time. We studied the light curve of the dwarf nova SS Cygni (SS Cyg) from the years 1896 to 2013. This gave us a total of 430,809 observations spanning more than a century and this gives us a chance to look for changes, by measuring the average flux level and how it is changing over the decades. We saw that the accretion rate of the dwarf nova dropped by ~30%, which is consistent with hibernation. However, we also observed that the flux did not decline steadily and that there must be some other effect which is competing with hibernation.

• Jessica Zimmerman  --  "Tectonic Tremor and Brittle Seismin Events Triggered along the Eastern Denali Fault in Northwest Canada"
  Abstract: In this study, we search for triggered tremor and brittle seismic events along the Eastern Denali Fault (EDF) in northwest Canada, an intraplate strike-slip region where tremor has not been previously observed. We retrieve seismic data for 19 distant earthquakes from 9 broadband stations monitored by the Canadian National Seismograph Network (CNSN). We apply high-pass or band-pass filters to the seismic data depending on the epicentral distance in search of local tremor sources. Triggered tremor signals exhibit high-frequency contents, have long duration (> 15 s), are coincident with passing surface waves of the distant earthquakes, and are observable among nearby stations. Using this simple approach, we have identified 4 mainshocks that triggered tremor in our study region: the 2011/03/11 Mw9.1 Tohoku, 2012/04/11 Mw8.6 Sumatra, 2012/10/28 Mw7.7 Haida Gwaii, and 2013/01/05 Mw7.5 Craige, Alaska earthquakes. Our initial locations indicate that the tremor source occurs on or near the southeastern portion of the EDF near the fault trace. In addition to our triggered tremor sources, we also identified many “brittle” events with very short durations that were triggered by the Rayleigh waves of the 2012/10/28 Mw7.7 Haida Gwaii earthquake. While we were unable to locate these events, they appear to be seismically similar to icequakes observed in Antarctica, and they occur during the dilatational strain changes caused by the Rayleigh waves.