Bulletin of the American Physical Society
2008 APS April Meeting and HEDP/HEDLA Meeting
Volume 53, Number 5
Friday–Tuesday, April 11–15, 2008; St. Louis, Missouri
Session S1: Poster Session III (2:00-5:00pm) |
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Sponsoring Units: APS Room: Hyatt Regency St. Louis Riverfront (formerly Adam's Mark Hotel), Fourth Floor Lobby |
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S1.00001: COMPUTATIONAL PHYSICS EDUCATION POSTERS |
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S1.00002: Computational Physics Education at Eastern Illinois University: Undergraduate Curriculum and Research Jie Zou We have recently developed a new B.S. in Physics: Computational Physics Option which offers a balanced curriculum in theoretical and experimental physics and an exposure to the computational approach in physics and engineering. Two new courses have been developed: ``Computational Methods in Physics and Engineering'' and ``Computational Physics''. Undergraduate research with an emphasis on computation is also an integral part of this curriculum. One research area that we have introduced to our students is the computational modeling and simulation of nanoscale materials. An example is a project that involved phonon dispersion in nanoscale heterostructures, which students obtained by solving the lattice wave equation using the Finite-Difference method. An ongoing undergraduate project involves applying Molecular Dynamics Simulation to the study of the random motion and kinetic theory of gases. In this paper, we present details on our Computational Physics curriculum and the above computational projects. We also analyze the educational benefits that the Computational Physics curriculum and research projects bring to our students. [Preview Abstract] |
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S1.00003: Coupled pressure and velocity distributions in a pressure-driven flow inside a long pipe with fluid injection through porous walls. Alexander L. Frenkel, Leonid Bolshinskiy We are studying steady flows of Newtonian liquids in pipes with porous walls. One end of the pipe is closed; the ambient liquid is injected through the pipe wall under the Darcy-Weisbach law and exits at the open end with a pressure that is kept below the uniform fluid pressure outside the pipe walls. The inside pressure varies with the axial coordinate and is coupled with the varying axial velocity averaged over the cross-section of the pipe. For a long pipe, the Karman-Polhausen averaging of Navier-Stokes equations is used for both laminar and turbulent flow regimes. We obtain a boundary value problem for a nonlinear second-order differential equation governing the velocity distribution and explore numerous flow regimes by numerically solving it. Hence, the pipe pressure is found as a quadratic expression in terms of the velocity derivative. At sufficiently high Reynolds numbers, quite unlike the standard pipe flow with uniform velocity, even the turbulent friction turns out negligible in comparison with the pressure gradient required for accelerating the liquid toward the exit. The inertial approximation allows for an analytic solution. The nonzero-gravity generalization is obtained, and applications to channels with fine-mesh screen walls utilized for the delivery of liquid propellant to the engine at low gravity, are discussed. [Preview Abstract] |
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S1.00004: Band structure of photons in layered DPS/DNG materials Joseph Shahbazian, Aram Karakashian In this project the main goal is to study the band gaps of a one dimensional photonic crystal composed of alternating layers of DNG and DPS materials. The material's optical parameters (electric permittivity and magnetic permeability) are complex and frequency dependent to account for both dispersion and absorption. Here we present the non-Bragg band gaps in a one dimensional photonic crystal composed of alternating layers of DNG and DPS materials. Our center of attention is the study of the zero permittivity, zero permeability and zero average refractive index gaps and the transmission and reflection of photons. [Preview Abstract] |
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S1.00005: The time-dependent, electromagnetic Aharonov-Bohm effect Zachary Kertzman, Athanasios Petridis Numerical, time-dependent solutions to the relativistic Dirac equation coupled with an external electromagnetic field are obtained using the staggered leap-frog method on a spatial lattice in two dimentions. The numerical stability of the method is evaluated and ensured by appropriate choices of the lattice constant and the time step. The action of the magnetic or electrostatic potentials in the region of zero electromagnetic fields is evaluated by means of the produced diffraction patterns. The time-dependent intereference as the spinor is guided around a quantum ring centered about an infinitely-long solenoid magnet is also studied. [Preview Abstract] |
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S1.00006: Entanglement of Atoms with Vacuum in Jaynes Cummings Model Samina Masood, Allen Miller We investigate the conditions for entanglement in a system of two atoms and two photon modes with a vacuum, using the Jaynes-Cummings model in the rotating-wave approximation. The results of previous studies are generalized to the case of non-resonant conditions. It is found that the strength of entanglement in atoms is a periodic function of time, in general. We explicitly show that our results are in agreement with existing results and reproduce the existing entanglement conditions under appropriate limits. [Preview Abstract] |
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S1.00007: Glucose and Aging John T.A. Ely When a human's enzymes attach glucose to proteins they do so at specific sites on a specific molecule for a specific purpose that also can include ascorbic acid (AA) at a high level such as 1 gram per hour during exposure. In an AA synthesizing animal the manifold increase of AA produced in response to illness is automatic. In contrast, the human non-enzymatic process adds glucose haphazardly to any number of sites along available peptide chains. As Cerami clarified decades ago, extensive crosslinking of proteins contributes to loss of elasticity in aging tissues. Ascorbic acid reduces the random non-enyzmatic glycation of proteins. Moreover, AA is a cofactor for hydroxylase enzymes that are necessary for the production and replacement of collagen and other structural proteins. We will discuss the relevance of ``aging is scurvy'' to the biochemistry of human aging. [Preview Abstract] |
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S1.00008: ASTROPHYSICS POSTERS |
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S1.00009: The Laws of Parallelism, Convergence and Divergence Applied to Some Astrophysical Phenomena Stewart Brekke The gravitational accelerations of various heavenly bodies can illustrate the concept of parallelism by plotting them over time forming straight lines. $g(earth)= 9.8 m/s^2$, $g(moon) = 1.6m/s^2$ and $g(mars)= 3.4m/s^2$. The distance between the lines g(earth) and g(mars) is $6.4m/s^2$ and the distance between the lines g(earth) and g(moon) is $8.2m/s^2$. Thus, the greater parallelism (similarity) is between g(earth) and g(mars) since the distance between the lines is smaller than between g(earth) and g(moon). The Law of Convergence states that the smaller the angle between two curves, the greater the convergence. The Law of Divergence states that the greater the angle between two curves, the greater the divergence. In the evolution of post mainsequence stars the evolutionary Hayashi track makes and angle of about 115 for a 1M star, about 132 for a 5M star and for a 10M star 120. Therefore, the divergence of a 5M star is greater than for a 5M or 10M star or breater disimilarity from the main sequence track kstars. The angles of convergence of Hayashi tracks for stars approaching the main sequence is about 155 for a 4M, 160 for a 2M or 56 for a 0.1M star indicating that the Hayashi track for a 0.1M star is more similar to the main sequence stars. In nucleosynthesis of elements the angle of divergence is approx. 11.35 degrees between the curve for light nuclei and heavier nuclei in the proton-neutron curves. In this manner convrgence, divergence and parallelism can be quantified for phenomena. [Preview Abstract] |
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S1.00010: Pioneer Anomaly: Artifact or Real Astrophysical Phenomenon of the Solar System. Jacques Leibovitz A crucial experiment is suggested to determine conclusively whether the Pioneer anomaly (PA) is an artifact or a real astrophysical phenomenon of the Solar System (APSS). NASA may already have in its archives the data needed. An experimental proof that the PA is an artifact would end speculations on possible new physics to explain the PA. If the experiment proves that the PA is an APSS, then a second crucial experiment is suggested to determine conclusively whether the (then proven) APSS is, or is not, produced by dark matter (DM). NASA may already have in its archives the data needed. If the answer is: ``Not DM,'' then physicists would search for a suitable new physics to explain the PA. However, if the answer is DM, then it would be necessary to reconcile the amount of DM, needed in the Solar System to explain the PA, with the ranging results used by NASA to fix the locations of the planets. That might require a new physics, but in a different direction. Either way would improve our understanding of our Solar System. [Preview Abstract] |
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S1.00011: Multi-Angle Multi-Group Radiation-Hydrodynamics Simulations Of Core-Collapse Supernovae Christian D. Ott, Adam Burrows, Luc Dessart, Eli Livne, Jeremiah Murphy We present new results from axisymmetric multi-angle, multi-group neutrino radiation-hydrodynamic calculations of the postbounce phase of rotating and nonrotating core-collapse supernovae. We analyze the effect of the multi-angle treatment on neutrino radiation field anisotropies and the net energy deposition and compare our results in detail with multi-group flux-limited diffusion counterpart calculations. [Preview Abstract] |
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S1.00012: Cylindrical Harmonic Galaxy Classification Jeff Riess, Mickey Kutzner In this study, we investigate the use of features in the Spherical Harmonic power spectra to aid in the classification of galaxies. Let $I(r,\theta)$ represent a galaxy image function in polar coordinates. The image function may be represented as a two-dimensional Fourier-Bessel series. The coefficients in the expansion, $A_{n,i}$ and $B_{n,i}$, multiply the radial Bessel functions of order n, $J_{n}(\alpha_{n,i}r/R)$ and the polar functions $cos(n\theta)$ and $sin(n\theta)$, respectively. The coefficients are known as the Fourier-Bessel Transform (FBT) of $I(r,\theta)$. The parameter $\alpha_{n,i}$ is the ith root of the Bessel function of the first kind of order $n$, $J_{n}(x)$, and R is the radius to the edge of the galaxy image. We have computed the coefficients $A_{n,i}$ and $B_{n,i}$ for a number of representative FBT spectra. Spectra are presented as 3D plots of the modulus of $A_{n,i}$ and $B_{n,i}$ versus the root number, $i$, and the order $n$. Radial structures (such as spiral arms) are manifested in the spectra as peaks in amplitude at certain values of $i$, whereas, azimuthal variations are seen as amplitude peaks at particular values of $n$. Since each galaxy type will have a unique spectrum type due to its distinct matter distributions, we investigate the possibility of automatically classifying galaxies by minimizing the Euclidean distance of the galaxy's FBT spectrum to typical spectra of each morphological type. [Preview Abstract] |
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S1.00013: Distinguishing Modified Gravity from Dark Energy Phillip Zukin, Edmund Bertschinger The acceleration of the universe can be explained either through dark energy or through the modification of gravity on large scales. In this paper we investigate modified gravity models and compare their observable predictions with dark energy models. Modifications of general relativity are expected to be scale-independent on super-horizon scales and scale-dependent on sub-horizon scales. For scale-independent modifications, utilizing the conservation of the curvature scalar and a parameterized post-Newtonian formulation of cosmological perturbations, we derive results for large scale structure growth, weak gravitational lensing, and cosmic microwave background anisotropy. For scale-dependent modifications, inspired by recent $f(R)$ theories we introduce a parameterization for the gravitational coupling $G$ and the post-Newtonian parameter $\gamma$. These parameterizations provide a convenient formalism for testing general relativity. However, we find that if dark energy is generalized to include both entropy and shear stress perturbations, and the dynamics of dark energy is unknown a priori, then modified gravity cannot in general be distinguished from dark energy using cosmological linear perturbations. [Preview Abstract] |
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S1.00014: The Advanced Gamma-ray Imaging System (AGIS): A Nanosecond Time Scale Stereoscopic Array Trigger System. Frank Krennrich, J. Buckley, K. Byrum, J. Dawson, G. Drake, D. Horan, H. Krawzcynski, M. Schroedter Imaging atmospheric Cherenkov telescope arrays (VERITAS, HESS) have shown unprecedented background suppression capabilities for reducing cosmic-ray induced air showers, muons and night sky background fluctuations. Next-generation arrays with on the order of 100 telescopes offer larger collection areas, provide the possibility to see the air shower from more view points on the ground, have the potential to improve the sensitivity and give additional background suppression. Here we discuss the design of a fast array trigger system that has the potential to perform a real time image analysis allowing substantially improved background rate suppression at the trigger level. [Preview Abstract] |
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S1.00015: The Advanced Gamma-ray Imaging System (AGIS): Telescope Optical System Designs Vladimir Vassiliev, Jim Buckley, Abe Falcone, Steven Fegan, John Finley, Victor Gaurino, David Hanna, Philip Kaaret, Alex Konopelko, Henric Krawczynski, Roger Romani, Trevor Weekes AGIS is a conceptual design for a future ground-based gamma-ray observatory based on an array of $\sim$100 imaging atmospheric Cherenkov telescopes (IACTs) with a sensitivity to gamma-rays in the energy range 40 GeV-100 TeV. The anticipated improvement of AGIS sensitivity, angular resolution, and reliability of operation imposes demanding technological and cost requirements on the design of the IACTs. In this submission we focus on the optical system (OS) of the AGIS telescopes and consider options which include traditional Davies-Cotton and the other prime- focus telescope designs, as well as a novel two-mirror aplanatic OS originally proposed by Schwarzschild. Emerging new mirror production technologies based on replication processes such as cold and hot glass slumping, cured CFRP, and electroforming provide new opportunities for cost effective solutions for the design of the OS. We evaluate the capabilities of these mirror fabrication methods for the AGIS project. [Preview Abstract] |
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S1.00016: The Advanced Gamma-ray Imageing System (AGIS): Simulation Design Studies V. Bugaev, J. Buckley, S. Digel, S. Fegan, S. Funk, A. Konopelko, H. Krawczynski, S. LeBohec, G. Maier, V. Vassiliev We present design studies for AGIS, a proposed array of $\sim$100 imaging atmospheric Cherenkov telescopes for gamma-rays astronomy in the 40GeV to 100 TeV energy regime. We describe optimization studies for the array configuration, pixel size and field of view aimed at achieving the best sensitivity over the entire energy range and best angular resolution for a fixed project total cost. [Preview Abstract] |
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S1.00017: The Advanced Gamma-ray Imaging System (AGIS): Telescope Mechanical Designs V. Guarino, J. Buckley, K. Byrum, A. Falcone, S. Fegan, J. Finley, D. Hanna, D. Horan, P. Kaaret, A. Konopelko, H. Krawczynski, F. Krennrich, R. Wagner, M. Woods, V. Vassiliev The concept of a future ground-based gamma-ray observatory, AGIS, in the energy range 40 GeV-100 TeV is based on an array of {\$}$\backslash $sim {\$}100 imaging atmospheric Cherenkov telescopes (IACTs). The anticipated improvements of AGIS sensitivity, angular resolution and reliability of operation impose demanding technological and cost requirements on the design of IACTs. The relatively inexpensive Davies-Cotton telescope design has been used in ground-based gamma-ray astronomy for almost fifty years and is an excellent option. We are also exploring alternative designs and in this submission we focus on the recent mechanical design of a two-mirror telescope with a Schwarzschild-Couder (SC) optical system. The mechanical structure provides support points for mirrors and camera. The design was driven by the requirement of minimizing the deflections of the mirror support structures. The structure is also designed to be able to slew in elevation and azimuth at 10 degrees/sec. [Preview Abstract] |
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S1.00018: The Advanced Gamma-ray Imaging System (AGIS): Camera Electronics Designs H. Tajima, J. Buckley, K. Byrum, G. Drake, A. Falcone, S. Funk, J. Holder, D. Horan, H. Krawczynski, R. Ong, S. Swordy, R. Wagner, D. Williams AGIS, a next generation of atmospheric Cherenkov telescope arrays, aims to achieve a sensitivity level of a milliCrab for gamma-ray observations in the energy band of 40 GeV to 100 TeV. Such improvement requires cost reduction of individual components with high reliability in order to equip the order of 100 telescopes necessary to achieve the sensitivity goal. We are exploring several design concepts to reduce the cost of camera electronics while improving their performance. These design concepts include systems based on multi-channel waveform sampling ASIC optimized for AGIS, a system based on IIT (image intensifier tube) for large channel (order of 1 million channels) readout as well as a multiplexed FADC system based on the current VERITAS readout design. Here we present trade-off in the studies of these design concepts. [Preview Abstract] |
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S1.00019: Quasar Additional Intrinsic Redshift Mechanism?? C.F. Gallo From observations and spectral peculiarities, Quasars have complex ``intrinsic'' redshift(s) added to Hubble redshift. Different Quasars have variable surrounding cloud of plasma and gases (atomic and molecular). Variable local redshifting ensues from photon energy-loss interactions with surrounding cloud. Two Quasar anomalies are examined. (1) The H:21cm redshift is small compared to larger redshift of higher energy photons, possibly due to Raman redshift since low energy H:21cm photons have INsufficient energy to excite redshifting Raman levels. (2) The hydrogen Balmer lines show an additionally redshifted ($\sim$1000km/s) broadened component, possibly due to Raman hyperfine redshift via hydrogen nuclear spin. This extra H:Balmer-type component is NOT present in CIV and MgII lines which have NO nuclear spin. NOTE: Any Raman energy-loss mechanism will effectively redshift the original line, but effectiveness will decrease as line progressively redshifts away from initial value, becoming ineffective with saturated redshift value. This ensues since photon Raman cross-section decreases as initial line redshifts off resonance, with cross- section eventually becoming negligible, consistent with Quasar data. [Preview Abstract] |
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S1.00020: Observation of the High-Energy Peaked BL Lac Object 1ES 1218+304 with STACEE Naureen Akhter, J. Ball, J.E. Carson, C.E. Covault, D.D. Driscoll, P. Fortin, D.M. Gingrich, D.S. Hanna, A. Jarvis, J. Kildea, T. Lindner, C. Mueller, R. Mukherjee, R.A. Ong, K. Ragan, D.A. Williams, J. Zweerink We present the analysis of recent high-energy gamma-ray observations of the BL Lac object 1ES 1218+304 with the Solar Tower Atmospheric Cherenkov Effect Experiment (STACEE). 1ES 1218+304 is an X-ray bright high-energy peaked BL Lac (HBL) that is also a source of TeV gamma rays, and has recently been detected by the atmospheric Cherenkov telescopes MAGIC and VERITAS. We will present results from STACEE observations of 1ES 1218+304 in the 2006 and 2007 observing seasons. [Preview Abstract] |
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S1.00021: Thermo$-$Rotational Instability in Plasma Disks Around Compact Objects$*$ Bruno Coppi Differentially rotating plasma disks, around compact objects, that are imbedded in a ``seed'' magnetic field are shown to develop vertically localized ballooning modes that are driven by the combined radial gradient of the rotation frequency and the vertical gradients of the plasma density and temperature [1]. When the electron mean free path is shorter than the disk height and the (vertical) thermal conductivity can be neglected, the vertical particle flows produced by of these modes have the effect to drive the density and temperature profiles toward the ``adiabatic condition'' where $\eta_{T}\equiv(d{ln}T/dz/(d{ln}n/dz)=2/3$. Here $T$ is the plasma temperature and $n$ the particle density. The faster growth rates correspond to steeper temperature profiles $(\eta_ {T}>2/3)$ such as those produced by an internal (e.g. viscous) heating process. In the end, ballooning modes excited for various values of $\eta_{T}$ can lead to the evolution of the disk into a different current carrying configuration such as a sequence of plasma rings[2].\\ $*$Sponsored in part by the U.S. Department of Energy\\ {[1]}B. Coppi, M.I.T. (LNS) Report HEP, 07/02, Cambridge, MA (2007), \textit{Invited Paper at the International Symposium on ``Momentum Transport in Jets, Disks and Laboratory Plasmas'', Alba, Piedmont, September 2007}, to be published in Europhysical Letters (EPL, IOP)\\ {[2]}B. Coppi andF. Rousseau, \textit{Ap. J.}, \textbf{641}, 458, (2006) [Preview Abstract] |
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S1.00022: A High Frequency Search for Gravitational Wave Bursts Brennan Hughey We present a first look at an all-sky gravitational wave burst search in the frequency range 1 to 6.5 kHz using LIGO data. Previous burst searches with ground-based interferometers have been limited to frequencies below 2 kHz. However, various models predict gravitational wave emission in the several kiloHertz range from astrophysical phenomena including gravitational collapse, neutron star modes and low mass black hole mergers. This shot-noise dominated frequency regime can be analyzed with the same tools as lower frequency analyses. [Preview Abstract] |
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S1.00023: Reheating of the universe after inflation with f(phi)R gravity Yuki Watanabe, Eiichiro Komatsu We show that reheating of the universe occurs spontaneously in a broad class of inflation models with $f(\phi)R$ gravity ($\phi$ is inflaton). The model does not require explicit couplings between $\phi$ and bosonic or fermionic matter fields. The couplings arise spontaneously when $\phi$ settles in the vacuum expectation value (vev) and oscillates, with coupling constants given by derivatives of $f(\phi)$ at the vev and the mass of resulting bosonic or fermionic fields. This mechanism allows inflaton quanta to decay into any fields which are not conformally invariant in $f(\phi)R$ gravity theories. [Preview Abstract] |
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S1.00024: Projectile acceleration to a velocity over the Earth's escape velocity and application in planetary science. T. Kadono, K. Shigemori, S. Fujioka, K. Otani, T. Sano, A. Shiroshita, Y. Hironaka, Y. Sakawa, N. Ozaki, T. Kimura, K. Miyanishi, T. Endo, M. Arakawa, A. Nakamura, S. Sugita, T. Matsui Impact velocity of meteorites on Earth at the final stage of planetary accretion becomes more than 10 km/s. However, macroscopic (larger than 0.1 mm) projectiles are not easily accelerated to more than 10 km/s by two-stage light-gas guns. One possible method to a velocity larger than 10 km/s is the irradiation of high-intensity lasers. Here, we describe the first results of projectile (glass spheres) acceleration experiments to a velocity higher than 10 km/s using GEKKO XII laser at Institute of Laser Engineering. Glass spheres are accelerated to a velocity of 15 km/s. This is enough to simulate hypervelocity impacts on the surface of the proto-planets and investigate various phenomena caused by the impacts such as impact vaporization of silicate rocks, crater formation on rocks, and metamorphism due to high pressure. [Preview Abstract] |
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S1.00025: Limits on Relativistic Magnetic Monopole Flux from RICE Daniel Hogan The Radio Ice Cherenkov Experiment (RICE) is a radio antenna array at the South Pole. A Monte Carlo simulation of magnetic monopole propagation through polar ice is used to determine RICE's cross-section for monopole detection. We present final results for ultrarelativistic ($\gamma\geq10^7$) magnetic monopole flux upper bounds based on RICE observations from 2001 through 2005. This limit is the strongest direct measurement of ultrarelativistic monopole flux. [Preview Abstract] |
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S1.00026: The Advanced Gamma-ray Imaging System (AGIS): Focal Plane Detectors Reshmi Mukherjee, K. Byrum, G. Drake, A. Falcone, S. Funk, D. Horan, H. Tajima, B. Wagner, D. Williams Report of the Focal Plane Instrumentation Working Group, AGIS collaboration: The Advanced Gamma-ray Imaging System (AGIS) is a concept for the next generation instrument in ground-based very high energy gamma-ray astronomy. It has the goal of achieving significant improvement in sensitivity over current experiments. One of the main requirements for AGIS will be to achieve higher angular resolution than current imaging atmospheric Cherenkov telescopes (IACTs). Simulations show that a substantial improvement in angular resolution may be achieved if the pixel size is reduced to 0.05 deg, below that of current IACTs. Reducing the cost per channel and improving reliability and modularity are other important considerations. Here we present several alternatives being considered for AGIS, including both silicon photomultipliers (SiPMs) and multi-anode photomultipliers (MAPMTs) and summarize results from feasibility testing by various AGIS photodetector group members. [Preview Abstract] |
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S1.00027: CZT Detector Development for Hard X-ray Astronomy A.B. Garson III, Q. Li, M. Beilicke, R. Bose, A. Burger, P. Dowkonnt, M. Groza, G. Simburger, H. Krawczynski Cadmium Zinc Telluride (CZT) has proven itself as an excellent material for detection of hard X-rays. Advances in crystal growth have increased the quality and size of available single CZT crystals. We report on our ongoing development and characterization of CZT detector systems. With our dedicated class-100 cleanroom, we fabricate detectors using CZT crystals from different manufactures. Using photolithography and e-beam evaporation, we can produce detectors with different contact designs (pixellated, strip, monolithic, steering grid), contact dimensions (down to 50 microns), and contact materials (In, Ti, Au, etc.) . In addition, we develop ASIC readouts for various CZT detector applications, including our characterization of the detectors. We measure I-V and C-V curves for the detectors as well as their spectroscopic performance. We compare measured results with those from detailed modelling and simulations. The CZT detector systems can then be optimized for applications such as X-ray imaging and polarimetry with satellite or balloon-borne instruments. [Preview Abstract] |
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S1.00028: Eight and a half minutes. Gabriele Varieschi An interesting conceptual question, regarding the actual position of the Sun at sunset or sunrise, is analyzed and discussed in terms of fixed vs. rotating frames of reference. A simple, educational experiment can be easily set up to demonstrate this effect and introduce topics such as rotating systems, apparent motion and the Coriolis effect. [Preview Abstract] |
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S1.00029: Searching for gravitational wave fingerprints of SGR QPOs Rubab Khan Soft Gamma Repeaters are young neutron stars or supernova remnants with very strong magnetic fields that irregularly emit X-ray and gamma-ray bursts, and occasionally produce huge burst flares. Quasi periodic oscillations (QPOs) in the X-ray tail of such flares have been observed during the August 1998 giant flare from SGR 1900+14 and the Dec 2004 giant flare from SGR 1806-20. These QPOs can plausibly be accompanied by gravitational wave emission up to the energy scale of the electromagnetic emission. The search algorithm used for the analysis relies on coincident data streams from multiple interferometric gravitational wave detectors and incorporates the temporal and directional information available from detected SGR flares. [Preview Abstract] |
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S1.00030: ABSTRACT WITHDRAWN |
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S1.00031: Active seismic isolation systems for Enhanced and Advanced LIGO Jeffrey Kissel In order to mitigate the dominant low-frequency noise source for the next generation of interferometric gravitational wave detectors, several new systems are in development that will actively isolate optics and readout sensors from ground motion. For enhanced LIGO the output mode cleaner and photodiode readouts are to be positioned on a singe-stage active isolation platform which will reduce ground motion by at least a factor of 50 at 1 Hz. Advanced LIGO will include several single-stage isolation platforms and the core optics will be suspended from two-stage platforms which will suppress ground motion by a factor of 3000 at 10 Hz. We present first results from the single-stage isolation platforms now installed at the observatories and comparisons between expected and observed isolation performance. [Preview Abstract] |
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S1.00032: ACCELERATORS AND STORAGE RINGS POSTERS |
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S1.00033: Computation of Transfer Maps from Surface Data with Applications to ILC Damping Ring Wigglers Chad Mitchell, Alex Dragt Nonlinear wiggler effects are important for determining the dynamic aperture of electron/positron damping and storage rings. Wiggler transfer maps in general depend sensitively on nonlinear fringe-field and high-order-multipole effects. The inclusion of these effects requires a detailed and realistic model of the interior and fringe magnetic fields, including knowledge of high spatial derivatives. A collection of surface fitting methods have been developed for extracting this information directly from 3-dimensional magnetic field data on a grid, as provided by various 3-dimensional finite element field codes. The virtue of surface methods is that they exactly satisfy the Maxwell equations and are relatively insensitive to numerical noise in the data. These techniques are used to compute, in Lie-algebraic form, realistic transfer maps for the proposed ILC Damping Ring wigglers. The resulting transfer maps are then used to determine the effect of the proposed wigglers on the dynamic aperture of the ILC Damping Rings. [Preview Abstract] |
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S1.00034: Multi-bunch Plasma Wakefield Accelerator Experiments at the BNL ATF Patric Muggli, Themos Kallos, Tom Katsouleas, Vitaly Yakimenko, Marcus Babzien, Karl Kusche, Igor Pogorelsky, Wayne Kimura We present initial results obtained with a plasma wakefield accelerator driven by a train of microbunches. The microbunch train is produced with a masking technique [P. Muggli et al., this conference]. The plasma is produced in a cm-long gas-filled capillary discharge. The plasma density is measured using Stark broadening of the hydrogen H-alpha line. It is adjusted such that the plasma wavelength is equal to the microbunches spacing. In this case the train resonantly drives the wake, and the accelerating field behind the train with a variable number of microbunches is maximized. The energy loss of each microbunch increases with the microbunch number and depends on the charge in each microbunch. The accelerating wake field is sampled by a witness bunch following the drive train. This multi-bunch method could be used to multiply the energy of a future linear particle collider with a high efficiency. The experimental set-up, as well as detailed experimental results will be presented. [Preview Abstract] |
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S1.00035: Fast Ion Generation by Short High Intensity Laser Pulses Galina Dudnikova, Valery Bychenkov Developments in laser technology have enabled high power lasers to produce multi-terawatt picoseconds and femtosecond pulses which allow to examine the fundamental physics of high intensity, $I$~$>$10$^{19}$~W/cm$^{2}$, laser-produced plasmas and have many potential applications: compact neutron source,~new methods in nuclear medicine, isotope and relativistic ion beam production. On the base of 2D PIC simulation ion generation from an overdense plasma foil illuminated by the laser pulse with variable intensity and FWHM duration has been studied. Formation of quasi-monoenergetic ion beam takes place with thin homogeneous foils with light and heavy ions. The conditions of optimal ion acceleration in terms of the intensity and pulse duration are carried out. [Preview Abstract] |
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S1.00036: MaRIE: Matter-Radiation Interactions in Extremes, a Signature Facility Providing Experimental Resources for Transformational Materials Discovery Cris W. Barnes, R.D. Fulton, David J. Funk, Carter P. Munson, John L. Sarrao, Kurt F. Schoenberg Materials-centric national security science is vital for addressing 21st Century missions of energy security, stockpile stewardship, homeland security, and providing discovery science. Relevant grand challenges of the next two decades include: closing the 10~TW gap between the energy we have and the energy we need; transforming the enterprise of the nuclear weapons complex; and detecting threats with unprecedented sensitivity and efficiency. MaRIE is a proposed signature facility for Los Alamos National Laboratory that is centered on creating and exploiting radiation-matter interactions and providing transformational materials performance through validated predictive multi-scale understanding. Building on the capabilities of the Los Alamos Neutron Science Center, components of MaRIE will provide extreme irradiation fluxes, multiple diagnostic probes to bridge the ``micron gap'' between atomic scale/molecular dynamics and continuum model/integrated tests, and synthesis and characterization labs to make, measure, and model materials. This presentation will describe the challenges, approaches, and implementation timescale being developed for MaRIE, and engender input and interest by the scientific user community. [Preview Abstract] |
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S1.00037: GRAVITATION POSTERS |
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S1.00038: A new torsion balance for direct tests of the Universality of Free Fall. Kasey Wagoner, Amit Sircar, Ramanath Cowsik The principle of equivalence between passive gravitational and inertial mass is a corner stone of General Relativity(GR) and thus is of great interest to anyone wishing compare GR to alternative gravitational theories. We present a new instrument, in the form of a highly sensitive torsion balance, for a direct test of this equivalence. The balance which has a natural frequency of $\nu_0\sim 1.6\times 10^{-4}$Hz is viewed by an autocollimating optical lever with large dynamic range and high resolution. Based on the design of this balance we should be able to probe the universality of free fall more sensitively then the earlier experiments with about one year of data acquisition. Design and construction of all of the pieces comprising the balance are finished and final assembly is in progress. In addition to design aspects we report on the progress towards a complete instrument. [Preview Abstract] |
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S1.00039: High Resolution Black Hole Simulations Paul Walter, Richard Matzner, Jon Allen, Andrea Nerozzi, Matt Anderson Developed at the University of Texas, openGR is an open framework for numerical simulations. We discuss results of high resolution binary black hole merger simulations and the resulting gravitational radiation. Fixed Mesh Refinement (FMR) simulations using openGR were carried out on Ranger, the new supercomputer at TACC (Texas Advanced Computing Center). Convergence results are also discussed. [Preview Abstract] |
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S1.00040: Black hole motion as a quantum object or as a classical object Caroline Herzenberg Results of a recent study of transition between quantum and classical behavior are now applied to black holes. The study, based on modification of quantum behavior in a cosmological context, predicts the existence of an uncertainty in spatial position dependent upon the mass of an object, and leads to a criterion separating quantum from classical behavior. Specifying that such an uncertainty in position be smaller than the size of the object defines a critical size that appears to provide a fundamental limit distinguishing the realm of objects governed by classical laws from those governed by quantum mechanics. A new application of this criterion to black holes indicates that the motion of small black holes would be characteristically quantum mechanical, while the motion of large black holes would be classical, with the threshold distinguishing these behaviors at a Schwartzschild radius of roughly the size of a nucleon. [Preview Abstract] |
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S1.00041: Exact Solution for a Gravitational Wave Detector Dmitri Rabounski, Larissa Borissova The experimental statement on gravitational waves proceeds from the equation for deviating geodesic lines and the equation for deviating non-geodesics. Weber's result was not based upon an exact solution to the equations, but on an approximate analysis of what could be expected: he expected that a plane weak wave of the space metric may displace two resting particles with respect to each other. In this work, exact solutions are presented for the deviation equation of both free and spring-connected particles. The solutions show that a gravitational wave may displace particles in a two-particle system only if they are in motion with respect to each other or the local space (there is no effect if they are at rest). Thus, gravitational waves produce a parametric effect on a two-particle system. According to the solutions, an altered detector construction can be proposed such that it might interact with gravitational waves: 1) a horizontally suspended cylindrical pig, whose butt-ends have basic relative oscillations induced by a laboratory source; 2) a free-mass detector where suspended mirrors have laboratory induced basic oscillations relative to each other. [Preview Abstract] |
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S1.00042: The RIDGE pipeline as a method to search for gravitational waves associated with magnetar bursts Jason Lee, Shantanu Desai, Kazuhiro Hayama, Soumya Mohanty, Malik Rakhmanov, Tiffany Summerscales RIDGE is a data analysis pipleline which implements a regularized, coherent approach to search for short-duration gravitational wave signals in the data from a network of gravitational wave detectors. We discuss the RIDGE pipeline and describe its potential in the search for gravitational waves associated with soft gamma repeaters (SGRs) and anomalous X-ray pulsars (AXPs). SGRs and AXPs are thought to be the result of seismic events in the crust of a magnetar (a neutron star with a strong magnetic field) which should produce short bursts of gravitational waves. [Preview Abstract] |
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S1.00043: The Cavenish Experiment, General Relativity, Nuclear Quantum Gravitation Ronald R. Kotas The Cavendish Experiment - Demonstration clearly shows the Gravitational attraction between two masses, which is a force proportional to the Newtonian mechanics. General Relativity fails the Cavendish Experiment because there is no force between two gravitating masses but instead pictures a fallacious time-space concept. GR has no definitive proofs. The very hot corona and not GR cause the bending of light near and about the Sun The Perihelion of Mercury, the 43 arc seconds is 3.8 x 10$^{-12}$ of the total and is not a proof of GR. This Perihelion rotation is nothing more than another mode of Newtonian mechanics explained by Newtonian mechanics. Each orbit is an ellipse, a Newtonian function that adds together because of Newtonian functions and accounts for any movement and advancement of Mercury. Because of gravity and speed changes, clocks change, time does not change. Other proofs are not valid because they are Quantum effects or plainly Newtonian refractions. Nuclear Quantum Gravitation clearly explains the gravitational force between two gravitating masses because of alternating electromagnetic functions in nuclei of matter. Some 20 proofs and indications prove this, plainly and clearly. Any gravity theory that does not conform to the Cavendish demonstration is not a viable theory of gravity. With Nuclear Quantum Gravitation, the Forces are plainly and coherently unified. [Preview Abstract] |
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S1.00044: Einstein's Math Errors Profoundly Affect Mathematical and Physical Theory David Pressler Einstein treats time as a vector, however, time has no direction associated with it; it is a scalar, it only has magnitude and is specified completely by giving it a number or units. Vectors possess both magnitude and direction. To mathematically equate time with direction is ambiguous and commits a Fallacy of Ambiguity. It is physically impossible to have space with more than three directions. Any theory where time is represented as a forth direction does not represent reality, i.e., (x, y, z, t). Einstein defines the speed of light as a constant, in the equation c = d (distance)/t (time). In this direct proportion Einstein changes the time factor (denominator), when time slows down due to motion but he does not change the distance factor (numerator). This is an error. In reality, time slows down when space contracts in all three directions, in the system of Cartesian coordinates (x, y, z,); or C-Space. Pressler's Law of C-Space: The speed of light will always be measured as a constant, c, in all three directions, in ones own inertial reference frame and the speed of light will always be measured to be different in all other inertial reference frames which are at a different gravity or kinetic energy level. Time is exactly defined as the rate of physical process; how fast things take place. This new paradigm shift redefines the Michelson-Morley where both mirrors move inward toward the center of the interferometer. [Preview Abstract] |
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S1.00045: UNDERGRADUATE RESEARCH POSTERS |
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S1.00046: Limits on Expansion of Local Planetary Nebula using CCD Imaging Robert Arn, Casey Watson, Daniel Miller Over the past decade, the growing availability of CCD (Charged Couple Device) chips has provided opportunities for smaller observatories that previously existed only for the world's largest astronomical facilities. By using two SBIG CCD cameras, the ST-7 and STL-1001E, we were able to successfully image several, local planetary nebulae. Based on the data we collected and a simple model for the radiation pressure driven growth of the nebulae, we were able to place limits on their ages, mass-loss rates, and outflow velocities that are in excellent agreement with previous findings. [Preview Abstract] |
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S1.00047: Quantification of atmospheric seeing conditions while conducting observations in Ursa Major. Joshua Clifford, Brittany Jackson, Adam Jones Researchers from Telescopes in Education and Research at Murray State (TERMS) recently developed indices to quantify astronomical seeing conditions. The required images were converted from a consumer grade VHS-C camcorder video by USB powered TV tuner into an uncompressed AVI format and imported into Image J for analysis. The first analysis was for HIP 26241, also known as Iota Orionis. We reproduce the technique for a different region of the sky around HIP 65378, also known as Mizar, at a different time of year from the same urban environment. For the star in question, we determine the photometric index and measure the horizontal and vertical drift from frame to frame of the uncompressed AVI file to quantify the ``jitter'' observed in the video. Our results and the previous results for Iota Orionis with regard to photometric index and ``jitter'' will be compared. [Preview Abstract] |
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S1.00048: Resolving the Higgs Doug Schaefer At CDF, one of the main search strategies for the Higgs boson uses the WH production mode. ~ In this channel, the W boson decays into a lepton (either electron or muon) and neutrino while the Higgs boson (H) decays into a bottom quark and an anti-bottom quark pair.~ The charged leptons can be accurately detected and measured, while the neutrino and the quarks are measured relatively poorly.~ This analysis attempts to estimate the neutrino transverse energy, and then use this information to in turn correct the measurement of the quark energies.~ This method may allow a much more accurate determination of the Higgs boson mass in WH events.~ We present expected improvements in Higgs mass resolution. [Preview Abstract] |
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S1.00049: Understanding Charged Particle Backgrounds for GLAST Lindsey Perry Gamma Ray Bursts (GRBs), are the brightest events in our universe and last anywhere between milliseconds to a few minutes. GRBs are thought to occur when a giant star collapses into a black hole, or when two neutron stars collide. The Gamma-Ray Large Area Space Telescope (GLAST) is a satellite mission which will detect gamma ray photons which come from GRBs as well as other astrophysical phenommena. Although GLAST is designed to detect gamma rays, approximately 90 percent of the events which are downlinked are background events such as protons, electrons, and positrons. A major limitation of GLAST is the limited alloted downlink bandwidth, and so understanding these backgrounds may allow us to improve both the background rejection and gamma-ray purity of the resulting data. This analysis describes a technique for identifying backgrounds in the GLAST data sample, based on Artificial Neural Networks. Understanding the particle composition will help in the identification of true Gamma-rays, therefore impacting all science done with GLAST. GLAST is managed by NASA in partnership with the Department of Energy, and is scheduled to launch in early 2008. [Preview Abstract] |
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S1.00050: Improving Campus Security with Increased Lighting Efficiency while Simultaneously Reducing Light Pollution Andrew Schenk, Dan Miller, Eric Martell Many outdoor lighting fixtures fail to enhance the security of the assets they were designed to protect; moreover, they simultaneously increase the levels of light pollution for astronomers. The problem is simple: most lighting fixtures do not properly aim the light they produce downward. In fact, up to fifty percent of the light rays escape upward, thus wasting a significant amount of energy and severely degrading the environment in which to do astronomy. To resolve these problems, I first created a scale model of Millikin University's campus and took time exposures and photometer readings from the replicas of the existing light fixtures. I then fastened improved fixtures to the scaled lamps and retook the camera exposures and photometer readings for comparison. With this information I was able to take my work full scale and physically change one of the light fixtures on campus. Finally to wrap up my project I took my findings to safety and security to show the improvement that these new fixtures represented to Millikin's safety and to its astronomy equipment. [Preview Abstract] |
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S1.00051: Can Airports be a Green Source of Energy? Daniel Solus, Charysse Archer, Brandi Malone, Norrisha Chesterfield, Lateria Jackson, Daniel Erenso When Boeing 747 lands its energy (896MJ) is dissipated by friction. Our statistical analysis for commercial aircrafts landing at the Nashville International Airport (BNA) have discovered that nearly 30 average single family households can be powered by the dissipated energy on a monthly basis. It may be possible to land an airplane on a frictionless surface and transform its energy into electrical energy. To demonstrate this we have conducted theoretical and experimental studies using a conducting rod attached to a toy car sliding on a U-shaped conducting wire placed in a uniform magnetic field track. The results concluded that this technique requires a very strong magnetic field. We then used a cylindrical magnet mounted on toy trucks and set to roll on a track inside a solenoid and been able to generate an ac voltage (4-10 volts). [Preview Abstract] |
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S1.00052: Dipole-Dipole Interaction of a Non-Linear Pendulum Vy Tran, Jason Radel, Lauren Edge, Martin Johnston We have studied the effect of adding a magnetic dipole to a chaotic pendulum.~ The dipole pendulum is subject to both gravitational and magnetic fields.~ The interplay between the shape of the potential well and the resulting motion is shown by Poincare sections in phase space and bifurcation diagrams in coefficient space. We have created computer models which integrate the differential torque equation.~ Using measured coefficients which describe the physical properties of the system and various drive frequencies, we have studied the correlation between predicted Poincare sections and experimental data. The fractal properties of the chaotic attractors in phase space have also been studied in an effort to quantify the complexity of the attractors. [Preview Abstract] |
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S1.00053: Measuring Coefficients of Friction for Materials Commonly Used in Theatre Robert Mentzer, Eric Martell While designing a stage setup for a theatrical presentation, designers must consider equipment, materials, cost and manpower, and we can use physics to simplify and enhance the process. Unfortunately, there is a lack of information about the properties of materials commonly used in theatre. The objective of this research was to determine the coefficients of static and kinetic friction for several materials commonly used in theatrical scene construction and the coefficients of rolling friction for a series of commonly used casters. Materials of known coefficients were tested to confirm the accuracy of the experimental process. Data was collected using a sled style apparatus and LabVIEW software. Data was analyzed in mass volumes using Microsoft Excel spreadsheets and macros. This research was performed as a part of the Physics of Theatre project, a joint collaboration between Millikin University and the University of Illinois at Urbana-Champaign, and was supported in part by Millikin, UIUC, and the United States Institute for Theatre Technology. [Preview Abstract] |
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S1.00054: Modeling and Simulation of the Impact Response of Filled and Unfilled Linear Cellular Alloys for Structural Energetic Material Applications Adam Jakus, Anthony Fredenburg, Naresh Thadhani We are investigating the mechanics of impact-induced stress transfer between a linear cellular alloy (LCA) and a reactive filler to determine the effect of cell geometry on deformation and fragmentation. LCAs are honeycomb structures made of maraging steel, and provide structural integrity for the reactive filler such as a powder mixture of Ta+Fe$_{2}$O$_{3}$. 3-D computations are used to determine stress and strain distributions in both filled and unfilled LCAs during impact. The strength and failure models used for maraging steel and the response of Ta+Fe$_{2}$O$_{3}$ are validated through experiment. The failure response of three different geometries: 9-cell, pie, and reinforced pie, are compared with the response of a hollow cylinder, for impact velocities of 100, 200, and 300 m/s. Unfilled, the cylindrical geometry provides the least resistance to deformation and fragmentation, while the reinforced pie LCA provides the most resistance. Understanding of the mechanics of deformation and failure is used to determine the most effective geometry for stress transfer to the filler. [Preview Abstract] |
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S1.00055: An Ab-Initio Study of Multiple Conformers of Glycine Daniel Kaplan, Hanyu Zhang The recent combination of new computational chemistry techniques and high performance computational hardware is allowing unprecedented levels of accuracy in the calculations of physical quantities such as potential energy surfaces and rotational-vibrational spectra. In this work, we present calculations of the four most stable conformers of Glycine using the aug-cc-pVDZ basis set and Coupled Cluster Theory. We compare our calculations to experimental values and show that our current calculations differ by less than two percent from measured values, much better than results from previous years. When searching for molecules in the Interstellar Medium this small difference suggests that computational methods are becoming well-suited for the task. The natural question to ask is: at what point will the small deviation from experimental values render our computations just as reliable as experiments? We feel that the current results show that we are indeed close to this goal. [Preview Abstract] |
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S1.00056: Arsenic adsorption and speciation in drinking water by GAC-based iron-containing adsorbents Yewon Gim, Jeff Terry, Zhimang Gu, B. Hua, Baolin Deng Granular Activated Carbon (GAC) with Iron adsorbents were developed for effective removal of arsenic from drinking water. The structure and proposed mechanism for As removal was studied using X-ray absorption spectroscopy. The oxidation state of As(III)GAC sample was calculated using XANES spectra and verified to be predominantly As(V). The structure was determined using EXAFS spectra of As(V) and Fe. The Fe spectra suggested thin layer of Fe oxide formation on GAC surface. As data showed As oxide formed bond on the Fe oxide surface. The spectra were calculated using multiple geometrically optimized models calculated using density functional theory. Further calculations were done to verify the structure, and further examine the structure. [Preview Abstract] |
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S1.00057: Formation of synthetic structures with micron size silica beads using optical tweezer Jeremy Curtis, Adam Shulman, Samuel Elrod, Daniel Erenso Colloidal particles, such as silica, are particles having size ranging between several nanometers and several millimeters and can be suspended in a liquid. Because of their tunability, in size, shape, as well as in chemical composition, and their ability to self-assemble they find applications in the development of advanced materials like photonic crystals. Typically, colloids self-assemble into face centered cubic or body centered cubic structures which determines their optical and electrical properties. The control over the structures of one-component colloids using array of optical tweezers, without changing the liquid chemical composition, is limited. If we cut off the laser, then the colloids will eventually lose their new structure. However, by changing the chemical composition of the liquid in which the colloids are suspended in and using optical tweezers, it is possible to assemble the colloids in a new stable structure which possibly results in new optical and electrical properties. In this work, we have demonstrated that micron-size silica beads can in fact be arranged in desired synthetic structure using an optical tweezer in a saline buffered solution. In a 3.1 micron silica colloids suspended in water we added the right concentration of NaCl to form a solution in which silica beads brought close to one another can bind by an adhesive electrostatic force without drifting away due to their thermal energy. Then by trapping and dragging one bead at a time using an optical tweezer, we have arranged the silica beads in one- and two-dimensional structures. [Preview Abstract] |
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S1.00058: A hydrocolloid-based photoelastic modulator Kyle Braun, James Thielen, James Kavanaugh, Christian Lytle, Adam Green, Martin Johnston Birefringent gelatin and other hydrocolloids can serve as the optical elements of simple, inexpensive photoelastic modulators. Driven harmonically by a speaker coil, a small block of gelatin acts as a variable linear retarder and can thus be used to sinusoidally vary the polarization of a laser beam passing through it. We model this effect with Mueller matrices and show that our gelatin modulator behaves as predicted. This uncomplicated yet versatile device is well suited for several types of polarimetry experiments that do not require high precision, and it makes an excellent pedagogical tool for students in advanced undergraduate optics course. [Preview Abstract] |
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S1.00059: Stock sheets of polycarbonate as inexpensive low-order optical wave plates James Kavanaugh, Adam Green We show that commercially available transparent polycarbonate sheets often have linear retardances in the quarter- to half-wave range for visible light. Sheets with thicknesses from 1/16'' to 3/16'' act as zero- to third-order retarders that are modestly stable with temperature and uniform with position. By adjusting the sheets' tilt and orientation angles, they can be tuned to desired retardances, although they are not as sensitive to these parameters as are higher-order wave plates. Since they are readily available and inexpensive, these sheets make good candidates as easily machined, large-aperture wave plates for general laboratory use. [Preview Abstract] |
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S1.00060: LRO, LEND and the Search for Water on the Moon Jesus Cantu For complete abstract, please see session F1. [Preview Abstract] |
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S1.00061: Improving the Higgs Mass Resolution by Using a Neural Network to Make Jet Corrections in the ZH --$>$ l+l-bb Channel Jessica Hanzlik For complete abstract, please see session F1. [Preview Abstract] |
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S1.00062: Development of Neutron Diagnostics for 1 MA Z-Pinch Christopher Thomas For complete abstract, please see session F1. [Preview Abstract] |
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S1.00063: Calibration and Installation of the UConn O-TPC at TUNL Alexander Young For complete abstract, please see session F1. [Preview Abstract] |
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S1.00064: Atmospheric Muon and Neutrinos in IceCube Neutrinos Observatory Ryan Birdsall The goal of the IceCube Neutrino Telescope is to detect high-energy neutrinos of extraterrestrial origins. The flux of neutrinos produced by the impact of cosmic rays in the Earth's atmosphere constitutes an irreducible foreground among which cosmic neutrinos are searched. Therefore the detailed measurement and knowledge of the atmospheric neutrinos is fundamental. Extensive air showers initiated by high energy cosmic ray particles have been simulated using CORSIKA generator, with Hoerandel polygonato model of cosmic ray spectrum and composition, and with three different high energy interaction models: QGSJET01, QGSJET-II, AND SIBYLL. With these models, the ``conventional'' muon and neutrino fluxes, i.e. from the decay of pions and kaons in the atmosphere, have been generated. The resulting muon bundle energy spectrum and mu+/mu- ratio as a function of energy, is compared with various experimental results, such as MINOS, L3Cosmic, and other underground detectors, and with various mathematical calculations. Since muons and neutrinos are produced by the same physical processes, these direct comparisons are used to assess the dependency of neutrino flux on the different interaction models at energies above 1 TeV, i.e. relevant for IceCube. The production of mesons with charm quark is also discussed, since neutrinos produced by the decay of such mesons have harder spectrum than conventional neutrinos, and might mimic high energy extraterrestrial neutrinos in km$^3$ neutrino telescopes. [Preview Abstract] |
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