Bulletin of the American Physical Society
APS April Meeting 2018
Volume 63, Number 4
Saturday–Tuesday, April 14–17, 2018; Columbus, Ohio
Session T01: Poster Session III (14:00-17:00)Poster
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Room: Union Ballroom A |
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T01.00001: NUCLEAR PHYSICS |
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T01.00002: Precision Magnet Design Using the Magnetic Scalar Potential Kevin Royal, Benjamin Riley, Andrew Mullins, Hunter Blanton, Benjamin Kistler, Christopher Crawford As more stringent constraints of new physics are set, the search for physics beyond the standard model requires an unprecedented level of precision. An experiment is being planned at the ORNL SNS to measure the electric dipole moment of the neutron with two orders of magnitude higher precision. An important component of this experiment is precision spin transport electromagnetic coils to guide the spin of polarized neutrons and Helium-3 atoms into the spin-precession measurement cell. To design such coils, we use the magnetic scalar potential and numerically solve for the wire paths needed to produce highly uniform magnetic fields. Once the magnetic geometry is known, the coil frame is printed using stereolithography and then hand wound with magnet wire. We will present measurements of field uniformity while driving the coil with a low-frequency AC current to filter out the earth's background fields. [Preview Abstract] |
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T01.00003: Gamma-Neutron Waveform Discrimination for the KOTO Experiment Noah McNeal The KOTO experiment is a high-energy particle physics experiment located at the J-PARC research facility in Tokai, Japan. The goal of the experiment is to measure the branching ratio (BR) for the neutral kaon decaying into a neutral pion and two neutrinos. This decay is rare and takes place via a directly CP-violating process. The BR predicted by the Standard Model is less than 1 per 30 billion. Due to the rarity of this decay, it has yet to be observed; however, an experimental BR measurement will either confirm Standard Model predictions or indicate new physics. The neutral particle beam is created from protons on a gold target. Neutrons are produced with neutral kaons. A fraction of these interact with the Cesium Iodide (CsI) detector and produce a signal similar to the signature 2-photon signal of our target decay. As a countermeasure, we will install hardware to allow both upstream and downstream signal readouts of the CsI. The timing difference of the measurements allowsus distinguish neutronsand photons. To prepare for this upgrade, we have performed a ``tail-to-total'' method of waveform differentiation to achieve thegamma-neutron discrimination. This poster will present the analysis of the method and results on an optimal method to suppress the neutron background. [Preview Abstract] |
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T01.00004: Q-method Analysis for the Muon g-2 Experiment at Fermilab Fang Han, Tim Gorringe, Wesley Gohn, Renee Fatemi, Laura Kelton The Muon g-2 Experiment (E989) at Fermilab aims to measure muon anomalous magnetic moment $a_\mu$ to a precision of 140 ppb. Experimentally $a_\mu$ is extracted from the precise measurement of the storage ring magnetic field $B$ and the anomalous precession frequency $\omega_a$. E989 plans to reduce the statistical errors by a factor of four compared to the most recent measurement. Such a goal is only worthwhile if the systematic errors are well controlled. The previous measurement extracted $\omega_a$ by a method based on fitting of calorimeter pulses and constructing the time distribution of high-energy positrons. A new technique called Q-method is also proposed for E989 and is now under development. The Q-method extracts $\omega_a$ from the variation of the integrated energy deposited in the calorimeters by the decay positrons. Compared to the standard method, the Q-method has reduced sensitivity to pulse pile-up and time-dependent gain change although greater sensitivity to time-dependent pedestal variations. This talk will discuss the merits of the Q-method analysis and provide an update on the state of the analysis as g-2 embarks on its first physics run. [Preview Abstract] |
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T01.00005: High Resolution Spectrometer (HRS) Detector Efficiency in GM$_{\mathrm{\mathbf{P}}}$\textbf{ Experiment (E12-07-108) at JLab } Bashar Aljawrneh, Abdellah Ahmidouch, bogdan Wojtsekhowski, Barak Schmookler, Eric. Christy, Thir Gaitam, Longwu Ou, Yang Wang The GM$_{\mathrm{p}}$ experiment in Hall A at JLab is the first experiment to complete the data collection after the CEBAF 12 GeV upgrade. The goal of the experiment is to make a precise measurement of the elastic proton cross section at high Q$^{\mathrm{2}}$ to probe the internal structure of the proton. As the GM$_{\mathrm{p}}$ experiment requires a good control of all systematic uncertainties, several novel techniques were developed to accurately extract detector efficiencies for the new standard Hall A detector stack. The latter consists of two HRS spectrometers which are almost identical in architecture and operation. Each spectrometer is comprised of two scintillator detectors for triggering and cosmic suppression, three chambers for tracking, a gas Cherenkov detector and a lead-glass calorimeter for particle identification. Individual scintillator efficiencies and combined trigger efficiency were extracted. In addition, off-line electron cut efficiencies in the gas Cherenkov and calorimeter detectors were studied to limit any potential pion and other contaminations. Lastly, calculations of the computer and electronic live-times were determined for all collected data. [Preview Abstract] |
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T01.00006: New Ice Age And Dark Impact After 15 years Dayong Cao “Diminishing solar activity may bring new Ice Age by 2030” https://astronomynow.com/2015/07/17/diminishing-solar-activity-may-bring-new-ice-age-by-2030/ The paper supports my supposition. http://meetings.aps.org/link/BAPS.2012.APR.K1.78 There is a balance system between the sun and the dark sun. The system of dark sun periodic impact the sun system (it be called dark impact)and cause ice age and extinction. New dark impact and ice age will come in 2030. According to a balance between both structure of solar system and structure of dark solar system, and balance between nuclear fusion of sun and dark nuclear fusion of dark sun, the relationship between dark impact and ice age will be considered. [Preview Abstract] |
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T01.00007: Nucleosynthesis COnstraints on the Explosion Mechanism for Type IA Supernovae Grant Mathews, Kanji Mori, Toshitaka Kajino, Toshio Suzuki, Peter Garnavich, Roland Diehl, Shing-Chi Leung, Kenichi Nomoto, Michael Famiano We consider observational constraints from iron-group elemental and isotopic ratios, to compare with various models. The nucleosynthesis is sensitive to highest white-dwarf central densities. Hence, nucleosynthesis yields can distinguish high-density Chandrasekhar-mass models from lower-density burning models such as white-dwarf mergers. We discuss results of post-processing nucleosynthesis from a number of representative models. These include 1D explosion models (deflagration and/or delayed detonation models) along with 2D and 3D explosion models (including deflagration, delayed-detonation, or a violent merger models). We identify some trends in observations and the models. We compare the models with elemental and isotopic rations from two observed supernovae and three supernova remnants. We find that the models and data tend to fall in two groups. In one group low-density cores such as in 3D merger or deflagration models are most consistent with the nucleosynthesis data, while the other group is best identified with higher-density cores such as in single-degenerate !D delayed detonation models. Hence, we postulate that both types of environments contribute nearly equally to observed SNIa. [Preview Abstract] |
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T01.00008: Identification of semi-muonic $\Lambda$ decays using machine learning models Lottie Murray, Sethin Burrier, Michael McCracken The semi-leptonic decays of strange baryons have played an important role in the development of the Standard-Model electroweak interaction. The muonic decay of the $\Lambda$ baryon, $\Lambda \rightarrow p \mu^- \overline{\nu}$, however, is relatively poorly characterized, with a world database of only 28 events. Better characterization of this decay could constrain several types of beyond-SM interactions, but such measurements are made difficult by an irreducible background from the primary decay mode ($\Lambda\rightarrow p \pi^- \rightarrow p \mu^- \overline{\nu}$) which produces the same final state with similar kinematics. Past measurements of the decay were performed with bubble chamber experiments, in which background events were identified by kinks in prospective $\mu^-$ tracks. Modern hadron spectroscopy experiments provide advantageous kinematics and statistics for investigating these decays, but are not capable of directly identifying intermediate vertices. However, modern multi-variate classification techniques such as deep neural networks may allow for sufficient reduction of background. We present an investigation of the effectiveness of several machine learning models in classifying signal and background for this reaction using a Monte Carlo simulation. [Preview Abstract] |
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T01.00009: Antineutrino-Induced Charge Current Quasi-Elastic Neutral Hyperon Cross-Section on Argon in ArgoNeuT Samuel Borer This poster will cover work done on the first topological and calorimetric study of the cross section measurement of antineutrino-induced charge current quasi-elastic (CCQE) neutral hyperons in liquid argon. This study is being conducted in the Argon Neutrino Test (ArgoNeuT) experiment at Fermi National Accelerator Laboratory. ArgoNeuT is a liquid argon time projection chamber (LArTPC), which provides full 3D-imaging, excellent particle identification capability, precise calorimetric energy reconstruction, and represents the most advanced experimental technology for neutrino physics. This project uses 1.2x10\textasciicircum 20 protons-on-target, in the NuMI beam operating in the low energy antineutrino mode. The reconstruction and analysis techniques developed and improved in this study can be applied to a wide variety of future LArTPC experiments. CCQE Neutral Hyperons are induced exclusively by antineutrinos and can be used as an ``antineutrino tagger'' for larger experiments. This poster will present analysis techniques and preliminary findings for the CCQE neutral hyperon cross section in liquid argon. [Preview Abstract] |
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T01.00010: Status of single phase and dual phase DUNE protodectors at CERN Michelle While, Jaroslaw Nowak Liquid Argon Time Projection Chamber (LAr TPC) is currently the most attractive technology for neutrino oscillations studies. Not only LAr TPCs are cost-effective and scalable to multi-ton scales, but they are also excellent calorimeters and can 3D reconstruct the tracks of ionising particles arising from neutrinos decay products. Future giant liquid Argon TPCs, at the ten-kiloton level, are now at the design and prototyping stage in the context of the Deep Underground Neutrino Experiment (DUNE). DUNE will comprise four 10 kton LAr TPC modules placed at the Sanford Underground Research Facility (SURF) in South Dakota (USA). To gain experience in building and operating such large-scale LAr detectors, two prototypes are currently under construction in the extension of CERN north experimental hall area (EHN1) which eventually will be exposed to the SPS beam. The prototypes consist of a single-phase LAr TPC, called ProtoDUNE Single-Phase (SP), and a dual-phase LAr TPC, called ProtoDUNE Dual- Phase (DP). The cryostats hosting the detectors have been already completed, and construction of the TPCs is already ongoing. The detectors will be assembled by 2018. An overview of the status and progress of both detectors and how they fit in the general context of DUNE will be addressed in this talk. [Preview Abstract] |
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T01.00011: Back-Shifted Fermi Gas Model and Nuclear Level Density Jiafeng Chen, Roman Senkov Nuclear level density (NLD) represents an important ingredient for the theory of nuclear reactions. In most of the cases relevant to nuclear astrophysics, where experimental information is not available, the reaction rates for medium and heavy nuclei can only be estimated using the Hauser-Feshbach approach, which requires the knowledge of NLDs. In this research, we use NLDs calculated within the Shell Model approach and compare them with~the~standard phenomenological approaches, such as Fermi-Gas and Back-Shifted Fermi-Gas models. The more specific goal of this research is to fit the parameters of these phenomenological approaches,~such as temperature parameter,~and~to~study their behavior~across the~nuclei~in~\textit{sd-}shell~model space. We also studied the~effect~of pairing correlations~on~level density. We found that the~pairing gap parameter, which is usually introduced to take into account the~odd-even effect, does not cause much impact~on~the value of the~temperature~parameters. [Preview Abstract] |
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T01.00012: Gamma Coincidence Measurements of $^{192}$Ir from Fusion-Evaporation Reactions T. W. Warren, J. W. McClory, G. J. Lane, C. J. Chiara, J. J. Carroll Doubly odd $^{192}$Ir plays host to several metastable states, with the 168 keV, 11$^{-}$ isomer ($^{192m2}$Ir) having a notable 241-year half-life. Should a reliable mechanism for on-demand depletion of the m2 isomer be identified, $^{192}$Ir could serve as an energy storage medium. The first step toward an application of this nature requires isolation of a precise depletion pathway. Such a path will only be evident through detailed structural knowledge of the nucleus, especially at high spins where population and depopulation of the isomer likely occur. To that end, recent experiments, involving gamma spectroscopy of fusion-evaporation reactions, were performed with the CAESAR gamma-ray detector array and 14UD electrostatic tandem accelerator at the Australian National University Heavy Ion Accelerator Facility. In particular, in-beam measurements of $\gamma$-$\gamma$ coincidences were collected for the $^{192}$Os(p,n)$^{192}$Ir and $^{192}$Os(d,2n)$^{192}$Ir reactions. Calibrations and spectral analyses of the pair coincidences were conducted using the \textit{RadWare} tool suite. Analyses enabled construction of a preliminary level scheme for comparison with existing theoretical predictions of $^{192}$Ir rotational structure based on the two-quasiparticle rotor model. [Preview Abstract] |
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T01.00013: Development of an electron impact ionization source for the CHIP-TRAP apparatus Madhawa Horana Gamage, Ramesh Bhandari, Nadeesha Gamage, Rachel Sandler, Matthew Redshaw At Central Michigan University, we are developing a high-precision Penning trap (CHIP-TRAP) for precise mass measurements with stable and long-lived isotopes. Ions will be produced using external ion sources and then transported to the Penning trap at low-energy using electrostatic ion optics. Ion sources that will be utilized with CHIP-TRAP include a laser ablation ion source (LAS) that has already been commissioned, and a low current electron impact ionization (EII) source that is currently being developed. The LAS enables ion production from solid targets, while the EII source will enable ion production from gaseous samples. The EII source is a Penning ion generator style source, consisting of a permanent neodymium ring magnet, cylindrical Penning trap, and low current thermal emitter. Ions will be produced via EII of gas admitted into the trapping region, then released in a bunch and transported to the CHIP-TRAP beam line. In this poster we will describe simulations and the design of the EII source and report on the status of its construction and implementation. [Preview Abstract] |
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T01.00014: GEM detector as an active sieve for the super high momentum spectrometer in Hall-C at the Jefferson Lab Md Latiful Kabir The Super High Momentum Spectrometer (SHMS), designed to perform high resolution and high accuracy nuclear physics experiments, was built as the major Hall-C component of the 12-GeV upgrade project and has already started its operation early this year. In order to reach forward scattering angles of 5.5$^0$ and to increase the solid angle of the spectrometer, the SHMS has a 3$^0$ horizontally-bending superconducting dipole magnet as its first magnetic element. Because the SHMS has both horizontal bend and vertical bend, in addition to the passive sieve, an active sieve collimator is required for the optics calibration and understanding the magnets. I will talk about how a Gas Electron Multiplier (GEM) detector and associated readout electronics are used to fulfill this requirement. [Preview Abstract] |
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T01.00015: Status of CHIP-TRAP: The Central Michigan University High-Precision Penning Trap Nadeesha Gamage, Madhawa Horana, Rachel Sandler, Ramesh Bhandari, Matthew Redshaw At Central Michigan University we are developing a high-precision Penning trap (CHIP-TRAP) for precise mass measurements with stable and long-lived isotopes with application, for example to neutrino mass determinations with 187Re and 163Ho. CHIP-TRAP will consist of a pair of hyperbolic precision measurement traps and a cylindrical capture/filter trap located in a 12 T magnetic field. Ions will be produced using a laser ablation ion source (LAS) and transported to the capture trap at low-energy using electrostatic ion optics. In the capture trap ions will be identified via Fourier Transform Ion Cyclotron Resonance (FT-ICR) techniques, and unwanted ions will be removed. The ion of interest will then be moved to one of the precision measurement traps. The goal is to simultaneously measure the cyclotron frequency of single ions of two different species, each confined in one of the precision measurement traps, via phase sensitive image charge detection techniques. This will result in a cancellation of magnetic field fluctuations and a reduction in statistical uncertainty. In this presentation we will report on the design, construction, and testing of the LAS and beam-line and on the overall status of the CHIP-TRAP project. [Preview Abstract] |
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T01.00016: ASICs for FRIB Daniel Hoff, Jon Elson, Lee Sobotka, George Engel Historically, analog signal processing systems have been large and cumbersome, but the production of ASICs for analog signal processing has proved to be a cost-effective solution for creating large channel-count (100’s and up) detector systems. Aside from those for TPC’s, the SIUE-WUSTL effort, reviewed in this talk, is the sole effort in the US invested in making ASICs for use at FRIB. Two new versions of existing chips and one new chip are currently under design and/or production. The most recent HINP ASIC, widely used for modest-to-large arrays of Si detectors, provides two active gain ranges but does not allow an external charge-sensitive (pre)amplifier (unlike the previous version). The next version will return the external CSA option, retain the dual-gain shapers and be compatible with a dual-gain CSA ASIC designed at RIKEN. A second, and greatly improved, PSD ASIC – with three gated integrators per channel - has been designed and fabricated and the support electronics are currently being upgraded. A 16-ch CFD ASIC has been designed and will be fabricated in 2018. The PSD+CFD chips are designed to work together to allow for large channel count arrays of scintillators with n/$\gamma$ or charged-particle differentiable signal forms. [Preview Abstract] |
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T01.00017: Exploring the use of Gantt charts for managing high-energy physics analyses Jamie Bedard Gantt charts are a visualization tool used in long-term project planning to keep track of multiple tasks and goals, some of which may depend on the completion of other tasks. The ability to see and coordinate many parallel or serialized tasks is critical to construction projects that operate on deadlines and with finite budgets. This is similar to many thesis or related research projects where there are many moving parts, a defense date that needs to be satisfied, and an advisor who has a fixed amount of money to support the student or post-doc. An added challenge for new graduate students is that it is difficult to see the entire scope of their project and all the relationships between tasks and they may not develop this understanding until the project is actually completed! We are exploring the use of Gantt charts as an organization tool for analyses within CMS, both as a learning tool and for the purpose of tracking progress on any given study. We have collected responses from members of the CMS collaboration as to whether or not this type of tool would be effective and also tried to learn how analysts see the different parts of their project. The results of this survey will be presented. [Preview Abstract] |
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T01.00018: On the Gluon Spectrum in the Boost-Invariant Glasma from a Semi-Analytic Approach Ming Li In high energy heavy-ion collisions, the degrees of freedom at the very early stage can be effectively represented by strong classical gluonic fields within the color glass condensate framework. As the system expands, the strong gluonic fields eventually become weak such that an equivalent description using the gluonic particle degrees of freedom starts to become valid. I will discuss the spectrum of these gluonic particles from a semi-analytic approach by solving the classical Yang-Mills equations using a power series expansion in the proper time. I will show that the chromo-electric fields have larger contributions to the gluon spectrum than the chromo-magnetic fields do. Furthermore, the large momentum modes take less time to reach the weak-field regime while smaller momentum modes take more time. The resulting functional form of the gluon spectrum is exponential in nature and the spectrum is close to a thermal distribution, with effective temperatures around $0.6\,Q_s$ to $0.9\,Q_s$ late in the Glasma evolution. [Preview Abstract] |
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T01.00019: PARTICLES AND FIELDS |
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T01.00020: Search for Non-resonant excesses from Contact Interactions and Large Extra Dimensions in $\mu^+ \mu^-$ and $e^+ e^-$ Final States in 13 TeV p-p Collisions at CMS Shawn Zaleski We report results on the search for contact interactions (CI) and large extra dimensions (LED) using data collected during the 2016 run, in proton-proton collisions at the sqrt(s) = 13 TeV by the Compact Muon Solenoid experiment at the Large Hadron Collider at CERN. The analyzed data correspond to luminosities of about 36 $fb^{−1}$. The results, for CI, are interpreted in the context of left-left, left-right, and right-right helicity quark and lepton compositeness models with an energy scale parameter $\Lambda$. The LED model, with exchange of gravitons, is characterized by energy scale parameter $\Lambda_T$. Using information from the invariant mass distribution we set 95{\%} confidence level lower limits on $\Lambda$, for both destructive and constructive interference models, and on $\Lambda_T$. [Preview Abstract] |
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T01.00021: Transient Magnetic Field Analysis for Muon g-2 Experiment Alexander Tewsley-Booth There is currently a $3.5\sigma$ discrepancy in the Standard Model prediction and experimental values of the anomalous magnetic moment of the muon. The Muon g-2 collaboration at FermiLab (E989 experiment) seeks to investigate this discrepancy with a new precision measurement as a test of the Standard Model, which is also uniquely sensitive to possible new physics. This experiment builds on the previous work done at Brookhaven E821 by improving statistical errors and systematic errors, both in positron counting and magnetic field measurements, with an expected overall uncertainty of 140 ppb (a factor of four improvement over the previous experiment). One of the improvements to the magnetic field measurement is a suite of fluxgate magnetometers that are sensitive to transient magnetic fields as small as 10 nT with a bandwidth of 1 kHz, which are important to understand and quantify to very high precision. Methods for identifying, measuring, and analyzing transient fields in the experimental hall with the fluxgate magnetometers will be presented. [Preview Abstract] |
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T01.00022: Search for Di-Higgs Resonance at the ATLAS Experiment Peace Kotamnives, Eric Torrence With the question remaining whether there is only one Higgs boson or several, our research studies how a heavier Higgs boson could be found in the ATLAS data at the LHC. By the pure Standard Model phenomenon, we expect to find production of two SM Higgs bosons from the tri-linear Higgs coupling. However, the rate at which this will happen is far below what we will be able to see for many years at the LHC. As the discovered Higgs boson can decay to different pairs of particles, and the rate is expected to be proportional to the mass of the decay particle involved, the most likely decay channel is H$\to $bb at 33{\%}, and the second most likely channel is H$\to $WW at 25{\%}. Therefore, HH$\to $bbbb channel has the highest rate of production, but HH$\to $WWbb channel is chosen due to higher backgrounds in the four-b channel. In addition, two W bosons could decay into two quarks, one lepton and its neutrino. The performance of identifying HH$\to $WWbb events for large heavy Higgs mass has studied specifically by using boosted object tagging. From the detector, we expect collimated jets from b quarks merging into a fat jet. By applying the relativistic kinematics theory and reducing some major backgrounds, we compare our alternative algorithms with the current algorithm in reconstructing the W$\to $qq candidate. With the improved sensitivity, our expectation is to see a bump on top of the mass distribution indicating the new physics particle that we are searching for. [Preview Abstract] |
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T01.00023: Abstract Withdrawn
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T01.00024: Measuring the cross section of antineutrino-induced charge current quasi-elastic neutral hyperons in ArgoNeuT Samuel Borer This poster will cover work done on the first topological and calorimetric study of the cross section measurement of antineutrino-induced charge current quasi-elastic (CCQE) neutral hyperons in liquid argon. This study is being conducted in the Argon Neutrino Test (ArgoNeuT) experiment at Fermi National Accelerator Laboratory. ArgoNeuT is a liquid argon time projection chamber (LArTPC), which provides full 3D-imaging, excellent particle identification capability, precise calorimetric energy reconstruction, and represents the most advanced experimental technology for neutrino physics. This project uses 1.2x10\textasciicircum 20 protons-on-target, in the NuMI beam operating in the low energy antineutrino mode. The reconstruction and analysis techniques developed and improved in this study can be applied to a wide variety of future LArTPC experiments. CCQE Neutral Hyperons are induced exclusively by antineutrinos and can be used as an ``antineutrino tagger'' for larger experiments. This poster will present analysis techniques and preliminary findings for the CCQE neutral hyperon cross section in liquid argon. [Preview Abstract] |
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T01.00025: Opportunity to study physics beyond standard neutrino oscillations @DUNE Animesh Chatterjee A major goal of present and future long-baseline neutrino oscillation experiments is to make precision measurements of neutrino flavour oscillations, which are well-explained by mixing between three active flavors within current experimental constraints. However, other mechanisms could be responsible for neutrino flavour change on a sub-leading level. The proposed Deep Underground Neutrino Experiment (DUNE) plans to deploy a massive 40 kton Liquid Argon Time Projection Chamber (LArTPC) and expose it to a high-intensity 1.2 MW neutrino beam to measure neutrino flavor change over a 1300 km baseline between Fermilab and the Homestake mine, in South Dakota. This detector-beam configuration provides an excellent opportunity to study physics beyond standard neutrino oscillations. DUNE will be able to search for or constrain a wide variety of physics phenomena, such as, light sterile neutrinos, nonstandard neutrino interactions, large extra-dimensions, heavy neutrinos, lepton flavour violation, and low mass dark matter. In this talk, we will present preliminary DUNE sensitivities to physics beyond the standard model and show that DUNE will play a significant role in measuring or constraining these phenomena. [Preview Abstract] |
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T01.00026: Microscopic Black Holes in the Large Hadron Collider Gage DeZoort, Jiwon Han, Martin Kwok, Greg Landsberg, Chris Neu, Tutanon Sinthuprasith CERN's Large Hadron Collider (LHC) is the largest experimental particle physics facility in the world, capable of colliding protons with energies of up to 13 TeV. Many theoretical models describe exotic new physics that takes place in these high energy collisions, including the production of microscopic black holes. Using recent CERN collision data, we have conducted a search for semiclassical and quantum black holes, as well as string balls, objects predicted by string theory. In conducting this search, we have set limits on the rate of black hole / string ball production for a few specific models. Additionally, we have set model independent limits on the production rate of new physics for certain final states. [Preview Abstract] |
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T01.00027: Superconducting cavity in CAPP's dark matter axion experiment Danho Ahn, Ohjoon Kwon, Dojun Youm, Wonjun Jang, Woohyun Chung, Doyu Lee, Jinsu Kim, Yannis Semertzidis The IBS Center for Axion and Precision Physics Research (CAPP) in Korea searches for axions using a tunable resonant cavity to enhance axion to photon conversion rates to a detectable level when the cavity resonates at the axion mass. The superconducting coat on the inner surface of the cavity could raise the Q-factor significantly, among other possible improvements to enhance the sensitivity of the experiment, but the presence of the high magnetic field prevents it since the type I superconductor loses superconductivity easily even with a small amount of field. I will present the results of measuring Q-factors of the cavity by coating NbTi with RF magnetron sputtering method and applying YBCO tapes to the inner surface of the cavity. [Preview Abstract] |
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T01.00028: Microwave cavity with dielectric material in CAPP's axion search experiment Jinsu Kim, Ohjoon Kwon, Woohyun Chung, Yannis K. Semertzidis The Center for Axion and Precision Physics Research (CAPP) of IBS in Korea is launching a microwave axion search experiment using a high Q-factor, tunable resonant cavity submerged in a strong magnetic field. We are currently searching for axions in the 1.5 to 2.5 GHz (TM010 mode) frequency range, but would like to extend the mass range of search in the future without suffering a volume loss. In order to access high frequencies without much degrading the axion to photon conversion power and the scanning rate of the experiment, a new type of cavity with loss-free dielectric material (sapphire) inside is proposed. With proper geometry of dielectric material, it is possible to create higher modes with larger form factors. The results of various simulation studies and test on this type of resonator using the TM030-like mode will be presented. [Preview Abstract] |
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T01.00029: Bilayer Graphene Aaron Winn, Andrew Jiao, Matthew Walker, John Maier, Juan Velasco, Jeffrey Teo We study the electronic properties of bilayer graphene under an electric and magnetic field. We introduce an alternating electric potential and use a cylindrical geometry to study periodic boundary conditions using the tight-binding model. The potential induces one dimensional exponentially localized chiral channels for electron transport located at the potential interface. Analytical solutions were found in the continuum limit, and perturbation theory was applied to calculate inter-wire coupling when we considered a two-wire system. Finally, a magnetic field perpendicular to the graphene was added to demonstrate Landau levels and to perturb bilayer graphene with a strong parallel electric field. [Preview Abstract] |
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T01.00030: Drift Chamber Tracking and Calibration for CLAS12 Md Latiful Kabir The drift chamber (DC) is one of the essential detectors of the CLAS12 spectrometer to perform high resolution and high accuracy nuclear physics experiments. The DC has been upgraded to meet the luminosity requirement of 10$^{35}$ cm$^{-2}$s$^{-1}$ and was tuned to the fully operational mode at the beginning of 2018. It is designed to measure trajectories and momenta of the charged particle emerging from the target to a spatial resolution of $\sim$ 250 - 350 $\mu$m. It uses the time-based tracking in addition to the hit-based tracking to achieve this resolution. However, the time-based tracking requires the evaluation of the time-to-distance functional form which requires to be well calibrated to improve the DC performance and hence the quality of experimental data. I will briefly talk about the DC tracking and then give details of the DC calibration to achieve the desired resolution. [Preview Abstract] |
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T01.00031: NOvA Event Reconstruction Techniques Andrew Sutton The NO$\nu$A experiment measures long-baseline neutrino oscillations using the NuMI beam at Fermilab. The experiment uses liquid scintillator tracking calorimeters with a 300 ton Near Detector located underground, and a functionally-identical 14 kiloton Far Detector on the surface 810 km away. The detector location pose separate challenges. The Near Detector captures multiple overlapping neutrino events in each spill while the Far Detector, being on the surface, has a significant cosmic ray background. The neutrino appearance/disappearance analyses require accurate event reconstruction to measure the neutrino flavor and energy in each interaction. Likewise, the Near Detector cross section analysis relies on accurate identification of the particle content resulting from an interaction. This poster will describe the methods developed to separate events in time and space, locate interaction vertices, reconstruct particle tracks, and identify particles. [Preview Abstract] |
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T01.00032: HADRONIC PHYSICS |
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T01.00033: Exclusive $\pi^0$ production and Compton scattering at GlueX Zachary Baldwin The GlueX experiment in Jefferson Lab’s Hall D aims to explore the gluonic degrees of freedom within hadrons through high-energy meson photoproduction. Using a 9 GeV linearly-polarized photon beam, the first measurements of the $\Sigma$ beam asymmetry for pseudoscalar production have already provided insight into the meson production mechanisms at these energies. In this work, studies of the reaction $\gamma p \rightarrow \pi^0 p$ will be presented along with an exploratory study of the Compton scattering process $\gamma p \rightarrow \gamma p$, utilizing the fine-grained calorimetry of the GlueX experiment. [Preview Abstract] |
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T01.00034: Measurement of the LHCb Pentaquark double polarization and photo-production coupling in Hall A at Jefferson Lab Cristiano Fanelli, Lubomir Pentchev, Bogdan Wojtsekhowski We investigate the possibility to measure the helicity correlation asymmetry $K_{LL}$ in J/$\psi$ photo-production using circularly polarized photons from a proton target with detection of the recoil proton polarization. This experiment can offer a very high sensitivity to the LHCb pentaquark state decaying into J/$\Psi$ p in the s-channel exclusive production process due to first order effect of the resonance in the polarization observables. This measurement can take advantage of the high luminosity of the Super Bigbite setup developed for GEp/SBS experiment in Hall A combined to the large figure of merit related to the polarimetry technique. Preliminary results of this feasibility study will be shown and the analysis strategy outlined. The possible achievable physics goals will be also addressed. [Preview Abstract] |
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T01.00035: FEW BODY SYSTEMS |
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T01.00036: The broadening effects on para-Nitroaniline' two-photon absorption cross-section. Tarcius Ramos, Daniel da Silva, Sylvio Canuto The theoretical two-photon absorption (TPA) cross-section depends on the incident photon energy ($\omega )$, the TPA transition probability ($\delta )$ and the spectral broadening ($\Gamma )$. The $\omega $ and $\delta $ are obtained employing the quantum-chemical calculations, however it is not well defined a procedure to obtain $\Gamma $. This broadening must cover the homogeneous and inhomogeneous effects due to temperature and interactions with the environment, being the value of 0.1eV often used. We propose a way to obtain the TPA from molecular simulations, fitting the $\Gamma $ to obtain equivalent theoretical and experimental spectra. The TPA of the para-Nitroaniline (pNA) was calculated for three solvents using our procedure with the rigid Monte Carlo (MC) simulation. Our theoretical values are less than 25{\%} higher than experiment. We also performed expensive ab initio BOMD simulations of the pNA isolated and in explicit water and the results of TPA cross-section are equivalent with those obtained by MC. The broadening effects were also analysed from the variance of the transition energies using BOMD simulations and the results found again to be equivalent. The interaction effects between pNA and the water solvent increases the spectral broadening by 0.15eV compared with the isolated case. [Preview Abstract] |
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T01.00037: Lower bounds for quasi-bound state energy of three-Body kaonic clusters Roman Kezerashvili, Igor Filikhin, Branislav Vlahovic The kaonic clusters $K^{-}K^{-}p$ and $ppK^{-}$ are described based on the configuration space Faddeev equations for $AAB$ system. The $AB$ interaction is given by phenomenological isospin-dependent potentials. We show that the relation $\left\vert E_{3}(V_{AA}=0)\right\vert~<~2\left\vert E_{2}\right\vert$ is satisfied when $E_{2}$ is the binding energy of the $AB$ subsystem and $E_{3}(V_{AA}=0)$ is the three-body binding energy and $V_{AA}$ is the interaction between the identical particles. For the $NN{\bar K}$ system, taking into account weak attraction of $NN$ interaction the relation leads to the evaluation $|E_3|\le 2|E_2|$. [Preview Abstract] |
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T01.00038: RADIATION SOURCES |
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T01.00039: Assessment of Natural Radionuclide Concentrations and Elemental Compositions of Twelve Herbal Plants used for the treatment of malaria in Ibadan South West Local Government, Oyo State, Nigeria Adetomiwa Alade, Adekunle Adegbile Twelve plants used for treatment of malaria in Ibadan South-West Local Government Area Nigeria have been investigated for natural radionuclides and elemental compositions using gamma spectrometry (NaI(TI)) and atomic absorption spectrophotometry respectively. Relevant radiological hazard parameters were evaluated from the activity concentrations. Results of this study show that the mean activity concentrations of K-40, U-238and Th-232 as 630.03, 5.79 and 4.13Bq/kg respectively. The mean value of the radiological parameters of 0.005mSv/y, 59.9Bq/kg and 31.76nGy/h for average annual committed effective dose, radium equivalent and absorbed dose rates were lower than the world average values of 0.3mSv/y, 370Bq/kg and 59nGy/h respectively for ingestion of natural radionuclides provided by UNSCEAR for any individual. Elemental analyses revealed K, Na, Mg, Ca, Cu, Mn, Zn, Fe, Cr, Ni, Pb and Cd with their levels in the samples lower than the permissible limit. Results for relevant hazard parameters show an insignificant radiological risk which implies no threat due to radiation exposure. The study has shown that plants of this study can provide useful minerals needed for normal growth. [Preview Abstract] |
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T01.00040: Radiation Quantum Analysis of the same speed of light Han Quan Matter is composed of "waves", which converge on the "waves" of atoms and subatoms to form the physical substance. The "waves" that diverge in the outer space make up the space-time substance. Radiation quantum comes from the atomic nuclei inside. They are composed of mutually rotating particle pairs. The radius of the nucleus is on the order of 10$^{\mathrm{-15\thinspace }}$meters, making up the neutron, and the radius of gyration of the particle pairs with protons rotating around each other should be on the order of 10$^{\mathrm{-18\thinspace }}$meters (on the scale of weak interaction). When the nucleus is disturbed, it is bound to occur that the smaller the quantum radius, the easier it is to form. The law of nuclear radiation appears: the radius of the radiation quantum is inversely proportional to the quantity of the radiation quantum. In a certain period of time, r × n $=$ S, where r is the radius of the quantum, n is the quantum number of radiation over a period of time, and S is a constant in meters. Suppose the time is 1 second, S $=$ 3 × 10$^{\mathrm{8\thinspace }}$meters, that is, the distance of light quantum 1 second no matter what the radius of the radiation quantum, a quantum string of 3 × 10$^{\mathrm{8}}$ meters can be formed in one second. [Preview Abstract] |
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T01.00041: Assessment of natural radionuclide concentrations (Norms) in some selected medicinal plants . Adetomiwa Alade In this study, the activity concentration $^{\mathrm{40}}$K, $^{\mathrm{238}}$U and $^{\mathrm{232}}$Th in seven selected medicinal plants collected from Institute of Agricultural Research and Training, Ibadan was reported. Gamma-ray spectroscopy was employed to perform the measurements using a NaI (TI) detector. The average annual committed effective dose (AACED) and annual gonadal equivalent dose (AGED) due to the ingestion of radionuclides from medicinal plants were also estimated. The results of the analysis indicated a mean activity concentration of $^{\mathrm{40}}$K, $^{\mathrm{238}}$U and $^{\mathrm{232}}$Th as 69.42, 5.62 and 1.58 Bq/kg respectively. \textit{Vernonia amygdalinaa} recorded the highest activity concentration for all the radionuclides. The estimated mean value of 0.00104 mSv/yr$^{\mathrm{\thinspace }}$and 45.769 \textmu Sv/yr for AACED and AGED are far below the world average of 0.30 mSv/yr and 300 \textmu Sv/yr$^{\mathrm{\thinspace }}$respectively for ingestion of NORMs provided in UNSCEAR 2000 report for an individual. Therefore, the radiological hazard associated with intake of NORMs in the medicinal plants is insignificant. The results could provide baseline values useful in establishing regulations relating to radiation protection as well as developing standards and guidelines for the use of medicinal plants. [Preview Abstract] |
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T01.00042: ACCELERATORS AND STORAGE RINGS |
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T01.00043: Development of a Near-Relativistic Electron Beam Source using a Pyroelectric Crystal Array Rodney Yoder, Jonathan Jefferson, Daniel Lerner Novel laser-powered acceleration structures currently under development have the potential to produce GeV/m acceleration gradients in a microchip-scale structure. Such structures, which necessarily have dimensions comparable to optical wavelengths, will require injection of a sub-micron-scale electron bunch at near-relativistic energies to achieve high-quality, monoenergetic output beams. One possible injection mechanism relies on field emission from a nanotip array, followed by acceleration in optical or DC fields. We have demonstrated field emission of kilovolt electrons from a carbon nanotube (CNT) layer, using the quasi-DC fields produced by a pyroelectric crystal (lithium niobate) during slow heating and cooling. Results compare well with mathematical models. Further, we describe a method for producing near-relativistic electrons via pyroelectric materials using a similar approach, involving a narrow vacuum channel through the center of a three-crystal array. This arrangement is predicted to produce highly uniform accelerating fields of tens of MV/m, with output energy $>200$ keV, leading to applications as a stand-alone radiation source in addition to injection. A proof-of-principle experiment in this geometry is underway and will be discussed. [Preview Abstract] |
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T01.00044: COMPUTATIONAL PHYSICS |
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T01.00045: h5hep: wrapping HDF5 to achieve a ROOT-like file format Madeline Hagen, Matthew Bellis High-Energy Physics (HEP) datasets are challenging for many file formats because of the inhomogeneous nature of the dataset: one event may have 3 jets and 2 muons and the next event may have 12 jets and no muons. Most file formats excel when the data exists in some simple n x m block structure. The TFile and TTree objects in ROOT handle these datasets incredibly well but require users to import the entire ROOT ecosystem just to read the files, locking out users from other communities that do not use ROOT. h5hep (HDF5 for Heterogeneous Entries in Parallel) is a wrapper to the HDF5 format that gives users access to the ROOT functionality without ROOT and making use of native python tools. The performance of this tool and its application to non-HEP datasets will be presented. [Preview Abstract] |
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T01.00046: Sub-Angstrom Resolution X-Ray Imaging of Correlated Disorder in Crystals Victoria Kovalchuk, Jacob Ruff, Jooseop Lee We implemented a new method, called 3D $\Delta$-PDF for analyzing X-ray diffraction data, and modeled some two-dimensional systems to evaluate the strengths and weaknesses of this method in describing different systems with correlated disorder. We found that our current implementation of the code would require for very large reciprocal spaces in order to give accurate and interesting information about a system. Such sizes of a reciprocal space are not common or easy to attain using current X-ray diffraction methods, and this poses a problem when trying to apply this method to real data sets. [Preview Abstract] |
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T01.00047: Automated Bio-mechanical Modeling of the Human Breast Using the Finite Element Method Andrew Kyung, Joo Hee Lee Creating a patient-specific modeling of the breast tissue is important in various biomechanical applications. FEM (Finite Element Method) is a numerical and computational tool that can be used to perform biophysics analysis as well as mathematical and engineering analysis. The FEM technique allows mesh generations of complex geometry to divide into smaller elements, such as triangles, quadrilaterals, and other two dimensional or three dimensional elements, to model a continuum or solid geometry. In this research, a 3D mesh was efficiently created for breast cancer imaging using FEM software. Pre-processing and post-processing mechanisms for automatic mesh generation of breast was implemented for the breast cancer imaging. In the discretization process, the mesh of the desired shape was created by filling the nodes in the mesh to create the present image for the biophysical analysis, and triangle elements with hyperelastic properties were used to model the surface of the breast. The results show that using the FEM software to model breast tissue led to great savings in computer running time, compared to manual construction. The efficiency of the FEM software was further emphasized for elements with irregular and complex geometry shapes. [Preview Abstract] |
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T01.00048: Thermodynamic Properties of Alcohols Using Molecular Dynamics Simulations. Abdalla Obeidat, Hind Abu Ghazleh Thermodynamic properties of methanol, ethanol and propanol such as: density, surface tension and dipole moment have been estimated as a function of temperature using two different potential functions (OPLS-AA and TraPPE-UA). Our results have been compared to experimental values at low temperatures; from 200K to 300K. The results are quite satisfactory, and one cannot judge the best potential function in studying these unary systems. [Preview Abstract] |
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T01.00049: Combined Automated Geophysical Field Calculator for Wenner, Schlumberger and Dipole Dipole Electrode System. Dannity Isiwele, Monday Alile, Elmer Isiwele This research is a fast and direct approach for solving the geometric factor (k) and the Apparent Resistivity (ρa)for the combined Schlumberger, wenner, and Dipole Dipole electrode configurations in geo-electric field surveys, using the measured quantities of the current electrode and potential electrode spacing respectively.The main features are the potential electrode spacing (M,N), current electrode spacing (A,B), the instant resistance reading (V/I (Ω)) (is the reading from the measuring device, usually a resistivity meter), the Geometric factor (k) and the Apparent Resistivity (p).The ability of the program to modify basic quantities like current electrode spacing, the potential electrode spacing and the V/I to suit individual field practice with respect to the lateral and vertical variations in the inhomogeneous media made it a unique program. On execution of the program, it was found that both the geometric factor (k) and the apparent resistivity (pa ) values are automatically displayed once the respective field data were inputted and the execute button clicked accordingly. The program and model is well suited for any field work in the realm of Schlumberger, Wenner and the Double dipole electrode configurations. [Preview Abstract] |
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T01.00050: Lattice Quantum Chromodynamics and Chiral Perturbation Theory at Low Energies William Charles, Christopher Aubin We explore in detail the results given by unphysical lattice quantum chromodynamics (QCD) simulations with staggered quarks and their relation to staggered chiral perturbation theory (SChPT) at low energies. Analysis of such simulations allows us to examine two phases, depending upon the breaking of specific lattice symmetries: the physical, unbroken phase where the continuum limit of the lattice simulation corresponds to the real world, and a broken phase which has no physical continuum limit. Using previously generated lattice configurations, we numerically measure the mass spectra of pions as a function of the masses of their constituent quarks in order to see if the observed spectra agree with the theoretical predictions given by SChPT. By examining these spectra in the unbroken as well as broken phases we hope to compare the masses of different mesons given by lattice QCD and SChPT to determine whether SChPT is a good effective theory outside of the physical phase. If SChPT is valid then it should correctly predict both physical and unphysical situations at low enough energies. [Preview Abstract] |
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T01.00051: The Role of Tilted Magnetospheres During Black-Hole Binary Mergers Ashok Choudhary, Maria C. Babiuc, Zachariah B. Etienne, Sean T. McWilliams The simultaneous detection of gravitational and electromagnetic waves from the binary neutron star merger GW170817 marked the beginning of multi-messenger gravitational-wave astronomy. Although the mechanisms involved in producing this electromagnetic counterpart are not entirely understood, the most promising explanations for the high energy emission involve the existence of a surrounding magnetic field. Massive black-hole binary mergers are also promising sources for coincident electromagnetic and gravitational wave observations. To better understand and predict these events, we study the time evolution of a black-hole binary system in an initially uniform magnetic field inclined at different angles to the orbital plane, using the recently released general relativistic force-free electrodynamics code, GiRaFFE. We present simulations of a single rotating Kerr black hole, a black-hole binary without spin, as well as work in progress to include a black-hole binary with spin, all immersed in a magnetosphere tilted at various angles with respect to the symmetry plane. We analyze the time evolution of the magnetic field and Poynting flux through a series of diagnostics, and determine the role of the tilt in the emission of electromagnetic radiation during the merger. [Preview Abstract] |
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T01.00052: The complex structure of quark and a new paradigm of physics Rongwu Liu Quark (as well as electron etc) is known as fundamental particle which is usually abstracted as point-like particle carrying fundamental matter mass, electricity, flavor, and color. This author proposes that, fundamental matter flavor and color don't exist in the form of particle, instead, they exist in the form of volume field; fundamental body (such as quark etc) is composed of fundamental particle (mass and electricity) and fundamental volume field (flavor and color) which exists in the form of limited volume. Such that, a new paradigm of strong interaction and weak interaction is proposed: (1) Volume field is the form of material existence in plane space. (2) Volume field takes volume motion. (3) Volume fields have strong or weak interaction between them by means of overlapping volume fields. As displacement motion of particle in point space has the properties of relativity and inertia, volume motion of volume field in plane space has the properties of absoluteness and restoration; as exchanging force of particle has the properties of long-range force, superposition force, central force, and attenuating force, overlapping force of volume field has the properties of short-range force, saturation force, non-central force, and non-attenuating force. [Preview Abstract] |
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T01.00053: Quantum Chaos on 2 spin levels Declan Mulhall Random interactions with global symmetries exhibit regularities in the ensemble average sense. A model system of $N$ bosons on 2 spin levels having random 2-body collisions is examined. Robust regularities (in the ensemble average sense) arise, including the usual ones including ground state spin distributions peaked at extreme values of angular momentum, signatures of rotational bands, and smooth parabolic yrast lines. A simple random matrix theory analysis shows signatures of quantum chaos in the level spacing distribution and the $\Delta_3$ statistic. There are other interesting features including steps in the yrast lines and strong regularities in the in the pair transfer amplitude, as well as other collective features. [Preview Abstract] |
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T01.00054: Controlling electromagnetic waves in a class of invisible materials Yangjie Liu We propose a general methodology to manipulate the amplitude of an electromag- netic wave in a pre-defined way, without introducing any scattering. This leads to a whole class of isotropic spatially varying permittivity and permeability profiles that are invisible to incident waves. The theory is illustrated through various numerical examples, including the non-magnetic case. The implementation of the required material properties using metamaterials is discussed, as well as extensions of the method for controlling the phase of electromagnetic fields. Transformation optics is a powerful analytic tool to design impedance-matched material, which gives rise to scattering-free wave solutions up to designer’s will. However, this method inevitably requires the material parameter to be anisotropic, which complicates its manufacturing process. Therefore, an isotropic material to achieve the required wave solution may solve this issue. Here in this conference contribution, we try to reveal one method to serve the purpose to cater for designer’s requirements for electromagnetic waves. [Preview Abstract] |
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T01.00055: Checkerboard Model Theodore Lach The CBM uses the basic constants of nature (mass and magnetic moment of proton/neutron) and a few simple equations (relativistic mass equation, de Broglie wavelength, and binding energy of He 3) to describe the structure of the proton and neutron and explain the strong nuclear force. The CBM was described over 20 years ago. It was conceived just short of 30 years ago, 1989. It makes a prediction about the size of the proton and its shape. Since the mass and speeds of the ``up'' and ``dn'' quark are calculated in this model, it allows a cross check of the theory. Determining the relativistic de Broglie wavelength of the up quark in the proton, it turns out that the de Broglie wavelength turns out to be less than 1{\%} different than the calculated circumference of the proton (using the magnetic moment\textellipsis ). By iterating one sees that the equations hit a natural maximum at exactly a radius of 0.519406 fm. While this number disagrees with the two disputed sizes of the proton, one will note that a value of 0.5 fm falls at about the 50{\%} point of the proton's charge distribution. Also the size of the neutron (using CBM) of 0.607939 fm is consistent with the negative dip in the charge distribution of the neutron at about 0.6 fm. It is understood that this theory disagrees with some currently held beliefs: 1. There are only 3 generations of quarks and leptons. 2. The new generation mass of the ``up'' and ``dn'' are much heavier than the u and d quarks which are in the lightest generation. 3. The mass of the top quark. This presentation will describe this theory in more detail. [Preview Abstract] |
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T01.00056: A Revision to the IRC Model of Nuclear Structure Aran Stubbs The original IRC model used a least surface method of finding best fit for an A value using BCC structures of monoquarks and diquarks, resulting in Octahedra. For small nuclei this gave a satisfactory range of Z values. For A\textgreater 180 the resultant Zs were too low. Rather than considering the structure as a unit, a better result comes from viewing the structure as a set of parallel diamond shaped sheets small to large to small, whose edge approaches circular. These sheets can be even (with a 2/2 center) or odd (with a 1/1). Nuclei can have even or odd numbers of even sheets, but only even numbers of odd sheets, to preserve parity. For sheets with an edge of 4 or above, the revised model gives additional surface that improves the A/Z ratio to include the known isotopes. [Preview Abstract] |
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T01.00057: Investigating Intrinsically Localized Vibrations in crystalline lattices using van-Hove singularities. Benjamin Agyare, Peter Riseborough Sodium Iodide has a rock salt structure. Intrinsically Localized Modes (ILMs) have supposedly been observed in NaI but only for wave-vectors at the corner of the 3-D Brillouin Zone. It has been suggested that, for high-symmetry q vectors, several van Hove singularities may converge at one critical energy producing a large peak in the two-phonon density of state spectrum and giving rise to ILMs with these q values. First, we fit the experimentally determined acoustic and the optic phonon modes using a nearest neighbor and a next-nearest neighbor force constants. We find that the two-phonon density of states, for fixed q exhibits non-divergent van Hove singularities. The energies of these features vary as q is varied and we have identified the q values at which the two-phonon density of states is enhanced. We intend to introduce anharmonic interactions and examine if it can bind the two-phonon excitations to produce a quantized ILM. [Preview Abstract] |
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T01.00058: Separating Heat and Cold by a Magnetic Body Force and the Principle for a Non-Carnot Engine Weili Luo, Jun Huang, Tianshu Liu A new type of heat engine has been proposed in 2005: A specifically designed magnetic body force can reverse heat flow from high temperature to low temperature [1]. This mechanism can drive heat to higher temperature, rendering the possibility to re-use the “waste heat”. As the result, the efficiency is much higher than that of the Carnot Engine. In a recent paper [2] a realization of this proposed mechanism is reported: by using a specific configuration of temperature and magnetic field gradients, we observed that magnetic body force suppresses the gravito-thermal convective heat when the gradients of temperature and field are anti-parallel to each other. This driving force stops the heat flow of approaching to thermal equilibrium in the system, causing the temperature difference across the sample to increase with applied fields. In this work, we will discuss the physics for the driving mechanism, the experimental results verifying the principle, its applications in energy and other industries [3], and its implication for fundamental thermodynamics law that is intimately related to the Carnot principle. \\ References: [1] Weili Luo, US Patent: WO 2007002127 A3 [2] Jun Huang, Weili Luo, and Tianshu Liu, (http://arxiv.org/abs/1611.00385) [3] Weili Luo et al. Patent pending. [Preview Abstract] |
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T01.00059: High Temperature Optimized W-HfO$_{2}$ Thermal Emitters for Thermophotovoltaic Applications Gerardo Silva, Patrick Fay, Carlos Jerez Thermophotovoltaic cells are a promising way to efficiently convert thermal radiation, e.g. from waste heat or other source, into electricity. To improve efficiency, use of ``selective emitters" that reshape the emitted electromagnetic spectrum are an attractive option. We explore the incorporation of hafnia (HfO$_{2}$) layers into two easy-to-fabricate tungsten (W) structures via rigorous coupled wave analysis. HfO$_{2}$ and W are well-suited to high temperature operation, and the high permittivity of HfO$_{2}$ enhance performance. The emittance is analyzed for metal-insulator-metal multilayer structures and one-dimensional gratings. By using a genetic algorithm with a suitable cost function and constraints, optimum geometrical parameters are found. We show that these structures exhibit very high thermal emittance, reaching normal in-band emittances higher than 90\% for both cases, with weak dependence on incidence angle. Explanations of the emittance enhancement are given through simulations using the finite element method and by theoretical considerations. The proposed emitters are designed for a working temperature of approximately 1700 K, as needed for GaSb (0.72 eV) or InGaAs (0.74 eV) photovoltaic cells. [Preview Abstract] |
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T01.00060: Role of Diffusion Induced Coalescence on Growth of Breath Figures Nilesh D. Pawar, Ramachandra D. Narhe, Sasidhar Kondaraju Growth of breath figure (the pattern formed due to condensation of water
droplets on a cold surface) have been studied using experimentally and
computer simulations. We studied the role of diffusion induced coalescence
of droplet growth. We observed that for droplet growth without diffusion
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T01.00061: Phase Studies of Model Biomembranes Jigesh Patel The effects of adding 2 mol{\%} of nACHRs to DOPC/DSPC/cholesterol lipid bilayer are studied in this experiment. To the best of our knowledge, previously, no 4-component phase diagram, with protein such as nACHRs as one of the components, has been reported. This work is the first study of this kind which investigates the effect of ion-transmitter nACHRs on L$_{\mathrm{o}}+$L$_{\mathrm{d}}$ phase boundaries. The work will also construct tie-lines and calculate various thermodynamic variable. The phase boundary will be used to calculate the chemical potential and partition coefficients. These values will determine the exact amount of nACHRs present in the cell membranes. Measurements of the perturbations of the boundaries of this accurate phase diagram could serve as a means to understand the behaviors of a range of added lipids and proteins. [Preview Abstract] |
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T01.00062: A Bioengineered Memory Device using Bacteriorhodopsin and Graphene. Roma Patel, Amanda Petrus, Isaac Macwan Bacteriorhodopsin (BR) is a photoactive protein, which has been studied as a memory storage device owing to its photochemical and thermal stability. BR photocycle comprises of two distinct stable binary states, bR (0) and Q (1) based on the wavelength of the applied radiation. However, such devices have a limited success due to low quantum yield of the Q state. Many studies have used genetic and chemical modification as optimization strategies to increase the yield of the Q state compromising the overall photochemical stability. Here we come up with a unique way of stabilizing this BR and Q states through its adsorption onto graphene. We have used all-atom molecular dynamics (MD) simulations utilizing NAMD and the CHARMM force field to understand the interactive events at the interface of BR and a single layer graphene sheet. Based on the stable RMSD and interactive energies such as van der Waals and electrostatics, we propose that the adsorption of BR onto graphene can stabilize the photochemical behavior of BR. Furthermore, the switching between Cis and Trans conformations of the retinal based on the angular change of the dihedral demonstrates that such an adsorption is beneficial to preserve the binary states. [Preview Abstract] |
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T01.00063: Molecular Interactions Between Mismatch Repair Protein MutS and DNA from the Perspective of Colorectal Cancer. Sanjay Karimbanamlayil Babu, Kavya Chandrika Hemmanur, Isaac Macwan, Prabir Patra It is estimated that about 30{\%} of the colorectal cancer (CRC) cases are hereditary and related to known syndromes, particularly Lynch Syndrome. This study aims to understand the molecular interactions between a mismatch repair protein, MutS and a mismatched DNA through a DNA-graphene-polypyrole (DGP) biosensor and molecular dynamics. Electrochemical impedance spectroscopy (EIS) analysis of the DGP biosensor confirms the adsorption of the DNA probe and its interactions with MutS. These results are supported by a set of all-atom molecular dynamics simulations using NAMD and CHARMM force fields. Within the first 200ns of the molecular interactions between MutS and mismatched DNA, we portray the conformational changes of the human MutS protein as it binds to the DNA. It is further found that within the first 50ns, the reactive site on the MutS protein (residues 1 to 124) start to favorably interact with the DNA for the onset of the scan cycle. This investigation additionally provides crucial insights into the interactive energetic events at the interface of MutS and the DNA through non-binding energies, thereby mapping out the events during scanning and locating the mismatch. [Preview Abstract] |
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T01.00064: Dark-Sectors: Matter(DM) Roots-of-Unity(ROU)/Energy(DE) Automatic in “PRE”-(r,t<0) Cosmo-GONY-BECOME-OLOGY Zohar-Heschel-Shapiro-Siegel(ZHSS) SEPHIROT Mathematical-Universe Hypothesis-BECOME-SCENARIO(SMUHBS) J Zohar, Abraham Herschel, Edward Carl-Ludwig Siegel, Simon Newcomb, Marvin Antonoff Siegel [Schrodinger Centenary Symp.(87); Symp Fdns.Mod. Phys.(87)] DM Ruben/Ford(77) DM ROU- “complex quantum-statistics in fractal-dimensions” via Tagakagi-Oguri generic quantum-statistics via pure-mathematics Euler-formula/deMovrie-formula ROU expansion Kramers-Kronig dispersion-relations complex-damping denominator, part of ZHSS SMUHBS. Newcomb(1881)[benfordonline.net/list/chronological] Digits[0-9] STATISTICS LOG-LAW Siegel/Antonoff[Joint-Maths.Mtg.(02)] algebraic-inversion involution to ONLY BOSONS: {DIGITS}=BOSONS: AUTOMATIC BIG-BANG(“let there be light”):inflation from log-exp- mirror symmetry; Boson Taylor-expansion to CMB. Mellin-transform CONICS-interchange to SUSY. DE ever-accelerating boundaryLESS universe summary “world WITHOUT end” implying 4-D Hopf-fibration boundary-folding back-to any/all (3+1)-spacetime 4-localities local internal pressure of Einstein cosmological-constant! [Preview Abstract] |
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T01.00065: Study of Maris polarization in neutron rich nuclei FNU Shubhchintak, Carlos A. Bertulani, T. Aumann In quasi-free (p, 2p) reactions, which are the powerful tool to study the nuclear spectroscopy, the Maris polarization can be defined as the difference in polarization of the ejected proton when it is ejected from $j = l+s$ or from $j= l-s$ orbital. In fact, this results from the combined affects of absorption, the spin-orbit part of the optical potential and the spin-dependence of the nucleon nucleon interactions. We will present a theoretical study of the Maris polarization effect in neutron rich nuclei in order to assess the information on the structure of exotic nuclei. In particular, we will explore the dependence of the polarization effect on neutron excess and neutron-skin thickness. We will also discuss the uncertainties in the calculations due to the various NN interactions and optical potentials. [Preview Abstract] |
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T01.00066: Discovering strong-field quantum physics using the CoReLS 4 PW laser Bjoern Manuel Hegelich, Hyung Taek Kim, Lance Labun, Ou Zhang Labun, Seong Ku Lee, Chang Hee Nam At the Center for Relativistic Laser Science we have commissioned the world’s most intense laser, with a 4 PW and 1.5 PW beam. It has demonstrated an intensity of I>$10^{23} W/cm^2, the highest intensity to date. At those intensities any interaction with matter involves physics at many length and momentum scales and a combination of classical and quantum dynamics is needed to describe it. Single electrons in the plasma are quickly accelerated to energies much greater than their mass must be treated in quantum electrodynamics (QED). The collective plasma dynamics, which govern the initial conditions of the interaction, do not resolve the electron Compton wavelength and have to be treated as classical. To describe such a broad range of scales, we derive from QED a new effective quantum field theory that systematically separates the classical and quantum physics. With this tool providing systematic predictions, we can search for the uniquely strong-field effects that motivate fundamental research with high-intensity lasers. We plan to experimentally validate the theory as the first laboratory probe of quantum effects in strong classical potentials observing recoil from intense classical radiation and by exploring spontaneous pair production in nonlinear Compton scattering. [Preview Abstract] |
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T01.00067: The Effects of Summer Camp on Participants' Affective Views of Science Iliana De La Cruz, Micha Kilburn There exists a movement to draw more diverse groups of students to science, technology, engineering, and math (STEM) careers. While limited research on the effect of informal education on K-12 students’ views of science exists, recent data suggests children decide for or against STEM as early as grade school. This research quantitatively examines the effect a STEAM summer camp had on its participants’ affective views of science. Using pre-post surveys, the participants were asked to rate their interest in science, list career aspirations, and associate words they thought describe science or art. Researchers analyzed four years of these programmatic surveys for correlations between words associated with science, and age or gender. This summer, researchers also interviewed camp participants to better understand the reasoning behind word associations and to evaluate the survey instrument. Preliminary statistical analysis suggests camp affects participant word associations. Interview results highlighted points of confusion in participant survey instruction interpretation leading researchers to continue examining the survey instrument. [Preview Abstract] |
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T01.00068: Bypassing formal Lagrangians and modifying Les Houches files by hand Myrl Smith, Matthew Bellis When an experimentalist wants to search for a new physics process at a collider the first order of business is to generate Monte Carlo events at the quark-level. Following that, the hadronization of the quarks is simulated through PYTHIA, the detector response is simulated using GEANT, and the reconstruction efficiency is estimated. While the second step can be computationally very time consuming, the bottleneck is often generating the raw events at quark-level if the physics is brand new. The tool of choice is MadGraph, which allows the user to define the rules of their Lagrangian, but an analyst has to find a theorist who will to code this up. We have used MadGraph to generate the most basic of processes and then simulated subsequent decays through a phenomenological model and then added this properly to the output Les Houches files. We present the status of this proof-of-concept approach and suggest ways that this could be used to test other models after the fact. [Preview Abstract] |
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T01.00069: Application of Physical and Mathematical Transformations in Analyzing Sound Spectrum and Frequency of the Cello Bumjoon Choi, Richard Kyung The original frequencies of a sound are reduced and represented in a sound spectrum, using dB or Pascal. This sound spectrum characterizes not only the frequencies in sound but also the amount of energy in a frequency band. This paper examines the sound spectrum of musical instruments, such as Cello. The sound wave created by instruments are transformed from time domain to frequency domain. Through studying the sound spectrum, this research analyzes vibrational characteristics and compares such characteristics across several musical instruments. The computational experiment, including the vibrational analysis, is completed with sample sound files using a computer program. The sound spectrum plot of the instrument Cello is created and analyzed to discover the function of the plot. Then, a script for generating spectra plots for any instrument can be generated. When examining the sound spectrum for string instruments, strong peaks at the first and third harmonic components are present. When comparing the sound of the cello and violin, the cello produces a more pure tone and the violin produces a more fuzzy tone. Wood instruments, on the contrary, show strong peaks at the second and/or third harmonic components, rather than the first harmonic component. [Preview Abstract] |
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T01.00070: A Study on Statistical Simulation for Modeling and Forecasting Sports Economics Jae Yoon Cho, Dong Ho Choi In light of the increasing popularity of collegiate and professional athletics, the study of sports economics has expanded rapidly in recent years. This research utilizes recent theoretical advances in Economics and shows how economic theories can be implemented to solve complex tasks of forecasting and valuing sports businesses. In this paper, statistical and simulation models are used for valuation of sports business and also for predicting and evaluating markets and forecasting and measuring the impact of regulatory measures. To describe the business Economics, the Matlab program is employed to ascertain an overview of sophisticated sports businesses; by importing data directly from databases, the efficacy of financial applications are reviewed. This process of studying the sports business data enables us to analyze the data management, perform predictions, and carry out more relevant additional diagnostic tests. [Preview Abstract] |
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T01.00071: Neutron Distributions Surrounding a Medical Linear Accelerator Allen Alfadhel, Paul Johnson, Jack Thomas, Molly McDonough, Erick Bergstrom, Jackson Nolan, Mario Rojas, Dr. Walter Johnson, Dr. Jacqueline Nyamwanda Bubble neutron detectors and high purity metal foils were used for determining the neutron distribution in the space surrounding a medical linear accelerator (LINAC). The neutron fluence at some point depends on the direct radiation from the head with its inverse distance squared dependence and another term due to the low energy scattered and thermal neutrons. The bubble detectors provide information in the 200 Kev to 15 MEV range and neutron activation of the metal foils provides information in the 0.25 eV to 250 keV range. The neutron fluence equation with Q dependence on the inverse squared term and also on the low energy neutrons provides a means of determining Q for the machine. [Preview Abstract] |
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T01.00072: Abstract Withdrawn
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T01.00073: An inexpensive networked cosmic-ray detector Samuel Schaub, Kripa George, Michael McCracken The desktop muon detector designed by Axani et al. combines silicon photomultiplier (SiPM) scintillator readout and relatively inexpensive electronics into a comprehensive hardware project suitable for undergraduates or citizen scientists. We present a modification of the detector design that adds wifi connectivity using an ESP8266 module, allowing the detector to upload event information to a central server for later analysis. This connected design allows for distributed data collection and pooling of data from an arbitrary number of detectors. We demonstrate some of the basic tools for analyzing this data. This work is aimed at furthering physics outreach by building a global web of inexpensive cosmic ray detectors and a community of collaborative data analysis. [Preview Abstract] |
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