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Elasticity Of Cylindrical Black Holes, Conrad Pearson 2016 California Polytechnic State University, San Luis Obispo

Elasticity Of Cylindrical Black Holes, Conrad Pearson

Physics

Black holes are regions of strong gravity, and are often regarded as behaving like drops of fluid. When this line of thought is applied to cylindrical black holes (black cylinders), a mapping can be made between known instabilities for black cylinders and ordinary fluid cylinders. However, this known correlation is increasingly less accurate for lower spatial dimensions, and I seek to correct this discrepancy in this thesis. By considering soft solids instead of pure fluids, elastic energy can be included, which brings us closer to a direct comparison. In improving this mapping, it becomes possible to better understand the behavior ...


Photonic Crystals With Alternate Arrays Of Rods And Holes In A Low Dielectric-Index Material, Dimitar L. Dimitrov 2016 Graduate Center, City University of New York

Photonic Crystals With Alternate Arrays Of Rods And Holes In A Low Dielectric-Index Material, Dimitar L. Dimitrov

All Graduate Works by Year: Dissertations, Theses, and Capstone Projects

This thesis theoretically deals with the propagation of electromagnetic waves (light beams) in periodically modulated dielectric material structures based on Maxwell’s equations. We are interested in novel light propagation characteristics in these man-made dielectric material structures for practical applications, especially on optical communications and computations. Since the wavelength range of light is on the same order of magnitude as the modulation periods of dielectric materials, an analogy of the light propagation in dielectric-constant modulated structures with the electron transport in solid-state crystals is used throughout my thesis by using a term “photonic crystals (PhCs)” referring to these dielectric structures ...


Transmission Of Focused Picosecond Light Pulse Through Multimode Fibers, Yin Cen 2016 The Graduate Center, City University of New York

Transmission Of Focused Picosecond Light Pulse Through Multimode Fibers, Yin Cen

All Graduate Works by Year: Dissertations, Theses, and Capstone Projects

This thesis focuses on a technique of delivering spatially focused and temporally compressed picosecond laser pulses through multimode fibers. This study was inspired by recent success in focusing light through optically diffusive media of which multimode fibers were a special case in terms of causing scrambled phase distribution in the transmitted light. The approach involved controlling the phase distribution of incoming beam using a deformable mirror prior to its entry into the multimode fiber in order to achieve constructive interference at selected spots in the output. With phase control, the intensity of the focused light at the output can be ...


Some 2-Categorical Aspects In Physics, Arthur Parzygnat 2016 The Graduate Center, City University of New York

Some 2-Categorical Aspects In Physics, Arthur Parzygnat

All Graduate Works by Year: Dissertations, Theses, and Capstone Projects

2-categories provide a useful transition point between ordinary category theory and infinity-category theory where one can perform concrete computations for applications in physics and at the same time provide rigorous formalism for mathematical structures appearing in physics. We survey three such broad instances. First, we describe two-dimensional algebra as a means of constructing non-abelian parallel transport along surfaces which can be used to describe strings charged under non-abelian gauge groups in string theory. Second, we formalize the notion of convex and cone categories, provide a preliminary categorical definition of entropy, and exhibit several examples. Thirdly, we provide a universal description ...


Nucleon Decay, Atmospheric Neutrinos, And Cosmic Rays At Dune: September 2016 Progress Report, E. Church, D. Dwyer, H. Gallagher, M. Goodman, R. Hatcher, J. Hewes, A. Higuera, V. A. Kudryavtsev, L. Lin, N. Martinez, H. Méndez, J. L. Raaf, M. Robinson, G. Santucci, M. Sorel, A. Tonazzo, T. K. Warburton, K. Wood, T. Yang 2016 Northwest National Laboratory,

Nucleon Decay, Atmospheric Neutrinos, And Cosmic Rays At Dune: September 2016 Progress Report, E. Church, D. Dwyer, H. Gallagher, M. Goodman, R. Hatcher, J. Hewes, A. Higuera, V. A. Kudryavtsev, L. Lin, N. Martinez, H. Méndez, J. L. Raaf, M. Robinson, G. Santucci, M. Sorel, A. Tonazzo, T. K. Warburton, K. Wood, T. Yang

Progress Reports

We report on the progress made within the Nucleon Decay, Atmospheric Neutrinos, and Cosmogenics Physics Working Groups since the DUNE CDR, and in particular in the period September 2015 { September 2016. This note is also intended to provide input for the September 2016 Preliminary Report of the Far Detector Task Force. We report jointly for the three WGs since they are tightly coupled. They make use of the same DUNE Far Detector for their physics studies, they share the same energy regime, and they are all characterized by random, non-beam triggers. Finally, cosmogenic events are a background for atmospheric neutrino ...


Discrete Symmetries And Isosinglet Quarks In Low-Energy Supersymmetry, Diego Castano, Stephan P. Martin 2016 Massachusetts Institute of Technology

Discrete Symmetries And Isosinglet Quarks In Low-Energy Supersymmetry, Diego Castano, Stephan P. Martin

Diego Castano

Many extensions of the minimal supersymmetric standard model contain superfields for quarks which are singlets under weak isospin with electric charge . We explore the possibility that such isosinglet quarks have low or intermediate scale masses, but do not mediate rapid proton decay because of a discrete symmetry. By imposing the discrete gauge anomaly cancellation conditions, we show that the simplest way to achieve this is to extend the Z3 “baryon parity” of Ibáñez and Ross to the isosinglet quark superfields. This can be done in three distinct ways. This strategy is not consistent with grand unification with a simple ...


Mass And Mixing-Angle Patterns In The Standard Model And Its Minimal Supersymmetric Extension, H. Arason, Diego Castano, E. J. Piard, P. Ramond 2016 University of Florida

Mass And Mixing-Angle Patterns In The Standard Model And Its Minimal Supersymmetric Extension, H. Arason, Diego Castano, E. J. Piard, P. Ramond

Diego Castano

Using renormalization group techniques, we examine several interesting relations among masses and mixing angles of quarks and leptons in the standard model. We extend the analysis to the minimal supersymmetric extension to determine its effect on these mass relations. Remarkably supersymmetry allows for these relations to be satisfied at a single grand unified scale.


Naturalness And Superpartner Masses Or When To Give Up On Weak Scale Supersymmetry, Greg W. Anderson, Diego Castano 2016 Massachusetts Institute of Technology

Naturalness And Superpartner Masses Or When To Give Up On Weak Scale Supersymmetry, Greg W. Anderson, Diego Castano

Diego Castano

Superpartner masses cannot be arbitrarily heavy if supersymmetric extensions of the standard model explain the stability of the gauge hierarchy. This ancient and hallowed motivation for weak scale supersymmetry is often quoted, yet no reliable determination of this upper limit on superpartner masses exists. In this paper we compute upper bounds on superpartner masses in the minimal supersymmetric model, and we identify which values of the superpartner masses correspond to the most natural explanation of the hierarchy stability. We compare the most natural value of these masses and their upper limits to the physics reach of current and future colliders ...


Consequences Of Supergravity With Gauged U(1)R Symmetry, Diego Castano, D. Z. Freedman, C. Manuel 2016 Massachusetts Institute of Technology

Consequences Of Supergravity With Gauged U(1)R Symmetry, Diego Castano, D. Z. Freedman, C. Manuel

Diego Castano

The structure of gauged R-supergravity Lagrangians is reviewed, and we consider models with a hidden sector plus light fields of the MSSM. A simple potential for the hidden sector is presented which has a global minimum with zero cosmological constant and spontaneously broken SUSY and R-symmetry. The U(1)R vector multiplet acquires a Planck scale through the Higgs mechanism, and it decouples at low energy. Due to very interesting cancellations, the U(1)RD-terms also drop out at low energy. Thus no direct effects of the gauging of R-symmetry remain in the low-energy effective ...


Naturalness Lowers The Upper Bound On The Lightest Higgs Boson Mass In Supersymmetry, Greg W. Anderson, Diego Castano, Antonio Riotto 2016 Fermi National Accelerator Laboratory

Naturalness Lowers The Upper Bound On The Lightest Higgs Boson Mass In Supersymmetry, Greg W. Anderson, Diego Castano, Antonio Riotto

Diego Castano

We quantify the extent to which naturalness is lost as experimental lower bounds on the Higgs boson mass increase, and we compute the natural upper bound on the lightest supersymmetric Higgs boson mass. We find that it would be unnatural for the mass of the lightest supersymmetric Higgs boson to saturate its maximal upper bound. In the absence of significant fine-tuning, the lightest Higgs boson mass should lie below 120 GeV, and in the most natural cases it should be lighter than 108 GeV. For modest tanβ, these bounds are significantly lower. Our results imply that a failure to observe ...


Measure Of Fine Tuning, Greg W. Anderson, Diego Castano 2016 Massachusetts Institute of Technology

Measure Of Fine Tuning, Greg W. Anderson, Diego Castano

Diego Castano

Fine-tuning criteria are frequently used to place upper limits on the masses of superpartners in supersymmetric extensions of the standard model. However, commonly used prescriptions for quantifying naturalness have some important shortcomings. Motivated by this, we propose new criteria for quantifying fine tuning that can be used to place upper limits on superpartner masses with greater fidelity. In addition, our analysis attempts to make explicit the assumptions implicit in quantifications of naturalness. We apply our criteria to the minimal supersymmetric extension of the standard model, and we find that the scale of supersymmetry breaking can be larger than previous methods ...


Renormalization Group Study Of The Standard Model And Its Extensions: The Minimal Supersymmetric Standard Model, Diego Castano, E. J. Piard, P. Raymond 2016 Massachusetts Institute of Technology

Renormalization Group Study Of The Standard Model And Its Extensions: The Minimal Supersymmetric Standard Model, Diego Castano, E. J. Piard, P. Raymond

Diego Castano

In this paper we summarize the minimal supersymmetric standard model as well as the renormalization group equations of its parameters. We proceed to examine the feasibility of the model when the breaking of supersymmetry is parametrized by the soft terms suggested by supergravity theories. In such models, the electroweak symmetry is exact at the tree level and is broken spontaneously at one-loop order. We make the additional assumption that the GUT-inspired relation mb=mτ be valid at the scale where the gauge coupling constants unify, which constrains the value of the top quark mass. For all types of soft breaking ...


Renormalization-Group Study Of The Standard Model And Its Extensions: The Standard Model, H. Arason, Diego Castano, B. Kesthelyi, S. Mikaelian, E. J. Piard, P. Ramond, B. D. Wright 2016 University of Florida

Renormalization-Group Study Of The Standard Model And Its Extensions: The Standard Model, H. Arason, Diego Castano, B. Kesthelyi, S. Mikaelian, E. J. Piard, P. Ramond, B. D. Wright

Diego Castano

In this paper we present a comprehensive analysis of the running of all the couplings of the standard model to two loops, including threshold effects. Our purpose is twofold—to determine what the running of these parameters may indicate for the physics of the standard model and to provide a template for the study of its extensions up to the Planck mass.


B⃗ Sγ Constraints On The Minimal Supergravity Model With Large Tanβ, Howard Baer, Michal Brhlik, Diego Castano, Xerxes Tata 2016 Florida State University

B⃗ Sγ Constraints On The Minimal Supergravity Model With Large Tanβ, Howard Baer, Michal Brhlik, Diego Castano, Xerxes Tata

Diego Castano

In the minimal supergravity model (MSUGRA), as the parameter tanβ increases, the charged Higgs boson and light bottom squark masses decrease, which can potentially increase contributions from tH±, g̃bj and Zibj loops in the decay b⃗ sγ. We update a previous QCD improved b⃗ sγ decay calculation to include in addition the effects of gluino and neutralino loops. We find that, in the MSUGRA model, loops involving charginos also increase, and dominate over tW, tH±, g̃q̃ and Ziq̃contributions for tanβ≳5−10. We find for large values of tanβ∼35 that most of the parameter space of ...


Challengin Weak-Scale Supersymmetry At Colliders, Greg W. Anderson, Diego Castano 2016 Massachusetts Institute of Technology

Challengin Weak-Scale Supersymmetry At Colliders, Greg W. Anderson, Diego Castano

Diego Castano

Experimental searches for supersymmetry are entering a new era. As future experiments explore the mass range above the current lower bounds on superpartner masses, a failure to observe signals of superpartner production will begin to erode the central motivation for supersymmetry at the weak scale. In this article we present a detailed examination of which regions of supersymmetric parameter space are most natural and the extent to which weak-scale supersymmetry becomes unnatural if no superpartners are observed at CERN LEP II, the Fermilab Tevatron, possible upgrades of these machines, and the CERN LHC.


Multiferroic Pb(Fe1/2Nb1/2)O3 Single Crystals: A Raman Scattering Study, A. F. García-Flores, Dmitri A. Tenne, W. J. Ren, X. X. Xi., S. -W. Cheong 2016 Pennsylvania State University

Multiferroic Pb(Fe1/2Nb1/2)O3 Single Crystals: A Raman Scattering Study, A. F. García-Flores, Dmitri A. Tenne, W. J. Ren, X. X. Xi., S. -W. Cheong

Dmitri Tenne

No abstract provided.


Adsorption-Controlled Growth Of Bivo4 By Molecular-Beam Epitaxy, D. A. Hillsberry, D. A. Tenne 2016 Boise State University

Adsorption-Controlled Growth Of Bivo4 By Molecular-Beam Epitaxy, D. A. Hillsberry, D. A. Tenne

Dmitri Tenne

Single-phase epitaxial films of the monoclinic polymorph of BiVO4 were synthesized by reactive molecular-beam epitaxy under adsorption-controlled conditions. The BiVO4 films were grown on (001) yttria-stabilized cubic zirconia (YSZ) substrates. Four-circle x-ray diffraction, scanning transmission electron microscopy (STEM), and Raman spectroscopy confirm the epitaxial growth of monoclinic BiVO4 with an atomically abrupt interface and orientation relationship (001)BiVO4 ∥ (001)YSZ with [100]BiVO4 ∥ [100]YSZ. Spectroscopic ellipsometry, STEM electron energy loss spectroscopy (STEM-EELS), and x-ray absorption spectroscopy indicate that the films have a direct band gap of 2.5 ± 0.1 eV.


High-Flux Femtosecond X-Ray Emission From Controlled Generation Of Annular Electron Beams In A Laser Wakefield Accelerator, T. Z. Zhao, K. Behm, C. F. Dong, X. Davoine, Serge Y. Kalmykov, V. Petrov, Vladimir Chvykov, P. Cummings, B. Hou, Anatoly Maksimchuk, J. A. Nees, Victor Yanovsky, A. G. R. Thomas, Karl Krushelnick 2016 Center for Ultrafast Optical Science, University of Michigan, Ann Arbor, MI 48109

High-Flux Femtosecond X-Ray Emission From Controlled Generation Of Annular Electron Beams In A Laser Wakefield Accelerator, T. Z. Zhao, K. Behm, C. F. Dong, X. Davoine, Serge Y. Kalmykov, V. Petrov, Vladimir Chvykov, P. Cummings, B. Hou, Anatoly Maksimchuk, J. A. Nees, Victor Yanovsky, A. G. R. Thomas, Karl Krushelnick

Serge Youri Kalmykov

Annular quasimonoenergetic electron beams with a mean energy in the range 200–400 MeV and charge on the order of several picocoulombs were generated in a laser wakefield accelerator and subsequently accelerated using a plasma afterburner in a two-stage gas cell. Generation of these beams is associated with injection occurring on the density down ramp between the stages. This well-localized injection produces a bunch of electrons performing coherent betatron oscillations in the wakefield, resulting in a significant increase in the x-ray yield. Annular electron distributions are detected in 40% of shots under optimal conditions. Simultaneous control of the pulse duration ...


Alamethicin In Lipid Bilayers: Combined Use Of X-Ray Scattering And Md Simulations, Jianjun Pan, D. Peter Tieleman, John F. Nagle, Norbert Kučerka, Prof. Stephanie Tristram-Nagle Ph.D. 2016 Carnegie Mellon University

Alamethicin In Lipid Bilayers: Combined Use Of X-Ray Scattering And Md Simulations, Jianjun Pan, D. Peter Tieleman, John F. Nagle, Norbert Kučerka, Prof. Stephanie Tristram-Nagle Ph.D.

John Copeland Nagle

We study fully hydrated bilayers of two di-monounsaturated phospholipids diC18:1PC (DOPC) and diC22:1PC with varying amounts of alamethicin (Alm). We combine the use of X-ray diffuse scattering and molecular dynamics simulations to determine the orientation of alamethicin in model lipids. Comparison of the experimental and simulated form factors shows that Alm helices are inserted transmembrane at high humidity and high concentrations, in agreement with earlier results. The X-ray scattering data and the MD simulations agree that membrane thickness changes very little up to 1/10 Alm/ DOPC. In contrast, the X-ray data indicate that the thicker diC22:1PC ...


Ultraviolet Lasing In High-Order Bands Of Three-Dimensional Zno Photonic Crystals, Michael Scharrer, Alexey Yamilov, Xiaohua Wu, Hui Cao, Robert P. H. Chang 2016 Missouri University of Science and Technology

Ultraviolet Lasing In High-Order Bands Of Three-Dimensional Zno Photonic Crystals, Michael Scharrer, Alexey Yamilov, Xiaohua Wu, Hui Cao, Robert P. H. Chang

Alexey Yamilov

UV lasing in three-dimensional ZnO photonic crystals is demonstrated at room temperature. The photonic crystals are inverse opals with high refractive index contrast that simultaneously confine light and provide optical gain. Highly directional lasing with tunable wavelength is obtained by optical pumping. Comparison of the experimental results to the calculated band structure shows that lasing occurs in high-order bands with abnormally low group velocity. This demonstrates that the high-order band structure of three-dimensional photonic crystals can be used to effectively confine light and enhance emission. Our findings may also impact other applications of photonic crystal devices. ©2006 American Institute of ...


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