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Articles 18001 - 18030 of 34975

Full-Text Articles in Physics

Search For The Standard Model Higgs Boson In The H → Zz → ℓ+ℓ−Τ+Τ− Decay Channel In Pp Collisions At S√=7tev, The Cms Collaboration, S. Chatrchyan, V. Khachatryan, Marc M. Baarmand, B. Dorney, Marcus Hohlmann, Himali Kalakhety, Igor Vodopiyanov Jan 2012

Search For The Standard Model Higgs Boson In The H → Zz → ℓ+ℓ−Τ+Τ− Decay Channel In Pp Collisions At S√=7tev, The Cms Collaboration, S. Chatrchyan, V. Khachatryan, Marc M. Baarmand, B. Dorney, Marcus Hohlmann, Himali Kalakhety, Igor Vodopiyanov

Aerospace, Physics, and Space Science Faculty Publications

A search is reported for the standard model Higgs boson in the H → ZZ → ℓ+ℓ−τ +τ − decay mode, where ℓ = μ or e, in proton-proton collisions at s=7TeV" role="presentation" style="box-sizing: inherit; display: inline; line-height: normal; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">s√=7TeV�=7TeV, corresponding to an integrated luminosity of 4.7 fb−1 collected with the CMS detector at the LHC. No evidence is found for a significant deviation from the background expectation. …

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Measurement Of The Top-Quark Mass In Tt¯ Events With Lepton+Jets Final States In Pp Collisions At S√=7 Tev, The Cms Collaboration, S. Chatrchyan, V. Khachatryan, Marc M. Baarmand, B. Dorney, Marcus Hohlmann, Himali Kalakhety, Igor Vodopiyanov Jan 2012

Measurement Of The Top-Quark Mass In Tt¯ Events With Lepton+Jets Final States In Pp Collisions At S√=7 Tev, The Cms Collaboration, S. Chatrchyan, V. Khachatryan, Marc M. Baarmand, B. Dorney, Marcus Hohlmann, Himali Kalakhety, Igor Vodopiyanov

Aerospace, Physics, and Space Science Faculty Publications

The mass of the top quark is measured using a sample of tt candidate events with one electron or muon and at least four jets in the nal state, collected by CMS in pp collisions at p s = 7TeV at the LHC. A total of 5174 candidate events is selected from data corresponding to an integrated luminosity of 5.0 fb􀀀1. For each event the mass is reconstructed from a kinematic t of the decay products to a tt hypothesis. The topquark mass is determined simultaneously with the jet energy scale (JES), constrained by the known mass of the W …

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Hybrid Organic/Quantum Dot Photovoltaics, Timothy Paul Osedach Jan 2012

Hybrid Organic/Quantum Dot Photovoltaics, Timothy Paul Osedach

Link Foundation Energy Fellowship Reports

The aim of the work conducted during this tenure as a Link Foundation Energy Fellow was to investigate the fundamental excitonic and charge transport process that are relevant in nanostructured photovoltaics structures, and to demonstrate photovoltaics structures that incorporate novel nanostructured materials toward realizing high efficiency and low cost solar cells.

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Optically Trapped Fluorescent Nanodiamonds, Viva Horowitz Jan 2012

Optically Trapped Fluorescent Nanodiamonds, Viva Horowitz

Scholarly Projects

The nitrogen-vacancy (NV) color center in diamond is gaining significant interest for applications in nanoscale sensing. The optical addressability of the magnetically sensitive spin states and the ability to coherently control these states at room temperature makes this system an exciting candidate for spin-based magnetometry. I constructed an optical tweezers apparatus combined with a confocal fluorescence apparatus. Using the optical apparatus, we demonstrate three-dimensional position control of nanodiamonds in solution with simultaneous readout of ground-state electron-spin resonance (ESR) transitions in an ensemble of diamond nitrogen-vacancy (NV) color centers. Despite the motion and random orientation of NV centers suspended in the …

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Dark Matter Time Projection Chamber: Recent R&D Results, James B. R. Battat, S. Ahlen, M. Chernicoff Jan 2012

Dark Matter Time Projection Chamber: Recent R&D Results, James B. R. Battat, S. Ahlen, M. Chernicoff

Physics Faculty Research and Scholarship

The Dark Matter Time Projection Chamber collaboration recently reported a dark matter limit obtained with a 10 liter time projection chamber filled with CF4 gas. The 10 liter detector was capable of 2D tracking (perpendicular to the drift direction) and 2D fiducialization, and only used information from two CCD cameras when identifying tracks and rejecting backgrounds. Since that time, the collaboration has explored the potential benefits of photomultiplier tube and electronic charge readout to achieve 3D tracking, and particle identification for background rejection. The latest results of this effort is described here.

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Methyl Group Rotation, H-1 Spin-Lattice Relaxation In An Organic Solid, And The Analysis Of Nonexponential Relaxation, Peter A. Beckmann, Evan Schneider Jan 2012

Methyl Group Rotation, H-1 Spin-Lattice Relaxation In An Organic Solid, And The Analysis Of Nonexponential Relaxation, Peter A. Beckmann, Evan Schneider

Physics Faculty Research and Scholarship

We report 1H spin-lattice relaxation measurements in polycrystalline 4,4′-dimethoxybiphenyl at temperatures between 80 and 300 K at NMR frequencies of ω0/2π = 8.50, 22.5, and 53.0 MHz. The data are interpreted in terms of the simplest possible Bloch-Wangsness-Redfield methyl group hopping model. Different solid states are observed at low temperatures. The 1H spin-lattice relaxation is nonexponential at higher temperatures where a stretched-exponential function fits the data very well, but this approach is phenomenological and not amenable to theoretical interpretation. (We provide a brief literature review of the stretched-exponential function.) The Bloch-Wangsness-Redfield model applies …

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Growth Diagram And Magnetic Properties Of Hexagonal Lufe2o4 Thin Films, Wenbin Wang, Zheng Gai, Miaofang Chi, Jason D. Fowlkes, Jieyu Yi, Leyi Zhu, Xuemei Cheng, David J. Keavney, Paul C. Snijders, Thomas Z. Ward, Jian Shen, Xiaoshan Xu Jan 2012

Growth Diagram And Magnetic Properties Of Hexagonal Lufe2o4 Thin Films, Wenbin Wang, Zheng Gai, Miaofang Chi, Jason D. Fowlkes, Jieyu Yi, Leyi Zhu, Xuemei Cheng, David J. Keavney, Paul C. Snijders, Thomas Z. Ward, Jian Shen, Xiaoshan Xu

Physics Faculty Research and Scholarship

A growth diagram of Lu-Fe-O compounds on MgO(111) substrates using pulsed laser deposition is constructed based on extensive growth experiments. The LuFe2O4 phase can only be grown in a small range of temperature and O2 pressure conditions. An understanding of the growth mechanism of Lu-Fe-O compound films is offered in terms of the thermochemistry at the surface. Superparamagnetism is observed in the LuFe2O4 film and is explained in terms of the effect of the impurity hexagonal LuFeO3 (h-LuFeO3) phase and structural defects.

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Structure And Magnetotransport Properties Of Epitaxial Nanocomposite La0.67ca0.33mno3:Srtio3 Thin Films Grown By A Chemical Solution Approach, Ling Fei, Leyi Zhu, Xuemei Cheng, Haiyan Wang, Stacy M. Baber, Joshua Hill, Qianglu Lin, Yun Xu, Shuguang Deng, Hongmei Luo Jan 2012

Structure And Magnetotransport Properties Of Epitaxial Nanocomposite La0.67ca0.33mno3:Srtio3 Thin Films Grown By A Chemical Solution Approach, Ling Fei, Leyi Zhu, Xuemei Cheng, Haiyan Wang, Stacy M. Baber, Joshua Hill, Qianglu Lin, Yun Xu, Shuguang Deng, Hongmei Luo

Physics Faculty Research and Scholarship

Epitaxial La0.67Ca0.33MnO3:SrTiO3 (LCMO:STO) composite thin films have been grown on single crystal LaAlO3(001) substrates by a cost effective polymer-assisted deposition method. Both x-ray diffraction and high-resolution transmission electron microscopy confirm the growth of epitaxial films with an epitaxial relationship between the films and the substrates as (002)film||(002)sub and [202]film||[202]sub. The transport property measurement shows that the STO phase significantly increases the resistivity and enhances the magnetoresistance (MR) effect of LCMO and moves the metal-insulator transition to lower temperatures. For example, the MR values measured …

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Crystal Field Splitting And Optical Bandgap Of Hexagonal Lufeo3 Films, Wenbin Wang, Hongwei Wang, Xiaoying Xu, Leyi Zhu, Lixin He, Elizabeth Wills, Xuemei Cheng, David J. Keavney, Jian Shen, Xifan Wu, Xiaoshan Xu Jan 2012

Crystal Field Splitting And Optical Bandgap Of Hexagonal Lufeo3 Films, Wenbin Wang, Hongwei Wang, Xiaoying Xu, Leyi Zhu, Lixin He, Elizabeth Wills, Xuemei Cheng, David J. Keavney, Jian Shen, Xifan Wu, Xiaoshan Xu

Physics Faculty Research and Scholarship

Hexagonal LuFeO3 films have been studied using x-ray absorption and optical spectroscopy. The crystal splitting of Fe3+ is extracted as Ee′−Ee″ = 0.7 eV and Ea1′−Ee′ = 0.9 eV, and a 2.0 eV optical bandgap is determined assuming a direct gap. First-principles calculations confirm the experiments that the relative energies of crystal field splitting states do follow Ea1′>Ee′>Ee″ with slightly underestimated values and a bandgap of 1.35 eV.

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Modification Of Turbulent Transport With Continuous Variation Of Flow Shear In The Large Plasma Device, David A. Schaffner, T. A. Carter, G. D. Rossi, D. S. Guice, J. E. Maggs, S. Vincena, B. Friedman Jan 2012

Modification Of Turbulent Transport With Continuous Variation Of Flow Shear In The Large Plasma Device, David A. Schaffner, T. A. Carter, G. D. Rossi, D. S. Guice, J. E. Maggs, S. Vincena, B. Friedman

Physics Faculty Research and Scholarship

Continuous control over azimuthal flow and shear in the edge of the Large Plasma Device (LAPD) has been achieved using a biasable limiter which has allowed a careful study of the effect of flow shear on pressure-gradient-driven turbulence and transport in the LAPD. The LAPD rotates spontaneously in the ion diamagnetic direction; positive limiter bias first reduces, then minimizes (producing a near-zero shear state), and finally reverses the flow into the electron diamagnetic direction. Degradation of particle confinement is observed in the minimum shearing state and a reduction in the turbulent particle flux is observed with increasing shearing in both …

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Sheared-Flow Induced Confinement Transition In A Linear Magnetized Plasma, S. Zhou, W. W. Heidbrink, H. Boehmer, R. Mcwilliams, T. A. Carter, S. Vincena, B. Friedman, David A. Schaffner Jan 2012

Sheared-Flow Induced Confinement Transition In A Linear Magnetized Plasma, S. Zhou, W. W. Heidbrink, H. Boehmer, R. Mcwilliams, T. A. Carter, S. Vincena, B. Friedman, David A. Schaffner

Physics Faculty Research and Scholarship

A magnetized plasma cylinder (12 cm in diameter) is induced by an annular shape obstacle at the Large Plasma Device [W. Gekelman, H. Pfister, Z. Lucky, J. Bamber, D. Leneman, and J. Maggs, Rev. Sci. Instrum. 62, 2875 (1991)]. Sheared azimuthal flow is driven at the edge of the plasma cylinder through edge biasing. Strong fluctuations of density and potential (δn/n~eδφ/kTe~0.5) are observed at the plasma edge, accompanied by a large density gradient (Ln=∣∣∇lnn∣∣−1~2cm) and shearing rate (γ~300kHz). Edge turbulence and cross-field transport are modified by changing the bias voltage (Vbias) on the obstacle and the axial magnetic field …

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Energy Dynamics In A Simulation Of Lapd Turbulence, B. Friedman, T. A. Carter, M. V. Umansky, David A. Schaffner, B. Dudson Jan 2012

Energy Dynamics In A Simulation Of Lapd Turbulence, B. Friedman, T. A. Carter, M. V. Umansky, David A. Schaffner, B. Dudson

Physics Faculty Research and Scholarship

Energy dynamics calculations in a 3D fluid simulation of drift wave turbulence in the linear Large Plasma Device [W. Gekelman et al., Rev. Sci. Instrum. 62, 2875 (1991)] illuminate processes that drive and dissipate the turbulence. These calculations reveal that a nonlinear instability dominates the injection of energy into the turbulence by overtaking the linear drift wave instability that dominates when fluctuations about the equilibrium are small. The nonlinear instability drives flute- like (kk 1⁄4 0) density fluctuations using free energy from the background density gradient. Through nonlinear axial wavenumber transfer to kk 61⁄4 0 fluctuations, the nonlinear instability accesses …

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Single-Crystal X-Ray Diffraction, Isolated-Molecule And Cluster Electronic Structure Calculations, And Scanning Electron Microscopy In An Organic Solid: Models For Intramolecular Motion In 4,4'-Dimethoxybiphenyl., Xianlong Wang, Loolita Rotkina, Hong Su, Peter A. Beckmann Jan 2012

Single-Crystal X-Ray Diffraction, Isolated-Molecule And Cluster Electronic Structure Calculations, And Scanning Electron Microscopy In An Organic Solid: Models For Intramolecular Motion In 4,4'-Dimethoxybiphenyl., Xianlong Wang, Loolita Rotkina, Hong Su, Peter A. Beckmann

Physics Faculty Research and Scholarship

This paper brings together field emission scanning electron microscopy, single-crystal X-ray diffraction, and density functional electronic structure calculations in both an isolated molecule and a cluster of seven whole and fourteen half molecules of 4,4′-dimethoxybiphenyl to investigate coupled methyl-group rotation (over a barrier) and methoxy-group libration (meaning a rotation from the ground state not all the way to the transition state and back again). The structure of the isolated molecule, determined by the electronic structure calculations, is compared with the structure of the molecule found in the crystal. As the methyl group rotates from its ground state to its transition …

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Nonexponential Solid State 1h And 19f Spin–Lattice Relaxation, Single-Crystal X-Ray Diffraction, And Isolated-Molecule And Cluster Electronic Structure Calculations In An Organic Solid: Coupled Methyl Group Rotation And Methoxy Group Libration In 4,4′-Dimethoxyoctafluorobiphenyl, Donald P. Fahey, William G. Dougherty Jr, W. Scott Kassel, Xianlong Wang, Peter A. Beckmann Jan 2012

Nonexponential Solid State 1h And 19f Spin–Lattice Relaxation, Single-Crystal X-Ray Diffraction, And Isolated-Molecule And Cluster Electronic Structure Calculations In An Organic Solid: Coupled Methyl Group Rotation And Methoxy Group Libration In 4,4′-Dimethoxyoctafluorobiphenyl, Donald P. Fahey, William G. Dougherty Jr, W. Scott Kassel, Xianlong Wang, Peter A. Beckmann

Physics Faculty Research and Scholarship

We investigate the relationship between intramolecular rotational dynamics and molecular and crystal structure in 4,4′-dimethoxyoctafluorobiphenyl. The techniques are electronic structure calculations, X-ray diffractometry, and 1H and 19F solid state nuclear magnetic resonance relaxation. We compute and measure barriers for coupled methyl group rotation and methoxy group libration. We compare the structure and the structure-motion relationship in 4,4′-dimethoxyoctafluorobiphenyl with the structure and the structure-motion relationship in related compounds in order to observe trends concerning the competition between intramolecular and intermolecular interactions. The 1H spin–lattice relaxation is nonexponential in both the high-temperature short-correlation time limit and in the low-temperature long-correlation time limit, …

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So Why Would A Pigeon Stand On One Leg (Or Limp Without Hurting)?, Zdeslav Hrepic Jan 2012

So Why Would A Pigeon Stand On One Leg (Or Limp Without Hurting)?, Zdeslav Hrepic

Faculty Bibliography

No abstract provided.

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Chromoelectric Oscillations In A Dynamically Evolving Anisotropic Background, Wojciech Florkowski, Radoslaw Ryblewski, Michael T. Strickland Jan 2012

Chromoelectric Oscillations In A Dynamically Evolving Anisotropic Background, Wojciech Florkowski, Radoslaw Ryblewski, Michael T. Strickland

Physics and Astronomy Faculty Publications

Strickland and collaborators derive and solve the equations necessary to describe oscillators of a chromoelectric field in an expanding quark gluon plasma.

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Multimessenger Astronomy: Modeling Gravitational And Electromagnetic Radiations From A Stellar Binary System, Kevin Kern Jan 2012

Multimessenger Astronomy: Modeling Gravitational And Electromagnetic Radiations From A Stellar Binary System, Kevin Kern

Bridges: A Journal of Student Research

Our Sun is one of roughly 100 billion other stars that make up the Milky Way Galaxy. Two-thirds of all stars are paired off, with a gravitational bond between the two stars. Such systems are known as stellar binaries. Although these binaries are very common in the galaxy, there is much yet to be learned about their formation, evolution, and interactions. The approach taken in this thesis is to produce simulated data representing the expected measurements that an observational astronomer would collect. We attempt to simulate three different stellar binary star systems: an eclipsing binary, a spectroscopic binary, and a …

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Analysis Of Entanglement And Logic Gate Implementation In Generic Two-Level Systems, Jonathan Jones Jan 2012

Analysis Of Entanglement And Logic Gate Implementation In Generic Two-Level Systems, Jonathan Jones

Undergraduate Honors Theses

An N-atom quantum system interacting with a single cavity field mode serves as an intuitive and useful model for many areas of quantum information science. We extend this model to describe artificial systems composed of quantum dots and Josephson junction devices as well. In addition, we include the dipole interactions characteristic of such systems. We use Bell-type inequalities and concurrence to examine the development of entanglement in the specific cases of two- and three-atom systems, and find that the effect of dipole interactions on entanglement generation depends heavily on the initial state of the system. Finally, we propose a …

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Measurement Of The Inclusive Jet Cross Section In Pp̅ Collisions At √S= 1.96 Tev, V. M. Abazov, Kenneth A. Bloom, Daniel R. Claes, Kayle Devaughan, Aaron Dominguez, Michael Eads, Ioannis Katsanos, Sudhir Malik, Gregory Snow, P. Svoisky, M. Takahashi, M. Voutilainen Jan 2012

Measurement Of The Inclusive Jet Cross Section In Pp̅ Collisions At √S= 1.96 Tev, V. M. Abazov, Kenneth A. Bloom, Daniel R. Claes, Kayle Devaughan, Aaron Dominguez, Michael Eads, Ioannis Katsanos, Sudhir Malik, Gregory Snow, P. Svoisky, M. Takahashi, M. Voutilainen

Kenneth Bloom Publications

We present a measurement of the inclusive jet cross section using the Run II cone algorithm and data collected by the D0 experiment in pp̅ collisions at a center-of-mass energy √s= 1.96 TeV, corresponding to an integrated luminosity of 0.70 fb-1. The jet energy calibration and the method used to extract the inclusive jet cross section are described.We discuss the main uncertainties, which are dominated by the jet energy scale uncertainty. The results cover jet transverse momenta from 50 GeV to 600 GeV with jet rapidities in the range -2.4 to 2.4 and are compared to predictions …

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Search For Doubly Charged Higgs Boson Pair Production In Pp̅ Collisions At √S = 1.96 Tev, V. M. Abazov, Kenneth A. Bloom, Daniel R. Claes, Kayle Devaughan, Aaron Dominguez, Michael Eads, D. Johnston, Ioannis Katsanos, Sudhir Malik, Gregory Snow Jan 2012

Search For Doubly Charged Higgs Boson Pair Production In Pp̅ Collisions At √S = 1.96 Tev, V. M. Abazov, Kenneth A. Bloom, Daniel R. Claes, Kayle Devaughan, Aaron Dominguez, Michael Eads, D. Johnston, Ioannis Katsanos, Sudhir Malik, Gregory Snow

Kenneth Bloom Publications

We present a search for pair production of doubly charged Higgs bosons in the processes qq̅→H++H-- decaying through H±±→τ±τ±, µ±τ±,µ±µ±. The search is performed in pp̅ collisions at a center-of-mass energy of √s = 1.96 TeV using an integrated luminosity of up to 7.0 fb-1 collected by the D0 experiment at the Fermilab Tevatron Collider. The results are used to set 95% C.L. limits on the pair production cross section of doubly charged Higgs bosons and on their mass for different H …

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Measurement Of The Λb Cross Section And The Λb To Λb Ratio With J/Ψλ Decays In Pp Collisions At √S = 7 Tev, Cms Collaboration, Ekaterina Avdeeva, Kenneth A. Bloom, S. Bose, Jamila Butt, Daniel R. Claes, Aaron Dominguez, Michael Eads, P. Jindal, J. Keller, Ilya Kravchenko, J. Lazo-Flores, Helena Malbouisson, Sudhir Malik, Gregory Snow Jan 2012

Measurement Of The Λb Cross Section And The Λb To Λb Ratio With J/Ψλ Decays In Pp Collisions At √S = 7 Tev, Cms Collaboration, Ekaterina Avdeeva, Kenneth A. Bloom, S. Bose, Jamila Butt, Daniel R. Claes, Aaron Dominguez, Michael Eads, P. Jindal, J. Keller, Ilya Kravchenko, J. Lazo-Flores, Helena Malbouisson, Sudhir Malik, Gregory Snow

Kenneth Bloom Publications

The Λb differential production cross section and the cross section ratio σ(Λ̅b )/σ(Λb) are measured as functions of transverse momentum pΛbT and rapidity |yΛb | in pp collisions at √ s = 7 TeV using data collected by the CMS experiment at the LHC. The measurements are based on Λb decays reconstructed in the exclusive final state J/ψΛ, with the subsequent decays J/ψ →μ+μ− and Λ→pπ, using a data sample corresponding to an integrated luminosity of 1.9 fb−1. The product …

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Search For Heavy Long-Lived Charged Particles In Pp Collisions At √S = 7 Tev, Cms Collaboration, Ekaterina Avdeeva, Kenneth A. Bloom, S. Bose, J. Butt, Daniel R. Claes, Aaron Dominguez, Michael Eads, P. Jindal, J. Keller, Ilya Kravchenko, J. Lazo-Flores, H. Malbouisson, Sudhir Malik, Gregory Snow Jan 2012

Search For Heavy Long-Lived Charged Particles In Pp Collisions At √S = 7 Tev, Cms Collaboration, Ekaterina Avdeeva, Kenneth A. Bloom, S. Bose, J. Butt, Daniel R. Claes, Aaron Dominguez, Michael Eads, P. Jindal, J. Keller, Ilya Kravchenko, J. Lazo-Flores, H. Malbouisson, Sudhir Malik, Gregory Snow

Kenneth Bloom Publications

The result of a search for heavy long-lived charged particles produced in pp collisions at √s = 7 TeV at the LHC is described. The data sample has been collected using the CMS detector and corresponds to an integrated luminosity of 5.0 fb−1. The inner tracking detectors are used to define a sample of events containing tracks with high momentum and high ionization energy loss. A second sample of events, which have high-momentum tracks satisfying muon identification requirements in addition to meeting high-ionization and long time-of-flight requirements, is analyzed independently. In both cases, the results are consistent …

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Diffuse Optical Imaging Using Decomposition Methods, Binlin Wu, M. Alrubaiee, W. Cai, M. Xu, S. K. Gayen Jan 2012

Diffuse Optical Imaging Using Decomposition Methods, Binlin Wu, M. Alrubaiee, W. Cai, M. Xu, S. K. Gayen

Publications and Research

Diffuse optical imaging (DOI) for detecting and locating targets in a highly scattering turbid medium is treated as a blind source separation (BSS) problem. Three matrix decomposition methods, independent component analysis (ICA), principal component analysis (PCA), and nonnegative matrix factorization (NMF) were used to study the DOI problem. The efficacy of resulting approaches was evaluated and compared using simulated and experimental data. Samples used in the experiments included Intralipid-10% or Intralipid-20% suspension in water as the medium with absorptive or scattering targets embedded.

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Fluids, Anomalies And The Chiral Magnetic Effect: A Group-Theoretic Formulation, V. Parameswaran Nair, Rashmi Ray, Shubho Roy Jan 2012

Fluids, Anomalies And The Chiral Magnetic Effect: A Group-Theoretic Formulation, V. Parameswaran Nair, Rashmi Ray, Shubho Roy

Publications and Research

It is possible to formulate fluid dynamics in terms of group-valued variables. This is particularly suited to the cases where the fluid has nonabelian charges and is coupled to nonabelian gauge fields. We explore this formulation further in this paper. An action for a fluid of relativistic particles (with and without spin) is given in terms of the Lorentz and Poincare (or de Sitter) groups. Considering the case of particles with flavor symmetries, a general fluid action which also incorporates all flavor anomalies is given. The chiral magnetic and chiral vorticity effects as well as the consequences of the mixed …

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Yousef Studies The Physics Of Life And Health, Aldemaro Romero Jr. Jan 2012

Yousef Studies The Physics Of Life And Health, Aldemaro Romero Jr.

Publications and Research

No abstract provided.

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Hamad Studies, Teaches Properties Of Light, Aldemaro Romero Jr. Jan 2012

Hamad Studies, Teaches Properties Of Light, Aldemaro Romero Jr.

Publications and Research

No abstract provided.

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A Systematic Study Of Transport, Magnetic And Thermal Properties Of Layered Iridates, Oleksandr B. Korneta Jan 2012

A Systematic Study Of Transport, Magnetic And Thermal Properties Of Layered Iridates, Oleksandr B. Korneta

Theses and Dissertations--Physics and Astronomy

A unique feature of the 5d-iridates is that the spin-orbit interaction (SOI) and Coulomb interactions U are of comparable strength and therefore compete vigorously. The relative strength of these interactions stabilizes new exotic ground states that provide a fertile ground for studying new physics. SOI is proportional to Z^4 (Z is the atomic number), and it is now recognized that strong SOI can drive novel narrow-gap insulating states in heavy transition metal oxides such as iridates. Indeed, strong SOI necessarily introduces strong lattice degrees of freedom that become critical to new physics in the iridates. This dissertation thoroughly examines a …

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Stability And Clustering Of Self-Similar Solutions Of Aggregation Equations, Hui Sun, David Uminsky, Andrea L. Bertozzi Jan 2012

Stability And Clustering Of Self-Similar Solutions Of Aggregation Equations, Hui Sun, David Uminsky, Andrea L. Bertozzi

Mathematics

In this paper we consider the linear stability of a family of exact collapsing similarity solutions to the aggregation equation ρ t = ∇ · (ρ∇K * ρ) in Rd , d ⩾ 2, where K(r) = r γ/γ with γ > 2. It was previously observed [Y. Huang and A. L. Bertozzi, “Self-similar blowup solutions to an aggregation equation in Rn,” J. SIAM Appl. Math.70, 2582–2603 (Year: 2010)]10.1137/090774495 that radially symmetric solutions are attracted to a self-similar collapsing shell profile in infinite time for γ > 2. In this paper we compute the stability of the …

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Investigating Mountain Waves In Mtm Image Data At Cerro Pachon, Chile, Neal R. Criddle, M. J. Taylor, P.-D. Pautet, Y. Zhao, G. Swenson, A. Liu Jan 2012

Investigating Mountain Waves In Mtm Image Data At Cerro Pachon, Chile, Neal R. Criddle, M. J. Taylor, P.-D. Pautet, Y. Zhao, G. Swenson, A. Liu

Neal R Criddle

Gravity waves are important drivers of chemical species mixing, energy and momentum transfer into the MLT (~80 - 100 km) region. As part of a collaborative program involving instruments from several institutions Utah State University has operated a Mesospheric Temperature Mapper (MTM) at the new Andes Lidar Observatory (ALO) on Cerro Pachon (30.2°S, 70.7°W) Since August 2009. A primary goal of this program is to quantify the impact of mountain waves on the MLT region. The Andes region is an excellent natural laboratory for investigating gravity wave influences on the MLT region, especially the study of mountain waves, created by …

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Measurement Of Semiconductor Surface Potential Using The Scanning Electron Microscope, Jennifer T. Heath, Chun-Sheng Jiang, Mowafak M. Al-Jassim Jan 2012

Measurement Of Semiconductor Surface Potential Using The Scanning Electron Microscope, Jennifer T. Heath, Chun-Sheng Jiang, Mowafak M. Al-Jassim

Faculty Publications

We calibrate the secondary electron signal from a standard scanning electron microscope to voltage, yielding an image of the surface or near-surface potential. Data on both atomically abrupt heterojunction GaInP/GaAs and diffused homojunction Si solar cell devices clearly show the expected variation in potential with position and applied bias, giving depletion widths and locating metallurgical junctions to an accuracy better than 10 nm. In some images, distortion near the p-n junction is observed, seemingly consistent with the effects of lateral electric fields (patch fields). Reducing the tube bias removes this distortion. This approach results in rapid and straightforward collection of …

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