# Elementary Particles and Fields and String Theory Commons™

## All Articles in Elementary Particles and Fields and String Theory

900 full-text articles. Page 1 of 32.

Precision Measurement Of The Beam-Normal Single-Spin Asymmetry In Forward-Angle Elastic Electron-Proton Scattering, 2020 William & Mary

#### Precision Measurement Of The Beam-Normal Single-Spin Asymmetry In Forward-Angle Elastic Electron-Proton Scattering, Qweak Collaboration, David Armstrong, Wouter Deconinck, K. Bartlett, J. C. Cornejo, R. D. Carlini, James F. Dowd, J. M. Finn, Valerie M. Gray, K. Grimm, J. R. Hoskins, J. P. Leckey, Jeong Han Lee, Joshua A. Magee, Victoria F. Owen

##### Arts & Sciences Articles

A beam-normal single-spin asymmetry generated in the scattering of transversely polarized electrons from unpolarized nucleons is an observable related to the imaginary part of the two-photon exchange process. We report a 2% precision measurement of the beam-normal single-spin asymmetry in elastic electron-proton scattering with a mean scattering angle of theta_lab = 7.9 degrees and a mean energy of 1.149 GeV. The asymmetry result is B_n = -5.194 +- 0.067 (stat) +- 0.082 (syst) ppm. This is the most precise measurement of this quantity available to date and therefore provides a stringent test of two-photon exchange models at far-forward scattering ...

2020 The Graduate Center, City University of New York

#### Particle Dynamics In Anti-De Sitter Space By Eih Method, Jiusi Lei

##### Dissertations, Theses, and Capstone Projects

Following the work of Einstein, Infeld and Hoffmann, we show that particle dynamics in Anti-de Sitter spacetime can be built up by regarding singularities in spacetime manifold as the source of particles.

Since gauge fields play a foundational role in the action, the singularities are chosen to be point-like instantons. Their winding number, defined by an integration on the spheres surrounding those singularities, will turn out to be related to their masses. And their action, derived from the Chern-Simons forms, will be a co-adjoint orbit action, with group element g ∈ SO(4, 2) describing the collective coordinates of the particle ...

2020 Old Dominion University

#### Simulation And Development Of The Radial Time Projection Chamber For The Bonus12 Experiment In Clas12, Nathan M. Dzbenski

##### Physics Theses & Dissertations

Knowledge of the structure of nucleons (i:e: protons and neutrons) is a central topic of interest to nuclear/particle physicists. Much more is known about the structure of the proton than the neutron due to the lack of high-density free neutron targets. The Barely Off-shell Nucleon Structure experiment (BONuS12) at Jefferson Lab (JLab) is a second generation experiment upgraded/optimized to advance our knowledge of the neutron's structure using the deep-inelastic scattering of electrons off deuterium. Typically, since deuterium is a nuclear target, corrections for off-shell and nuclear binding effects must be taken into account in order to ...

2020 The Graduate Center, City University of New York

#### Generalized Four-Dimensional Effective Hadronic Supersymmetry Based On Quantum Chromodynamics (Qcd), Enxi Yu

##### Dissertations, Theses, and Capstone Projects

New discovery in multiple laboratories around the globe has shown a supersymmetry between hadrons—baryons and mesons. In order to generalize the phenomenological hadronic supersymmetry, the spin-flavor SU(6) symmetry need an extension. This thesis present how we can extend SU(6) symmetry so that hadronic supersymmetry can be included. In the future, this extension can be also applied to pentaquark and tetraquark bags, for which there is an ongoing research in laboratories.

Small-X Qcd Calculations With A Biased Ensemble, 2020 The Graduate Center, City University of New York

#### Small-X Qcd Calculations With A Biased Ensemble, Gary Kapilevich

##### Dissertations, Theses, and Capstone Projects

In this dissertation, I will argue that we can study functional fluctuations in unintegrated gluon distributions, in the MV model as well as JIMWLK, using reweighting techniques, which will allow me to calculate QCD observables with "biased ensembles". This technique will enable me to study rare functional configurations of the gluon distributions, that might have been selected for in, for example, the centrality criteria used by the ATLAS and ALICE collaborations. After a review of these techniques, as well as a review of QCD physics at high energy in general, I will use biased ensembles to compute observables in two ...

2020 Macalester College

#### Searching For Doublet Vectorlike Leptons Using The Atlas Particle Detector, Brynn Keller

##### Macalester Journal of Physics and Astronomy

Vectorlike leptons are a simple extension of the standard model, akin to a fourth family of leptons. This paper describes aspects of the preparation for a search for VLLs at an ATLAS particle collider. During this research, signal and control regions were determined with use of a Monte Carlo simulation in order to best estimate where to measure different kinds of background and where to search for a potential signal. These signal and control regions were optimized with respect to MET, LT, and number of light and heavy leptons with a goal of a 95\% confidence limit.

Coherent Captain Mills: The Search For Sterile Neutrinos, 2020 Embry-Riddle Aeronautical University

#### Coherent Captain Mills: The Search For Sterile Neutrinos, Ashley Elliott, Jeramy Gordon, Jonah Greenwood, Rachel Lake, Ryder Moreno, Emily Strawn, Kate Walker

##### Discovery Day - Prescott

The observation of neutrino oscillations confirms that the active neutrinos (νe, νμ, ντ) are comprised of three mass eigenstates with Δm2 values between 10-3 to 10-5 eV2 . However, a persistent phenomenon has been observed at LSND, MiniBooNE and other shortbaseline experiments (SBE) where Δm2 ~ 1eV2 and is not compatible with the current mixing between mass eigenstates. However, a 4th neutrino, a sterile neutrino (νs) that doesn’t participate in weak interactions could explain the phenomena observed as SBE’s. An experiment has been constructed at TA-53 at Los Alamos National Laboratory to investigate this large Δm2 ~ 1eV2 and determine conclusively ...

Physics 516: Electromagnetic Phenomena (Spring 2020), 2020 University of Pennsylvania

#### Physics 516: Electromagnetic Phenomena (Spring 2020), Philip C. Nelson

##### Department of Physics Papers

These course notes are made publicly available in the hope that they will be useful. All reports of errata will be gratefully received. I will also be glad to hear from anyone who reads them, whether or not you find errors: pcn@upenn.edu.

2020 William & Mary

#### Studying And Correcting For Helicity-Correlated False Asymmetries In The Prex Ii And Crex Experiments, Carrington Metts

The goal of the PREx II and CREx experiments are to determine the size of the neutron distribution in 208Pb and 48Ca, respectively. Because these isotopes have a large discrepancy in between the number of neutrons and protons, theoretical models predict that some of the neutrons will arrange themselves in a “skin” on the nucleus’s surface. Prior results from the PREx I experiment confirmed the existence of the neutron skin in 208Pb. All of the mentioned experiments employ the technique of parity-violating electron scattering. Electron-nucleus weak interactions are dominated by electron-neutron scattering, which is an order ...

Consistency Checks For Two-Body Finite-Volume Matrix Elements. Ii. Perturbative Systems, 2020 Old Dominion University

#### Consistency Checks For Two-Body Finite-Volume Matrix Elements. Ii. Perturbative Systems, Raúl A. Briceño, Maxwell T. Hansen, Andrew W. Jackura

##### Physics Faculty Publications

Using the general formalism presented in [Phys. Rev. D 94, 013008 (2016); Phys. Rev. D 100, 034511 (2019)], we study the finite-volume effects for the 2 þ J → 2 matrix element of an external current coupled to a two-particle state of identical scalars with perturbative interactions. Working in a finite cubic volume with periodicity L, we derive a 1=L expansion of the matrix element through O(1=L5) and find that it is governed by two universal current-dependent parameters, the scalar charge and the threshold two particle form factor. We confirm the result through a numerical study of ...

293— Moly - Monitoring Oxygen Levels In Ntof Scintillators Using Cosmic Ray Muons, 2020 SUNY Geneseo

#### 293— Moly - Monitoring Oxygen Levels In Ntof Scintillators Using Cosmic Ray Muons, Sean King, Matthew Signor

##### GREAT Day

High Energy Density Physics and Inertial Confinement Fusion facilities employ nTOF methods to measure neutron energies. Laser induced fusion facilities use the beam pulse as a start signal and Xylene scintillators as the stop signal to obtain the time of flight. To improve timing performance, the scintillator liquid is quenched with oxygen reducing the light production. However, oxygen reacts with the scintillator liquid causing the detector photo flash decay time to increase that reduces the energy resolution of the detector. An in-situ monitoring system which uses cosmic ray muons to determine the oxygen concentration, is being developed at SUNY Geneseo ...

Charged Particle Identification Using Calorimetry And Tracking At The Belle Ii Experiment, 2020 University of Louisville

#### Charged Particle Identification Using Calorimetry And Tracking At The Belle Ii Experiment, Joseph T. Nunziata, Atanu Pathak, Swagato Banerjee

##### Undergraduate Arts and Research Showcase

Particle identification (PID) is a critical procedure carried out in high energy physics experiments in search of new physics. When particles of matter (i.e., an electron) and antimatter (i.e., a positron) collide, new types of particles may form given certain conditions. Such particles may be classified as hadrons--which feel the strong nuclear force--and leptons--which do not. Identifying particles at the Belle II experiment is done by combining the measurement of energy deposited in the calorimeter with the measurement of track momentum in the tracker. In a tau lepton ($\tau$) decay sample, particles such as electrons, muons, and pions ...

Magnetic Forces In The Absence Of A Classical Magnetic Field, 2020 Chapman University

#### Magnetic Forces In The Absence Of A Classical Magnetic Field, Ismael L. Paiva, Yakir Aharonov, Jeff Tollaksen, Mordecai Waegell

##### Mathematics, Physics, and Computer Science Faculty Articles and Research

It is shown that, in some cases, the effect of discrete distributions of flux lines in quantum mechanics can be associated with the effect of continuous distributions of magnetic fields with special symmetries. In particular, flux lines with an arbitrary value of magnetic flux can be used to create energetic barriers, which can be used to confine quantum systems in specially designed configurations. This generalizes a previous work where such energy barriers arose from flux lines with half-integer fluxons. Furthermore, it is shown how the Landau levels can be obtained from a two-dimensional grid of flux lines. These results suggest ...

Measurement Of The Photon Beam Asymmetry In Γp → K+Σ0 At EΓ = 8.5 Gev With Gluex, 2020 Old Dominion University

#### Measurement Of The Photon Beam Asymmetry In Γp → K+Σ0 At EΓ = 8.5 Gev With Gluex, Nilanga Indrajie Wickramaarachchi

##### Physics Theses & Dissertations

In this work the photon beam asymmetry Σ for the reaction γp K+ Σ0(1193) is measured using the GlueX experiment in Hall D at Jefferson Lab. The analysis used data that were collected using a linearly polarized photon beam in the energy range (8.2 - 8.8) GeV incident on a liquid hydrogen target. The beam asymmetries are measured as a function of the Mandelstam variable t and as a single value for the low u region. These are the first exclusive measurements of the photon beam asymmetry Σ in this reaction at energies above the baryon resonance ...

The Clas12 Software Framework And Event Reconstruction, 2020 Old Dominion University

#### The Clas12 Software Framework And Event Reconstruction, V. Ziegler, N. A. Baltzell, F. Bossù, D. S. Carman, P. Chatanon, M. Contalbrigo, J. Newton, M. Ungaro

##### Physics Faculty Publications

We describe offline event reconstruction for the CEBAF Large Acceptance Spectrometer at 12 GeV (CLAS12), including an overview of the offline reconstruction framework and software tools, a description of the algorithms developed for the individual detector subsystems, and the overall approach for charged and neutral particle identification. We also present the scheme for data processing and the code management procedures.

2020 Old Dominion University

#### Heavy Quark Expansion For Heavy-Light Light-Cone Operators, Shuai Zhao

##### Physics Faculty Publications

We generalize the celebrated heavy quark expansion to nonlocal QCD operators. By taking nonlocal heavy-light current on the light-cone as an example, we confirm that the collinear singularities are common between QCD operator and the corresponding operator in heavy quark effective theory (HQET), at the leading power of 1/M expansion. Based on a perturbative calculation in operator form at one-loop level, a factorization formula linking QCD and HQET operators is investigated and the matching coefficient is determined. The matching between QCD and HQET light-cone distribution amplitudes (LCDAs) as well as other momentum distributions of hadron can be derived as ...

2020 University of Massachusetts Amherst

#### Search For Displaced Hadronic Vertices In The Atlas Inner Detector And Muon Spectrometer In P-P Collisions At √S = 13 Tev At The Lhc, Margaret S. Lutz

##### Doctoral Dissertations

A search is performed for long-lived neutral particles using 33 fb−1 of 13 TeV proton-proton collision data produced by the LHC and collected by the ATLAS detector during 2016. This search focuses on the topology in which pairs of displaced hadronic jets are produced, with one in the inner detector and the other in the muon spectrometer. Special techniques are used to reconstruct the displaced decays. One event is found passing the full signal selection, which is consistent with the back- ground estimation. Limits are set at a 95% upper confidence level on the BR × σ for a SM ...

Truncations Of W (Infinity) Algebras, 2020 Stony Brook University

#### Truncations Of W (Infinity) Algebras, Mohammed Akram Fellah

##### Department of Physics Faculty Publications

We introduce a new class of Vertex Operator Algebras Y+ and their duals, which generalize the standard W-algebras WN of type sl(N). These algebras can be defined in terms of junctions of boundary conditions and interfaces in the GL-twisted N = 4 Super Yang Mills gauge theory.

The aim of these technical calculations is to find the relation of these ortho-symplectic Y-algebras to truncations of even W\infinity.

Large N Fields And Holography, 2020 University of Kentucky

#### Large N Fields And Holography, Animik Ghosh

##### Theses and Dissertations--Physics and Astronomy

We study (nearly) AdS/CFT holography within the context of the Sachdev-Ye- Kitaev (SYK) model. We present a systematic procedure to extract the dynamics of the low energy Schwarzian mode in SYK type models with a single energy scale J and emergent reparametrization symmetry in the infrared within the framework of perturbation theory. We develop a systematic approach using Feynman diagrams in bilocal theory to obtain a formal expression for the enhanced and O(1) corrections to the bilocal propagator and apply this general technique to large q SYK. We show that the Schwarzian theory describes a sector of a ...

Validating The Belle2 Physicslist In Geant4 V10.1.2, 2020 University of Louisville

#### Validating The Belle2 Physicslist In Geant4 V10.1.2, Dustyn D Hofer, Swagato Banerjee Dr., David N. Brown Dr., Atanu Pathak

##### Undergraduate Arts and Research Showcase

Since the start of software development at the Belle II experiment operating at the KEK national laboratory in Tsukuba, Japan, the simulation tool kit Geant4 has undergone several updates. As a member in the ongoing collaboration, the University of Louisville’s High Energy Physics (HEP) group is striving to validate newer versions of Geant4 to maximize improvements of physics performance.We have simulated the performance of a new physics list sub-module, the "Belle2 PhysicsList", with improved modeling of hadronic shower shape and standard electromagnetic processes. Using a reconstruction-based selection procedure on tau-pair events decaying into a final state consisting ofe ...