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Cosmic Ray Muons In The Standard Model Of Fundamental Particles, Angel Gutarra-Leon, Jorge Del Carpio Arispe, Cioli Barazandeh, Walerian Majewski 2018 George Mason University

Cosmic Ray Muons In The Standard Model Of Fundamental Particles, Angel Gutarra-Leon, Jorge Del Carpio Arispe, Cioli Barazandeh, Walerian Majewski

Exigence

Muons are one of the twelve fundamental particle types of matter, having relatively long free-particle lifetime. A muon decays into three other light particles (leptons) through action of the “weak” force, transmitted by the so-called “heavy photons” - bosons W+/W-. Muons are present in the secondary cosmic ray showers in the atmosphere and reach the sea level. By detecting the delay time between arrival of the muon and an appearance of the decay electron in our single scintillation detector, we measured the muon’s average lifetime at rest in the material of our detector. This compares well with the established ...


Time-Resolved Electron (E,2E) Momentum Spectroscopy: Application To Laser-Driven Electron Population Transfer In Atoms, Hua-Chieh Shao, Anthony F. Starace 2018 University of Nebraska - Lincoln

Time-Resolved Electron (E,2E) Momentum Spectroscopy: Application To Laser-Driven Electron Population Transfer In Atoms, Hua-Chieh Shao, Anthony F. Starace

Anthony F. Starace Publications

Owing to its ability to provide unique information on electron dynamics, time-resolved electron momentum spectroscopy (EMS) is used to study theoretically a laser-driven electronic motion in atoms. Specifically, a chirped laser pulse is used to adiabatically transfer the populations of lithium atoms from the ground state to the first excited state. During this process, impact ionization near the Bethe ridge by time-delayed ultrashort, high-energy electron pulses is used to image the instantaneous momentum density of this electronic population transfer. Simulations with 100 fs and 1 fs pulse durations demonstrate the capability of EMS to image the time-varying momentum density, including ...


Light-Nuclei Spectra From Chiral Dynamics, M. Piarulli, A. Baroni, L. Girlanda, A. Kievsky, A. Lovato, Ewing Lusk, L. E. Marcucci, Steven C. Pieper, R. Schiavilla, M, Viviani, R. B. Wiringa 2018 Old Dominion University

Light-Nuclei Spectra From Chiral Dynamics, M. Piarulli, A. Baroni, L. Girlanda, A. Kievsky, A. Lovato, Ewing Lusk, L. E. Marcucci, Steven C. Pieper, R. Schiavilla, M, Viviani, R. B. Wiringa

Physics Faculty Publications

In recent years local chiral interactions have been derived and implemented in quantum Monte Carlo methods in order to test to what extent the chiral effective field theory framework impacts our knowledge of few- and many-body systems. In this Letter, we present Green's function Monte Carlo calculations of light nuclei based on the family of local two-body interactions presented by our group in a previous paper in conjunction with chiral three-body interactions fitted to bound- and scattering-state observables in the three-nucleon sector. These interactions include Δ intermediate states in their two-pion-exchange components. We obtain predictions for the energy levels ...


High Field Q Slope And The Effect Of Low-Temperature Baking At 3 Ghz, G. Ciovati, G. Eremeev, F. Hannon 2018 Old Dominion University

High Field Q Slope And The Effect Of Low-Temperature Baking At 3 Ghz, G. Ciovati, G. Eremeev, F. Hannon

Physics Faculty Publications

A strong degradation of the unloaded quality factor with field, called high field Q slope, is commonly observed above Bp ≅ 100 mT in elliptical superconducting niobium cavities at 1.3 and 1.5 GHz. In the present experiments several 3 GHz niobium cavities were measured up to and above Bp ≅ 100 mT. The measurements show that a high field Q slope phenomenon limits the field reach at this frequency, that the high field Q slope onset field depends weakly on the frequency, and that the high field Q slope can be removed by the typical empirical solution of ...


Muon-Neutrino Electron Elastic Scattering And A Search For The Muon-Neutrino Magnetic Moment In The Nova Near Detector, Biao Wang 2017 Southern Methodist University

Muon-Neutrino Electron Elastic Scattering And A Search For The Muon-Neutrino Magnetic Moment In The Nova Near Detector, Biao Wang

Physics Theses and Dissertations

We use the NOvA near detector and the NuMI beam at Fermilab to study the neutrino-electron elastic scattering and the muon neutrino magnetic process beyond the Standard Model physics. The particle identifications of neutrino on electron elastic scattering are trained by using the multi-layer neural networks. This thesis provides a general discussion of this technique and shows a good agreement between data and MC for the neutrino-electron elastic weak scattering. By using 3.62e20 POT dataset in the NOvA near detector, we find 1.58e-9 Bohr magneton as the 90% C.L. upper limit. We also find a sensitivity of ...


Introduction To The Usu Library Of Solutions To The Einstein Field Equations, Ian M. Anderson, Charles G. Torre 2017 ian.anderson@usu.edu

Introduction To The Usu Library Of Solutions To The Einstein Field Equations, Ian M. Anderson, Charles G. Torre

Tutorials on... in 1 hour or less

This is a Maple worksheet providing an introduction to the USU Library of Solutions to the Einstein Field Equations. The library is part of the DifferentialGeometry software project and is a collection of symbolic data and metadata describing solutions to the Einstein equations.


A Measurement Of The Wγ Cross Section At √S = 8 Tev In Pp Collisions With The Cms Detector, Ekaterina Avdeeva 2017 University of Nebraska-Lincoln

A Measurement Of The Wγ Cross Section At √S = 8 Tev In Pp Collisions With The Cms Detector, Ekaterina Avdeeva

Theses, Dissertations, and Student Research: Department of Physics and Astronomy

A measurement of cross section of the Wγ → lνγ production in proton-proton collisions using 19.6 fb − 1 of LHC data collected by CMS detector at the center- √ of-mass collision energy of s = 8 TeV is reported. The W bosons are identified in their electron and muon decay modes. The process of Wγ production in the Standard Model (SM) involves a pure gauge boson coupling, a WWγ vertex, which allows one to test the electroweak sector of the SM in a unique way not achievable by studies of other processes. In addition to the total cross section, we measure the ...


Mode-Sum Prescription For Vacuum Polarization In Black Hole Spacetimes In Even Dimensions, Peter Taylor, Cormac Breen 2017 Dublin City University

Mode-Sum Prescription For Vacuum Polarization In Black Hole Spacetimes In Even Dimensions, Peter Taylor, Cormac Breen

Articles

We present a mode-sum regularization prescription for computing the vacuum polarization of a scalar field in static spherically symmetric black hole spacetimes in even dimensions. This is the first general and systematic approach to regularized vacuum polarization in higher even dimensions, building upon a previous scheme we developed for odd dimensions. Things are more complicated here since the even-dimensional propagator possesses logarithmic singularities which must be regularized. However, in spite of this complication, the regularization parameters can be computed in closed form in arbitrary even dimensions and for arbitrary metric function f(r). As an explicit example of our method ...


A Glimpse Of Gluons Through Deeply Virtual Compton Scattering On The Proton, M. Defurne, A. Marti Jimenez-Arguello, Z. Ahmed, H. Albataineh, K. Allada, K. A. Aniol, V. Bellini, M. Benali, W. Boeglin, P. Bertin, M. Canan, C. E. Hyde, M. N. H. Rashad 2017 Old Dominion University

A Glimpse Of Gluons Through Deeply Virtual Compton Scattering On The Proton, M. Defurne, A. Marti Jimenez-Arguello, Z. Ahmed, H. Albataineh, K. Allada, K. A. Aniol, V. Bellini, M. Benali, W. Boeglin, P. Bertin, M. Canan, C. E. Hyde, M. N. H. Rashad

Physics Faculty Publications

The internal structure of nucleons (protons and neutrons) remains one of the greatest outstanding problems in modern nuclear physics. By scattering high-energy electrons off a proton we are able to resolve its fundamental constituents and probe their momenta and positions. Here we investigate the dynamics of quarks and gluons inside nucleons using deeply virtual Compton scattering (DVCS)-a highly virtual photon scatters off the proton, which subsequently radiates a photon. DVCS interferes with the Bethe-Heitler (BH) process, where the photon is emitted by the electron rather than the proton. We report herein the full determination of the BH-DVCS interference by ...


Lattice Qcd Exploration Of Parton Pseudo-Distribution Functions, Kostas Orginos, Anatoly Radyushkin, Joseph Karpie, Savvas Zafeiropoulos 2017 Old Dominion University

Lattice Qcd Exploration Of Parton Pseudo-Distribution Functions, Kostas Orginos, Anatoly Radyushkin, Joseph Karpie, Savvas Zafeiropoulos

Physics Faculty Publications

We demonstrate a new method of extracting parton distributions from lattice calculations. The starting idea is to treat the generic equal-time matrix element M(Pz(3), z(3)(2)) as a function of the Ioffe time nu = Pz(3) and the distance z(3). The next step is to divide M(Pz(3), z(3)(2)) by the rest-frame density M(0, z(3)(2)). Our lattice calculation shows a linear exponential z(3)-dependence in the rest-frame function, expected from the Z(z(3)(2)) factor generated by the gauge link. Still, we observe that the ratio M (Pz ...


Doubly-Excited State Effects On Two-Photon Double Ionization Of Helium By Time-Delayed, Oppositely Circularly-Polarized Attosecond Pulses, Jean Marcel Ngoko Djiokap, Anthony F. Starace 2017 University of Nebraska-Lincoln

Doubly-Excited State Effects On Two-Photon Double Ionization Of Helium By Time-Delayed, Oppositely Circularly-Polarized Attosecond Pulses, Jean Marcel Ngoko Djiokap, Anthony F. Starace

Anthony F. Starace Publications

We study two-photon double ionization (TPDI) of helium by a pair of time-delayed (non-overlapping), oppositely circularly-polarized attosecond pulses whose carrier frequencies are resonant with 1Po doubly-excited states. All of our TPDI results are obtained by numerical solution of the two-electron time-dependent Schrödinger equation for the six-dimensional case of circularly-polarized attosecond pulses, and they are analyzed using perturbation theory (PT). As compared with the corresponding nonresonant TPDI process, we find that the doubly-excited states change the character of vortex patterns in the two-electron momentum distributions for the case of back-to-back detection of the two ionized electrons in the polarization ...


Imaging Electronic Motions By Ultrafast Electron Diraction, Hua-Chieh Shao, Anthony F. Starace 2017 University of Nebraska-Lincoln

Imaging Electronic Motions By Ultrafast Electron Diraction, Hua-Chieh Shao, Anthony F. Starace

Anthony F. Starace Publications

Recently ultrafast electron diraction and microscopy have reached unprecedented temporal resolution, and transient structures with atomic precision have been observed in various reactions. It is anticipated that these extraordinary advances will soon allow direct observation of electronic motions during chemical reactions. We therefore performed a series of theoretical investigations and simulations to investigate the imaging of electronic motions in atoms and molecules by ultrafast electron diraction. Three prototypical electronic motions were considered for hydrogen atoms. For the case of a breathing mode, the electron density expands and contracts periodically, and we show that the time-resolved scattering intensities re ect such ...


Energy-Resolved Coherent Diffraction From Laser-Driven Electronic Motion In Atoms, Hua-Chieh Shao, Anthony F. Starace 2017 University of Nebraska-Lincoln

Energy-Resolved Coherent Diffraction From Laser-Driven Electronic Motion In Atoms, Hua-Chieh Shao, Anthony F. Starace

Anthony F. Starace Publications

We investigate theoretically the use of energy-resolved ultrafast electron diffraction to image laser-driven electronic motion in atoms. A chirped laser pulse is used to transfer the valence electron of the lithium atom from the ground state to the first excited state. During this process, the electronic motion is imaged by 100-fs and 1-fs electron pulses in energy-resolved diffraction measurements. Simulations show that the angle-resolved spectra reveal the time evolution of the energy content and symmetry of the electronic state. The time-dependent diffraction patterns are further interpreted in terms of the momentum transfer. For the case of incident 1-fs electron pulses ...


Ionization Enhancement And Suppression By Phase-Locked Ultrafast Pulse Pairs, David B. Foote, Y. Lin, Liang-Wen Pi, Jean Marcel Ngoko Djiokap, Anthony F. Starace, W. T. Hill 2017 University of Maryland at College Park

Ionization Enhancement And Suppression By Phase-Locked Ultrafast Pulse Pairs, David B. Foote, Y. Lin, Liang-Wen Pi, Jean Marcel Ngoko Djiokap, Anthony F. Starace, W. T. Hill

Anthony F. Starace Publications

We present the results of a study of ionization of Xe atoms by a pair of phase-locked pulses, which is characterized by interference produced by the twin peaks. Two types of interference are considered: ordinary optical interference, which changes the intensity of the composite pulse and thus the ion yield, and a quantum interference, in which the excited electron wave packets interfere. We use the measured Xe+ yield as a function of the temporal delay and/or relative phase between the peaks to monitor the interferences and compare their relative strengths. We model the interference with a pulse intensity function ...


Adiabatic-Limit Coulomb Factors For Photoelectron And High-Order-Harmonic Spectra, M. V. Frolov, N. L. Manakov, A. A. Minina, S. V. Popruzhenko, Anthony F. Starace 2017 Voronezh State University, Russia

Adiabatic-Limit Coulomb Factors For Photoelectron And High-Order-Harmonic Spectra, M. V. Frolov, N. L. Manakov, A. A. Minina, S. V. Popruzhenko, Anthony F. Starace

Anthony F. Starace Publications

A momentum-dependent Coulomb factor in the probability for nonlinear ionization of atoms by a strong low-frequency laser field is calculated analytically in the adiabatic approximation. Expressions for this Coulomb factor, valid for an arbitrary laser pulse waveform, are obtained and analyzed in detail for the cases of linear and circular polarizations. The dependence of the Coulomb factor on the photoelectron momentum is shown to be significant in both cases. Using a similar technique, the Coulomb factor for emission of high-order harmonics by an atom in a bichromatic laser field is also calculated. In contrast to the case of a single-frequency ...


Thermomechanical Properties Of Aluminium Heaters To Test The Compact Muon Solenoid Cooling System For Phase Two Upgrade, Sandra Jimena González, Timothy Matthew Jones 2017 Universidad de Los Andes - Colombia

Thermomechanical Properties Of Aluminium Heaters To Test The Compact Muon Solenoid Cooling System For Phase Two Upgrade, Sandra Jimena González, Timothy Matthew Jones

The Summer Undergraduate Research Fellowship (SURF) Symposium

The main objectives of the Compact Muon Solenoid (CMS) experiment at the Large Hadron Collider are precision studies of the Standard Model of Particle Physics and the discovery of physics beyond it. To meet that, it is essential for the CMS detector to function at the highest efficiency for detecting subatomic particles within various technical constraints. In particular, the readout chips of the Pixel Tracker sub-detector produce significant heat and must be kept at -10 °C to ensure optimal performance and reduce cumulative damage in the high radiation environment. Thus, it is necessary to design a cooling system to extract ...


Machine Learning In Xenon1t Analysis, Dillon A. Davis, Rafael F. Lang, Darryl P. Masson 2017 Purdue University - North Central Campus

Machine Learning In Xenon1t Analysis, Dillon A. Davis, Rafael F. Lang, Darryl P. Masson

The Summer Undergraduate Research Fellowship (SURF) Symposium

In process of analyzing large amounts of quantitative data, it can be quite time consuming and challenging to uncover populations of interest contained amongst the background data. Therefore, the ability to partially automate the process while gaining additional insight into the interdependencies of key parameters via machine learning seems quite appealing. As of now, the primary means of reviewing the data is by manually plotting data in different parameter spaces to recognize key features, which is slow and error prone. In this experiment, many well-known machine learning algorithms were applied to a dataset to attempt to semi-automatically identify known populations ...


Kinematical Vortices In Double Photoionization Of Helium By Attosecond Pulses, Jean Marcel Ngoko Djiokap, A. V. Meremianin, N. L. Manakov, S. X. Hu, L. B. Madsen, Anthony F. Starace 2017 University of Nebraska-Lincoln

Kinematical Vortices In Double Photoionization Of Helium By Attosecond Pulses, Jean Marcel Ngoko Djiokap, A. V. Meremianin, N. L. Manakov, S. X. Hu, L. B. Madsen, Anthony F. Starace

Anthony F. Starace Publications

Two-armed helical vortex structures are predicted in the two-electron momentum distributions produced in double photoionization (DPI) of the He atom by a pair of time-delayed elliptically polarized attosecond pulses with opposite helicities. These predictions are based upon both a first-order perturbation theory analysis and numerical solutions of the two-electron, time-dependent Schrödinger equation in six spatial dimensions. The helical vortex structures originate from Ramsey interference of a pair of ionized two-electron wave packets, each having a total angular momentum of unity, and appear in the sixfold differential DPI probability distribution for any energy partitioning between the two electrons. The vortex structures ...


Cross Section And Transverse Single-Spin Asymmetry Of Muons From Open Heavy-Flavor Decays In Polarized P Plus P Collisions At Root S=200 Gev, C. Aidala, Nicole Apadula, Sarah C. Campbell, Lei Ding, John C. Hill, Nels J. Hotvedt, John G. Lajoie, Alexandre Lebedev, Craig Ogilvie, Milap R. Patel, Joshua Perry, Timothy T. Rinn, Marzia Rosati, Jonathan C. Runchey, Abhisek Sen, Alex Shaver, M. Shimomura, Arbin Timilsina, Shawn Douglas Whitaker, et al. 2017 University of Michigan

Cross Section And Transverse Single-Spin Asymmetry Of Muons From Open Heavy-Flavor Decays In Polarized P Plus P Collisions At Root S=200 Gev, C. Aidala, Nicole Apadula, Sarah C. Campbell, Lei Ding, John C. Hill, Nels J. Hotvedt, John G. Lajoie, Alexandre Lebedev, Craig Ogilvie, Milap R. Patel, Joshua Perry, Timothy T. Rinn, Marzia Rosati, Jonathan C. Runchey, Abhisek Sen, Alex Shaver, M. Shimomura, Arbin Timilsina, Shawn Douglas Whitaker, Et Al.

Craig Ogilvie

The cross section and transverse single-spin asymmetries of mu(-) and mu(+) from open heavy-flavor decays in polarized p + p collisions at root s = 200 GeV were measured by the PHENIX experiment during 2012 at the Relativistic Heavy Ion Collider. Because heavy-flavor production is dominated by gluon-gluon interactions at root s = 200 GeV, these measurements offer a unique opportunity to obtain information on the trigluon correlation functions. The measurements are performed at forward and backward rapidity (1.4 < vertical bar y vertical bar < 2.0) over the transverse momentum range of 1.25 < p(T) < 7 GeV/c for the cross ...


Higher-Twist Corrections To Gluon Tmd Factorization, I. Balitsky, A. Tarasov 2017 Old Dominion University

Higher-Twist Corrections To Gluon Tmd Factorization, I. Balitsky, A. Tarasov

Physics Faculty Publications

We calculate power corrections to TMD factorization for particle production by gluon-gluon fusion in hadron-hadron collisions.


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