ΠN And Strangeness Sigma Terms At The Physical Point With Chiral Fermions,
2016
University of Kentucky
ΠN And Strangeness Sigma Terms At The Physical Point With Chiral Fermions, Yi-Bo Yang, Andrei Alexandru, Terrence Draper, Jian Liang, Keh-Fei Liu
Physics and Astronomy Faculty Publications
Lattice QCD calculations with chiral fermions of the πN sigma term σπN and strangeness sigma term σπN including chiral interpolation with continuum and volume corrections are provided in this work, with the excited-state contaminations subtracted properly. We calculate the scalar matrix element for the light/strange quark directly and find σπN = 45.9(7.4)(2.8) MeV, with the disconnected insertion part contributing 20(12)(4)%, and σπN = 40.2(11.7)(3.5) MeV, which is somewhat smaller than σπN. The ratio of the strange/light scalar matrix elements is y = 0.09(3)(1).
Measurements Of DN2 And AN1: Probing The Neutron Spin Structure,
2016
Temple University
Measurements Of DN2 And AN1: Probing The Neutron Spin Structure, D. Flay, M. Posik, D. S. Parno, Kalyan C. Allada, W. R. Armstrong, T. Averett, F. Benmokhtar, W. Bertozzi, A. Camsonne, M. Canan, G. D. Cates, C. Chen, J. -P. Chen, S. Choi, E. Chudakov, F. Cusanno, M. M. Dalton, W. Deconinck, C. W. De Jager, X. Deng, A. Deur, Chiranjib Dutta, L. El Fassi, G. B. Franklin, M. Friend, H. Gao, F. Garibaldi, S. Gilad, R. Gilman, O. Glamazdin, Ameya Suresh Kolarkar, Wolfgang Korsch
Physics and Astronomy Faculty Publications
We report on the results of the E06-014 experiment performed at Jefferson Lab in Hall A, where a precision measurement of the twist-3 matrix element d2 of the neutron (dn2) was conducted. The quantity dn2 represents the average color Lorentz force a struck quark experiences in a deep inelastic electron scattering event off a neutron due to its interaction with the hadronizing remnants. This color force was determined from a linear combination of the third moments of the 3He spin structure functions, g1 and g2, after nuclear corrections had …
Protophobic Fifth-Force Interpretation Of The Observed Anomaly In 8Be Nuclear Transitions,
2016
University of California - Irvine
Protophobic Fifth-Force Interpretation Of The Observed Anomaly In 8Be Nuclear Transitions, Jonathan L. Feng, Bartosz Fornal, Iftah Galon, Susan Gardner, Jordan Smolinsky, Tim M. P. Tait, Philip Tanedo
Physics and Astronomy Faculty Publications
Recently a 6.8σ anomaly has been reported in the opening angle and invariant mass distributions of e+e− pairs produced in 8Be nuclear transitions. The data are explained by a 17 MeV vector gauge boson X that is produced in the decay of an excited state to the ground state, 8Be∗ → 8Be X, and then decays through X → e+e−. The X boson mediates a fifth force with a characteristic range of 12 fm and has millicharged couplings to up and down quarks and electrons, and a …
Two-Particle Correlation Studies In Heavy Ion Collisions At The Large Hadron Collider,
2016
Purdue University
Two-Particle Correlation Studies In Heavy Ion Collisions At The Large Hadron Collider, Lingshan Xu
Open Access Dissertations
Results on two-particle angular correlations in pPb at [square root sNN] =5.02 TeV and PbPb collisions at [square root sNN] =2.76 TeV are reported. The long-range correlations in pseudorapidity (“ridge'') has been seen in various systems, including PbPb, pPb and pp systems. In this thesis, two-particle correlations in pPb collisions at nucleon-nucleon center-of-mass energy of 5.02 TeV are studied as a function of the pseudorapidity separation (Δ η) of the particle pair at small azimuthal angle separation (|Δ&phis;| < π/3). The correlations are decomposed into a jet component that dominates the short-range correlations (|Δη| < 1), and a component that persists at large Δη, which is the ridge. The ridge may be associated with collective behavior of the produced system, well …
Measurement Of The Upsilon(Ns) Cross Section At Cdf,
2016
Purdue University
Measurement Of The Upsilon(Ns) Cross Section At Cdf, Michael D. Meier
Open Access Dissertations
Since the bound bb¯ system was first discovered, researchers have been trying to explain the production mechanism for quarkonium to learn more about this system. Several different theories try to describe quarkonium production, and while these theories agree with experimental measurements of production rates, theoretical predictions for quarkonium polarization vary. Careful measurement of the ϒ( nS) angular distribution along with the ϒ(nS) cross section can provide insight into the quarkonium production mechanism. This analysis measures the ϒ(nS) cross section and ϒ(1 S) polarization parameters.
Ultracold Quantum Scattering In The Presence Of Synthetic Spin-Orbit Coupling,
2016
Purdue University
Ultracold Quantum Scattering In The Presence Of Synthetic Spin-Orbit Coupling, Su-Ju Wang
Open Access Dissertations
Two-body scattering constitutes one of the most fundamental processes in various physical systems ranging from ultracold dilute quantum gases to energetic quark- gluon plasmas. In this dissertation, we study the low-energy atomic collision physics in the presence of synthetic gauge fields, which are generated by atom-light interaction. One category of synthetic gauge fields is the artificial spin-orbit coupling. We discuss three different aspects in scattering theory: ultracold collision, scattering resonance, and bound state formation from a few-body perspective when the atomic spin states are coupled with their center-of-mass motion. The understanding of the spin-orbit effects on the modification of the …
A Study Of The Radiative Pion Capture Process As A Background To The Search For Muon To Electron Conversion With The Mu2e Experiment.,
2016
University of Louisville
A Study Of The Radiative Pion Capture Process As A Background To The Search For Muon To Electron Conversion With The Mu2e Experiment., Jacob Colston
Electronic Theses and Dissertations
This thesis will introduce radiative pion capture (RPC), a process which can produce a fake signal in a search for the coherent conversion of a muon to an electron in the presence of a nucleus. There will be a brief introduction to standard model (SM) physics, as well as some more in-depth discussion of the relevant high energy physics at the Mu2e experiment. We will discuss charged lepton flavor violation (CLFV), as well as Supersymmetry, which predicts CLFV at higher intensities than the SM prediction. A description of the RPC process follows, including the external and internal conversions in pion …
Multistart Spiral Electron Vortices In Ionization By Circularly Polarized Uv Pulses,
2016
University of Nebraska-Lincoln
Multistart Spiral Electron Vortices In Ionization By Circularly Polarized Uv Pulses, Jean Marcel Ngoko Djiokap, Alexei V. Meremianin, N. L. Manakov, S. X. Hu, L. B. Madsen, Anthony F. Starace
Anthony F. Starace Publications
Multistart spiral vortex patterns are predicted for the electron momentum distributions in the polarization plane following ionization of the helium atom by two time-delayed circularly polarized ultrashort laser pulses. For two ultraviolet (UV) pulses having the same frequency (such that two photons are required for ionization), single-color two-photon interferometry with corotating or counter-rotating time-delayed pulses is found to lead respectively to zero-start or four-start spiral vortex patterns in the ionized electron momentum distributions in the polarization plane. In contrast, two-color one-photon plus two-photon interferometry with time-delayed corotating or counter-rotating UV pulses is found to lead respectively to one …
Uv Completions For Non-Critical Strings,
2016
CUNY Graduate Center
Uv Completions For Non-Critical Strings, Fabio Apruzzi, Falk Hassler, Jonathan J. Heckman, Ilarion V. Melnikov
Publications and Research
Compactifications of the physical superstring to two dimensions provide a general template for realizing 2D conformal field theories coupled to worldsheet gravity, i.e. non-critical string theories. Motivated by this observation, in this paper we determine the quasi-topological 8D theory which governs the vacua of 2D N = (0, 2) gauged linear sigma models (GLSMs) obtained from compactifications of type I and heterotic strings on a Calabi-Yau fourfold. We also determine the quasi-topological 6D theory governing the 2D vacua of intersecting 7-branes in compactifications of F-theory on an elliptically fibered Calabi-Yau fivefold, where matter fields and interaction terms localize on lower-dimensional …
New Prospects In Fixed Target Searches For Dark Forces With The Seaquest Experiment At Fermilab,
2016
University of Kentucky
New Prospects In Fixed Target Searches For Dark Forces With The Seaquest Experiment At Fermilab, Susan Gardner, R. J. Holt, A. S. Tadepalli
Physics and Astronomy Faculty Publications
An intense 120 GeV proton beam incident on an extremely long iron target generates enormous numbers of light-mass particles that also decay within that target. If one of these particles decays to a final state with a hidden gauge boson, or if such a particle is produced as a result of the initial collision, then that weakly interacting hidden-sector particle may traverse the remainder of the target and be detected downstream through its possible decay to an e+ e−, μ+ μ−, or π+ π− final state. These conditions can be realized through …
New Classical Solutions In Supergravity,
2016
CUNY Graduate Center
New Classical Solutions In Supergravity, Zhibai Zhang
Dissertations, Theses, and Capstone Projects
In this Ph.D. thesis we construct three classes of new solutions to supergravity theories in various dimensions and study their properties. The first class is reduction ansatz of 10D and 11D supergravity on Ricci-flat and noncompact manifolds. These reductions are from a scaling limit of the famous spherical reductions, and can be solely supported by warp factors. The second class contains a large number of String/M theory solutions that have Lifshitz or Schrodinger scaling symmetry, obtained from marginally deforming the geometry of internal dimensions of previous solutions. We propose that these new solutions are dual to marginal deformations of certain …
Bunch Splitting Simulations For The Jleic Ion Collider Ring,
2016
Old Dominion University
Bunch Splitting Simulations For The Jleic Ion Collider Ring, R. Gamage, T. Satogata
Physics Faculty Publications
We describe the bunch splitting strategies for the proposed JLEIC ion collider ring at Jefferson Lab. This complex requires an unprecedented 9:6832 bunch splitting, performed in several stages. We outline the problem and current results, optimized with ESME including general parameterization of 1:2 bunch splitting for JLEIC parameters.
Cpt, Cp, And C Transformations Of Fermions, And Their Consequences, In Theories With B − L Violation,
2016
University of Kentucky
Cpt, Cp, And C Transformations Of Fermions, And Their Consequences, In Theories With B − L Violation, Susan Gardner, Xinshuai Yan
Physics and Astronomy Faculty Publications
We consider the transformation properties of fermions under the discrete symmetries CPT, CP, and C in the presence of B − L violation. We thus generalize the analysis of the known properties of Majorana neutrinos, probed via neutrinoless double beta decay, to include the case of Dirac fermions with B − L violation, which can be probed via neutron-antineutron oscillations. We show that the resulting CPT phase has implications for the interplay of neutron-antineutron oscillations with external fields and sources and consider the differences in the Majorana dynamics of neutrinos and neutrons in the context of theories with …
An Apparatus For Studying Electrical Breakdown In Liquid Helium At 0.4 K And Testing Electrode Materials For The Neutron Electric Dipole Moment Experiment At The Spallation Neutron Source,
2016
Los Alamos National Laboratory
An Apparatus For Studying Electrical Breakdown In Liquid Helium At 0.4 K And Testing Electrode Materials For The Neutron Electric Dipole Moment Experiment At The Spallation Neutron Source, T. M. Ito, J. C. Ramsey, W. Yao, D. H. Beck, V. Cianciolo, S. M. Clayton, Christopher B. Crawford, S. A. Currie, B. W. Filippone, W. C. Griffith, M. Makela, R. Schmid, G. M. Seidel, Z. Tang, D. Wagner, W. Wei, S. E. Williamson
Physics and Astronomy Faculty Publications
We have constructed an apparatus to study DC electrical breakdown in liquid helium at temperatures as low as 0.4 K and at pressures between the saturated vapor pressure and ∼600 Torr. The apparatus can house a set of electrodes that are 12 cm in diameter with a gap of 1–2 cm between them, and a potential up to ±50 kV can be applied to each electrode. Initial results demonstrated that it is possible to apply fields exceeding 100 kV/cm in a 1 cm gap between two electropolished stainless steel electrodes 12 cm in diameter for a wide range of pressures …
Using Precise Measurements Of Muon G-2 To Constrain New Physics,
2016
Otterbein University
Using Precise Measurements Of Muon G-2 To Constrain New Physics, Evan M. Heintz
Undergraduate Honors Thesis Projects
We study the contributions to the anomalous magnetic moment of the muon from theories beyond the Standard Model, specifically supersymmetry. Results found at Brookhaven National Laboratory in 2001 during the E821 experiment indicate that current theories may not fully account for all of the interactions between the muon and fundamental gauge bosons. We re-derive Dirac's famous result of g=2. We then reproduce the one loop contributions from electroweak theory to the anomalous magnetic moment of the muon. We then use these calculations as a template for theories that go beyond the Standard Model. We show illustrative results for minimal supersymmetry …
Cebaf Upgrade Bunch Length Measurements,
2016
Old Dominion University
Cebaf Upgrade Bunch Length Measurements, Mahmoud Mohamad Ali Ahmad
Physics Theses & Dissertations
Many accelerators use short electron bunches and measuring the bunch length is important for efficient operations. CEBAF needs a suitable bunch length because bunches that are too long will result in beam interruption to the halls due to excessive energy spread and beam loss. In this work, bunch length is measured by invasive and non-invasive techniques at different beam energies. Two new measurement techniques have been commissioned; a harmonic cavity showed good results compared to expectations from simulation, and a real time interferometer is commissioned and first checkouts were performed. Three other techniques were used for measurements and comparison purposes …
Narrow Nucleon-Ψ(2S) Bound State And Lhcb Pentaquarks,
2016
University of Kentucky
Narrow Nucleon-Ψ(2S) Bound State And Lhcb Pentaquarks, Michael I. Eides, Victor Yu. Petrov, Maxim V. Polyakov
Physics and Astronomy Faculty Publications
We interpret the newly discovered pentaquark Pc(4450) as a bound state of charmonium ψ(2S) and the nucleon. The binding potential is due to the charmonium-nucleon interaction that in the heavy quark approximation is proportional to the product of the charmonium chromoelectric polarizability and the nucleon energy-momentum distribution. We use the large Nc expansion to estimate the quarkonium polarizability and calculate the nucleon properties in the framework of the mean-field picture of light baryons. Two almost degenerate states JP=(1/2)− and JP=(3/2)− are predicted at the position of the Pc …
Atomic Photoionization Experiment By Harmonic-Generation Spectroscopy,
2016
Voronezh State University, Russia
Atomic Photoionization Experiment By Harmonic-Generation Spectroscopy, M. V. Frolov, T. S. Sarantseva, N. L. Manakov, K. D. Fulfer, B. P. Wilson, J. Troß, X. Ren, Erwin D. Poliakoff, A. A. Silaev, N. V. Vvedenskii, Anthony F. Starace, C. A. Trallero-Herrero
Anthony F. Starace Publications
Measurements of the high-order-harmonic generation yield of the argon (Ar) atom driven by a strong elliptically polarized laser field are shown to completely determine the field-free differential photoionization cross section of Ar, i.e., the energy dependence of both the angle-integrated photoionization cross section and the angular distribution asymmetry parameter.
Orbital Angular Momentum And Generalized Transverse Momentum Distribution,
2016
University of Maryland
Orbital Angular Momentum And Generalized Transverse Momentum Distribution, Yong Zhao, Keh-Fei Liu, Yi-Bo Yang
Physics and Astronomy Faculty Publications
We show that, when boosted to the infinite momentum frame, the quark and gluon orbital angular momentum operators defined in the nucleon spin sum rule of Chen et al. are the same as those whose matrix elements correspond to the moments of generalized transverse momentum distributions. This completes the connection between the infinite momentum limit of each term in that sum rule and experimentally measurable observables. We also show that these orbital angular momentum operators can be defined locally and discuss the strategies of calculating them in lattice QCD.
Control Of Threshold Enhancements In Harmonic Generation By Atoms In A Two-Color Laser Field With Orthogonal Polarizations,
2016
Voronezh State University, Russia
Control Of Threshold Enhancements In Harmonic Generation By Atoms In A Two-Color Laser Field With Orthogonal Polarizations, M. V. Frolov, N. L. Manakov, T. S. Sarantseva, A. A. Silaev, N. V. Vvedenskii, Anthony F. Starace
Anthony F. Starace Publications
Threshold phenomena (or channel-closing effects) are analyzed in high-order harmonic generation (HHG) by atoms in a two-color laser field with orthogonal linearly polarized components of a fundamental field and its second harmonic. We show that the threshold behavior of HHG rates for the case of a weak second harmonic component is sensitive to the parity of a closing multiphoton ionization channel and the spatial symmetry of the initial bound state of the target atom, while for the case of comparable intensities of both components, suppression of threshold phenomena is observed as the relative phase between the components of a two-color …
