Open Access. Powered by Scholars. Published by Universities.®
- Institution
- Keyword
-
- Accelerator technology (2)
- Cavity (2)
- D-branes (2)
- Niobium (2)
- Parton distributions (2)
-
- Physics (2)
- QCD (2)
- Radio-frequency (2)
- SRF (2)
- Scattering (2)
- Superconducting RF (2)
- Accelerating-gradient (1)
- Asymptotics (1)
- Automation (1)
- BPS black hole microstates (1)
- Baseline design (1)
- Beam dynamics (1)
- Beam target double spin asymmetries (1)
- Behavior (1)
- Biconformal (1)
- Black holes (1)
- Bose-einstein (1)
- Boundary conditions (1)
- Brane dynamics in gauge theories (1)
- Bremsstrahlung (1)
- CLAS (1)
- Cavity resonators (1)
- Circular dichroism (1)
- Collisions (1)
- Conformal gravity (1)
Articles 1 - 30 of 34
Full-Text Articles in Physics
Boundary Conditions As Dynamical Fields, V. Parameswaran Nair, Dimitra Karabali
Boundary Conditions As Dynamical Fields, V. Parameswaran Nair, Dimitra Karabali
Publications and Research
The possibility of treating boundary conditions in terms of a bilocal dynamical field is formalized in terms of a boundary action. This allows for a simple path-integral perturbation theory approach to physical effects such as radiation from a time-dependent boundary. The nature of the action which governs the dynamics of the bilocal field is investigated for a limited case (which includes the Robin boundary conditions).
D-Brane Instantons As Gauge Instantons In Orientifolds Of Chiral Quiver Theories, Sebastian Franco, Ander Retolaza, Angel Uranga
D-Brane Instantons As Gauge Instantons In Orientifolds Of Chiral Quiver Theories, Sebastian Franco, Ander Retolaza, Angel Uranga
Publications and Research
Systems of D3-branes at orientifold singularities can receive non-perturbative D-brane instanton corrections, inducing field theory operators in the 4d effective theory. In certain non-chiral examples, these systems have been realized as the infrared end point of a Seiberg duality cascade, in which the D-brane instanton effects arise from strong gauge theory dynamics. We present the rst UV duality cascade completion of chiral D3-brane theories, in which the D-brane instantons arise from gauge theory dynamics. Chiral examples are interesting because the instanton fermion zero mode sector is topologically protected, and therefore lead to more robust setups. As an application of our …
Do All Bps Black Hole Microstates Carry Zero Angular Momentum?, Abishek Chowdhury, Richard S. Garavuso, Swapnamay Mondal, Ashoke Sen
Do All Bps Black Hole Microstates Carry Zero Angular Momentum?, Abishek Chowdhury, Richard S. Garavuso, Swapnamay Mondal, Ashoke Sen
Publications and Research
From the analysis of the near horizon geometry and supersymmetry algebra it has been argued that all the microstates of single centered BPS black holes with four unbroken supersymmetries carry zero angular momentum in the region of the moduli space where the black hole description is valid. A stronger form of the conjecture would be that the result holds for any sufficiently generic point in the moduli space. In this paper we set out to test this conjecture for a class of black hole microstates in type II string theory on T6 , represented by four stacks of D-branes wrapped …
Distributions Of Long-Lived Radioactive Nuclei Provided By Star-Forming Environments, Marco Fatuzzo, Fred Adams
Distributions Of Long-Lived Radioactive Nuclei Provided By Star-Forming Environments, Marco Fatuzzo, Fred Adams
Faculty Scholarship
Radioactive nuclei play an important role in planetary evolution by providing an internal heat source, which affects planetary structure and helps facilitate plate tectonics. A minimum level of nuclear activity is thought to be necessary—but not sufficient—for planets to be habitable. Extending previous work that focused on short-lived nuclei, this paper considers the delivery of long-lived radioactive nuclei to circumstellar disks in star forming regions. Although the long-lived nuclear species are always present, their abundances can be enhanced through multiple mechanisms. Most stars form in embedded cluster environments, so that disks can be enriched directly by intercepting ejecta from supernovae …
2d (0,2) Quiver Gauge Theories And D-Branes, Sebastian Franco, Dongwook Ghim, Sangmin Lee, Rak-Kyeong Seong, Daisuke Yokoyama
2d (0,2) Quiver Gauge Theories And D-Branes, Sebastian Franco, Dongwook Ghim, Sangmin Lee, Rak-Kyeong Seong, Daisuke Yokoyama
Publications and Research
We initiate a systematic study of 2d(0,2) quiver gauge theories on the world-volume of D1-branes probing singular toric Calabi-Yau 4-folds. We present an algorithm for efficiently calculating the classical mesonic moduli spaces of these theories, which cor-respond to the probed geometries. We also introduce a systematic procedure for constructing the gauge theories for arbitrary toric singularities by means of partial resolution, which translates to higgsing in the field theory. Finally, we introduce Brane Brick Models, a novel class of brane configurations that consist of D4-branes suspended from an NS5-brane wrap-ping a holomorphic surface, tessellating a 3-torus. Brane Brick Models are …
Electron Vortices In Photoionization By Circularly Polarized Attosecond Pulses, Jean Marcel Ngoko Djiokap, S. X. Hu, L. B. Madsen, N. L. Manakov, A. V. Meremianin, Anthony F. Starace
Electron Vortices In Photoionization By Circularly Polarized Attosecond Pulses, Jean Marcel Ngoko Djiokap, S. X. Hu, L. B. Madsen, N. L. Manakov, A. V. Meremianin, Anthony F. Starace
Anthony F. Starace Publications
Single ionization of He by two oppositely circularly polarized, time-delayed attosecond pulses is shown to produce photoelectron momentum distributions in the polarization plane having helical vortex structures sensitive to the time delay between the pulses, their relative phase, and their handedness. Results are obtained by both ab initio numerical solution of the two-electron time-dependent Schrödinger equation and by a lowest-order perturbation theory analysis. The energy, bandwidth, and temporal duration of attosecond pulses are ideal for observing these vortex patterns.
Scaling Laws For High-Order-Harmonic Generation With Midinfrared Laser Pulses, M. V. Frolov, N. L. Manakov, Wei-Hao Xiong, Liang-You Peng, J. Burgdörfer, Anthony F. Starace
Scaling Laws For High-Order-Harmonic Generation With Midinfrared Laser Pulses, M. V. Frolov, N. L. Manakov, Wei-Hao Xiong, Liang-You Peng, J. Burgdörfer, Anthony F. Starace
Anthony F. Starace Publications
We derive an analytic expression for thewavelength scaling of the high-order-harmonic generation (HHG) yield induced by midinfrared driving laser fields. It is based on a quasiclassical description of the returning electron wave packet, which is shown to be largely independent of atomic properties. The accuracy of this analytic expression is confirmed by comparison with results of numerical solutions of the time-dependent Schr¨odinger equation for wavelengths in the range of 1.4 μm ≤ λ ≤ 4 μm. We verify the wavelength scaling of the HHG yield found numerically for midinfrared laser fields in a recent paper by Le et al. [
Favorable Target Positions For Intense Laser Acceleration Of Electrons In Hydrogen-Like, Highly-Charged Ions, Liang-Wen Pi, S. X. Hu, Anthony F. Starace
Favorable Target Positions For Intense Laser Acceleration Of Electrons In Hydrogen-Like, Highly-Charged Ions, Liang-Wen Pi, S. X. Hu, Anthony F. Starace
Anthony F. Starace Publications
Classical relativistic Monte Carlo simulations of petawatt laser acceleration of electrons bound initially in hydrogen-like, highly-charged ions show that both the angles and energies of the laser-accelerated electrons depend on the initial ion positions with respect to the laser focus. Electrons bound in ions located after the laser focus generally acquire higher (≈GeV) energies and are ejected at smaller angles with respect to the laser beam. Our simulations assume a tightly-focused linearly-polarized laser pulse with intensity approaching 1022W/cm2. Up to fifth order corrections to the paraxial approximation of the laser field in the focal region are …
Photodetachment Of A Model Molecular System By An Elliptically Polarized Field, M. V. Frolov, N. L. Manakov, S. S. Marmo, Anthony F. Starace
Photodetachment Of A Model Molecular System By An Elliptically Polarized Field, M. V. Frolov, N. L. Manakov, S. S. Marmo, Anthony F. Starace
Anthony F. Starace Publications
The differential cross section for one-photon molecular detachment by an elliptically polarized field is analyzed for a one-electron molecular model comprised of an electron in the field of two (generally nonequivalent) attractive zero-range potentials (ZRPs) separated by the distance R. A phenomenological parametrization of the photodetachment cross section for a fixed-in-space molecular system in terms of two scalar dynamical parameters is presented and circular dichroism effects are discussed. Analytic results for the dynamical molecular parameters within the ZRP molecular model are used to analyze interference phenomena (including two-center interference) and dichroic effects in the detached electron angular distributions and …
Singly-Spinning Black Rings Ind= 5 U(1)3 Supergravity, H. Lu, C. N. Pope, Justin F. Vázquez-Poritz, Zhibai Zhang
Singly-Spinning Black Rings Ind= 5 U(1)3 Supergravity, H. Lu, C. N. Pope, Justin F. Vázquez-Poritz, Zhibai Zhang
Publications and Research
We construct black ring solutions in five-dimensional U(1)3supergravity which carry three dipole charges, three electric charges and one angular momentum parameter.These solutions are written in a form that is sufficiently compact that their global and thermodynamic properties can be studied explicitly. In particular, we find that the Smarrformula is obeyed regardless of whether or not conical singularities are present, where as the first law of thermodynamics holds only in the absence of conical singularities. We also present black ring solutions with three background magnetic fields.
Rescattering Effects In Laser-Assisted Electron-Atom Bremsstrahlung, A. N. Zheltukhin, A. V. Flegel, M. V. Frolov, N. L. Manakov, Anthony F. Starace
Rescattering Effects In Laser-Assisted Electron-Atom Bremsstrahlung, A. N. Zheltukhin, A. V. Flegel, M. V. Frolov, N. L. Manakov, Anthony F. Starace
Anthony F. Starace Publications
Rescattering effects in non-resonant spontaneous laser-assisted electron–atom bremsstrahlung (LABrS) are analyzed within the framework of time-dependent effective-range (TDER) theory. It is shown that high energy LABrS spectra exhibit rescattering plateau structures that are similar to those that are well-known in strong field laser-induced processes as well as those that have been predicted theoretically in laser-assisted collision processes. In the limit of a low-frequency laser field, an analytic description of LABrS is obtained from a rigorous quantum analysis of the exact TDER results for the LABrS amplitude. This amplitude is represented as a sum of factorized terms involving three factors, each …
Geometrization Conditions For Perfect Fluids, Scalar Fields, And Electromagnetic Fields, Charles G. Torre, Dionisios Krongos
Geometrization Conditions For Perfect Fluids, Scalar Fields, And Electromagnetic Fields, Charles G. Torre, Dionisios Krongos
Presentations and Publications
Rainich-type conditions giving a spacetime “geometrization” of matter fields in general relativity are reviewed and extended. Three types of matter are considered: perfect fluids, scalar fields, and elec- tromagnetic fields. Necessary and sufficient conditions on a spacetime metric for it to be part of a perfect fluid solution of the Einstein equa- tions are given. Formulas for constructing the fluid from the metric are obtained. All fluid results hold for any spacetime dimension. Ge- ometric conditions on a metric which are necessary and sufficient for it to define a solution of the Einstein-scalar field equations and for- mulas for constructing …
Variation Of The Linear Biconformal Action, James Thomas Wheeler
Variation Of The Linear Biconformal Action, James Thomas Wheeler
All Physics Faculty Publications
We find the field equations of biconformal space in a basis adapted to Lagrangian submanifolds on which the restriction of the Killing metric is non-degenerate.
Studies In Torsion Free Biconformal Spaces. Case 2: \Gamma_{-} = 0, James Thomas Wheeler
Studies In Torsion Free Biconformal Spaces. Case 2: \Gamma_{-} = 0, James Thomas Wheeler
All Physics Faculty Publications
We show that the solutions for the symmetric part of the connection in homogeneous biconformal space also satisfy the more general field equations of curved biconformal spaces in the case when \gamma_{-} = 0.
Studies In Torsion Free Biconformal Spaces, James Thomas Wheeler
Studies In Torsion Free Biconformal Spaces, James Thomas Wheeler
All Physics Faculty Publications
We study whether the solutions for the symmetric part of the connection in homogeneous biconformal space also satisfy the more general field equation of curved biconformal spaces. We show that the six field equations for the torsion and co-torsion are satisfied by vanishing torsion together with the Lorentzian form of the metric when γ+ = 0.
Charged Particle Dynamics In The Magnetic Field Of A Long Straight Current-Carrying Wire, M. Fatuzzo, A. Prentice, T. Toepker
Charged Particle Dynamics In The Magnetic Field Of A Long Straight Current-Carrying Wire, M. Fatuzzo, A. Prentice, T. Toepker
Faculty Scholarship
The article discusses the concept behind motion of a charged particle in a non-uniform filed of a wire carrying current. Topics discussed include possible types of motion in a current carrying field, vector analysis of velocity and magnetic field of the particle and Coupled differential equations.
Effects Of Crab Cavities Multipole Content In An Electron-Ion Collider, A. Castilla, V. S. Morozov, T. Satogata, J. R. Delayen
Effects Of Crab Cavities Multipole Content In An Electron-Ion Collider, A. Castilla, V. S. Morozov, T. Satogata, J. R. Delayen
Physics Faculty Publications
The impact on the beam dynamics of the Medium Energy Electron-Ion Colider (MEIC) due to the multipole content of the 750 MHz crab cavity was studied using thin multipole elements for 6D phase space particle tracking in ELEGANT. Target values of the sextupole component for the cavity’s field expansion were used to perform preliminary studies on the proton beam stability when compared to the case of pure dipole content of the rf kicks. Finally, important effects on the beam sizes due to non-linear components of the crab cavities’ fields were identified and some criteria for their future study were proposed.
Temperature Mapping Of Nitrogen-Doped Niobium Superconducting Radiofrequency Cavities, Junki Makita, Gianluigi Ciovati, Pashupati Dhakal
Temperature Mapping Of Nitrogen-Doped Niobium Superconducting Radiofrequency Cavities, Junki Makita, Gianluigi Ciovati, Pashupati Dhakal
Physics Faculty Publications
It was recently shown that diffusing nitrogen on the inner surface of superconducting radiofrequency (SRF) cavities at high temperature can improve the quality factor of the niobium cavity. However, a reduction of the quench field is also typically found. To better understand the location of rf losses and quench, we used a thermometry system to map the temperature of the outer surface of ingot Nb cavities after nitrogen doping and electropolishing. Surface temperature of the cavities was recorded while increasing the rf power and also during the quenching. The results of thermal mapping showed no precursor heating on the cavities …
Rapidity Evolution Of Gluon Tmd From Low To Moderate X, I. Balitsky, A. Tarasov
Rapidity Evolution Of Gluon Tmd From Low To Moderate X, I. Balitsky, A. Tarasov
Physics Faculty Publications
We study how the rapidity evolution of gluon transverse momentum dependent distribution changes from nonlinear evolution at small x << 1 to linear evolution at moderate x ∼ 1.
The Heavy Photon Search Test Detector, M. Battaglieri, S. Boyarinov, S. Bueltmann, V. Burkert, A. Celentano, G. Charles, W. Cooper, C. Cuevas, N. Dashyan, R. Devita, L. B. Weinstein
The Heavy Photon Search Test Detector, M. Battaglieri, S. Boyarinov, S. Bueltmann, V. Burkert, A. Celentano, G. Charles, W. Cooper, C. Cuevas, N. Dashyan, R. Devita, L. B. Weinstein
Physics Faculty Publications
The Heavy Photon Search (HPS), an experiment to search for a hidden sector photon in fixed target electroproduction, is preparing for installation at the Thomas Jefferson National Accelerator Facility (JLab) in the Fall of 2014. As the first stage of this project, the HPS Test Run apparatus was constructed and operated in 2012 to demonstrate the experiment׳s technical feasibility and to confirm that the trigger rates and occupancies are as expected. This paper describes the HPS Test Run apparatus and readout electronics and its performance. In this setting, a heavy photon can be identified as a narrow peak in the …
Double Spin Asymmetries Of Inclusive Hadron Electroproduction From A Transversely Polarized He-3 Target, Y. X. Zhao, K. Allada, K. Aniol, J.R.M. Annand, T. Averett, F. Benmokhtar, M. Canan
Double Spin Asymmetries Of Inclusive Hadron Electroproduction From A Transversely Polarized He-3 Target, Y. X. Zhao, K. Allada, K. Aniol, J.R.M. Annand, T. Averett, F. Benmokhtar, M. Canan
Physics Faculty Publications
We report the measurement of beam-target double spin asymmetries (ALT) in the inclusive production of identified hadrons, →e + 3He↑ → h + X, using a longitudinally polarized 5.9-GeV electron beam and a transversely polarized 3He target. Hadrons (π±, K±, and proton) were detected at 16 ° with an average momentum ( Ph ) = 2.35 GeV/c and a transverse momentum (pT) coverage from 0.60 to 0.68 GeV/c. Asymmetries from the He-3 target were observed to be nonzero for π± production when the target was polarized …
Nitrogen Doping Study In Ingot Niobium Cavities, Pashupati Dhakal, Gianluigi Ciovati, Peter Kneisel, Ganapati Rao Myneni, Junki Makita
Nitrogen Doping Study In Ingot Niobium Cavities, Pashupati Dhakal, Gianluigi Ciovati, Peter Kneisel, Ganapati Rao Myneni, Junki Makita
Physics Faculty Publications
Thermal diffusion of nitrogen in superconducting radio frequency cavities at temperatures around 800C has resulted in the increase in quality factor with a low-field Q-rise. However, the maximum accelerating gradients of these doped cavities often reduces below the values achieved by standard treatments. In this contribution, we present the results of the nitrogen diffusion into ingot niobium cavities subjected to successive material removal from the inner cavity surface by electropolishing in an effort to explore the underlying cause for the gradient degradation.
Measurements Of Ep → E'Π+N At 1.6 < W <2.0 Gev And Extraction Of Nucleon Resonance Electrocouplings At Clas, The Clas Collaboration, K. Park, K. P. Adhikari, M. J. Amaryan, L. El Fassi, Y. Prok, L. B. Weinstein
Measurements Of Ep → E'Π+N At 1.6 < W <2.0 Gev And Extraction Of Nucleon Resonance Electrocouplings At Clas, The Clas Collaboration, K. Park, K. P. Adhikari, M. J. Amaryan, L. El Fassi, Y. Prok, L. B. Weinstein
Physics Faculty Publications
Differential cross sections of the exclusive process ep -> e 'π+n were measured with good precision in the range of the photon virtuality Q2 = 1.8-4.5 GeV2 and the invariant mass range of the π+n final state W = 1.6-2.0 GeV using the Continuous Electron Beam Accelerator Facility Large Acceptance Spectrometer. Data were collected with nearly complete coverage in the azimuthal and polar angles of the n π+center-of-mass system. More than 37 000 cross-section points were measured. The contributions of the isospin I = ½ resonances N(1675) 5/2-, N(1680) 5/2 …
Towards A Resolution Of The Proton Form Factor Problem: New Electron And Positron Scattering Data, Clas Collaboration, D. Adikaram, L. B. Weinstein, R. P. Bennett, K. P, Adhikari, M. J. Amaryan, S. Careccia, L. El Fassi, C. E. Hyde, A. Klein, S E. Kuhn, M. Mayer, Z. W. Zhao
Towards A Resolution Of The Proton Form Factor Problem: New Electron And Positron Scattering Data, Clas Collaboration, D. Adikaram, L. B. Weinstein, R. P. Bennett, K. P, Adhikari, M. J. Amaryan, S. Careccia, L. El Fassi, C. E. Hyde, A. Klein, S E. Kuhn, M. Mayer, Z. W. Zhao
Physics Faculty Publications
There is a significant discrepancy between the values of the proton electric form factor, GpE, extracted using unpolarized and polarized electron scattering. Calculations predict that small two-photon exchange (TPE) contributions can significantly affect the extraction of GpEfrom the unpolarized electron-proton cross sections. We determined the TPE contribution by measuring the ratio of positron-proton to electron-proton elastic scattering cross sections using a simultaneous, tertiary electron-positron beam incident on a liquid hydrogen target and detecting the scattered particles in the Jefferson Lab CLAS detector. This novel technique allowed us to cover a wide range in virtual …
Progress On The Design Of The Polarized Medium Energy Electron Ion Collider At Jlab, F. Lin, S. A. Bogacz, P. D. Brindza, A Camsonne, E. Daly, Y. S. Derbenev, D. Douglas, R. Ent, D. Gaskell, R. L. Geng, A. Castilla, J. R. Delayen, C. E. Hyde, K. Park
Progress On The Design Of The Polarized Medium Energy Electron Ion Collider At Jlab, F. Lin, S. A. Bogacz, P. D. Brindza, A Camsonne, E. Daly, Y. S. Derbenev, D. Douglas, R. Ent, D. Gaskell, R. L. Geng, A. Castilla, J. R. Delayen, C. E. Hyde, K. Park
Physics Faculty Publications
The Medium-energy Electron Ion Collider (MEIC) at JLab is designed to provide high luminosity and high polarization needed to reach new frontiers in the exploration of nuclear structure. The luminosity, exceeding 1033 cm-2s−1 in a broad range of the center-of-mass (CM) energy and maximum luminosity above 1034 cm-2s−1, is achieved by high-rate collisions of short small-emittance low-charge bunches made possible by high-energy electron cooling of the ion beam and synchrotron radiation damping of the electron beam. The polarization of light ion species (p, d, 3He) can be easily preserved and …
Beam-Energy-Dependent Two-Pion Interferometry And The Freeze-Out Eccentricity Of Pions Measured In Heavy Ion Collisions At The Star Detector, L. Adamczyk, J.K. Adkins, G. Agakishiev, M.M. Aggarwal, Z. Ahammed, I. Koralt, Star Collaboration
Beam-Energy-Dependent Two-Pion Interferometry And The Freeze-Out Eccentricity Of Pions Measured In Heavy Ion Collisions At The Star Detector, L. Adamczyk, J.K. Adkins, G. Agakishiev, M.M. Aggarwal, Z. Ahammed, I. Koralt, Star Collaboration
Physics Faculty Publications
We present results of analyses of two-pion interferometry in Au + Au collisions at root s(NN) = 7.7, 11.5, 19.6, 27, 39, 62.4, and 200 GeV measured in the STAR detector as part of the BNL Relativistic Heavy Ion Collider Beam Energy Scan program. The extracted correlation lengths (Hanbury-Brown-Twiss radii) are studied as a function of beam energy, azimuthal angle relative to the reaction plane, centrality, and transverse mass (m(T)) of the particles. The azimuthal analysis allows extraction of the eccentricity of the entire fireball at kinetic freeze-out. The energy dependence of this observable is expected to be sensitive to …
Precision Measurements Of Aⁿ1 In The Deep Inelastic Regime, D. S. Parno, D. Flay, M. Posik, M. Canan, C. Hyde, The Jefferson Lab Hall A Collaboration
Precision Measurements Of Aⁿ1 In The Deep Inelastic Regime, D. S. Parno, D. Flay, M. Posik, M. Canan, C. Hyde, The Jefferson Lab Hall A Collaboration
Physics Faculty Publications
We have performed precision measurements of the double-spin virtual-photon asymmetry A1 on the neutron in the deep inelastic scattering regime, using an open-geometry, large-acceptance spectrometer and a longitudinally and transversely polarized 3He target. Our data cover a wide kinematic range 0.277 <= x <= 0.548 at an average Q2 value of 3.078(GeV/c)2, doubling the available high-precision neutron data in this xrange. We have combined our results with world data on proton targets to make a leading-order extraction of the ratio of polarized-to-unpolarized parton distribution functions for up quarks and for down quarks in the same kinematic range. Our data are consistent with …
Cross Sections For The Exclusive Photon Electroproduction On The Proton And Generalized Parton Distributions, H. S. Jo, D. Adikaram, M. J. Amaryan, L. El Fassi, N. Guler, A. Klein, S E. Kuhn, Y. Prok, L. B. Weinstein, J. Zhang, Z. W. Zhao
Cross Sections For The Exclusive Photon Electroproduction On The Proton And Generalized Parton Distributions, H. S. Jo, D. Adikaram, M. J. Amaryan, L. El Fassi, N. Guler, A. Klein, S E. Kuhn, Y. Prok, L. B. Weinstein, J. Zhang, Z. W. Zhao
Physics Faculty Publications
Unpolarized and beam-polarized fourfold cross sections (d4σ/dQ2dxBdtdϕ) for the ep → e'p'γ reaction were measured using the CLAS detector and the 5.75-GeV polarized electron beam of the Jefferson Lab accelerator, for 110 (Q2;xB;t) bins over the widest phase space ever explored in the valence-quark region. Several models of generalized parton distributions (GPDs) describe the data well at most of our kinematics. This increases our confidence that we understand the GPD H, expected to be the dominant contributor to these observables. Through a leading-twist …
Direct Observation Of Quark-Hadron Duality In The Free Neutron F2 Structure Function, I. Niculescu, G. Niculescu, W. Melnitchouk, J. Arrington, M. E. Christy, S. Kuhn
Direct Observation Of Quark-Hadron Duality In The Free Neutron F2 Structure Function, I. Niculescu, G. Niculescu, W. Melnitchouk, J. Arrington, M. E. Christy, S. Kuhn
Physics Faculty Publications
Using the recently published data from the BONuS(Barely Off-shell Nucleon Structure) experiment at Jefferson Lab, which utilized a spectator tagging technique to extract the inclusive electron-free neutron scattering cross section, we obtain the first direct observation of quark-hadron duality in the neutron F2 structure function. The data are used to reconstruct the lowest few (N = 2, 4, and 6) moments of F2 in the three prominent nucleon resonance regions, as well as the moments integrated over the entire resonance region. Comparison with moments computed from global parametrizations of parton distribution functions suggest that quark-hadron duality holds locally …
Precise Determination Of The Deuteron Spin Structure At Low To Moderate Q² With Clas And Extraction Of The Neutron Contribution, The Clas Collaboration, N. Guler, S E. Kuhn, Y. Prok, K. P. Adhikari, D. Adikaram, M. J. Amaryan, L. El Fassi, C. E. Hyde, A. Klein, L. B. Weinstein, Z. W. Zhao
Precise Determination Of The Deuteron Spin Structure At Low To Moderate Q² With Clas And Extraction Of The Neutron Contribution, The Clas Collaboration, N. Guler, S E. Kuhn, Y. Prok, K. P. Adhikari, D. Adikaram, M. J. Amaryan, L. El Fassi, C. E. Hyde, A. Klein, L. B. Weinstein, Z. W. Zhao
Physics Faculty Publications
We present the final results for the deuteron spin structure functions obtained from the full data set collected in 2000–2001 with Jefferson Lab's continuous electron beam accelerator facility (CEBAF) using the CEBAF large acceptance spectrometer (CLAS). Polarized electrons with energies of 1.6, 2.5, 4.2, and 5.8 GeV were scattered from deuteron (15ND3 ) targets, dynamically polarized along the beam direction, and detected with CLAS. From the measured double-spin asymmetry, the virtual photon absorption asymmetry Ad1 and the polarized structure function gd1 were extracted over a wide kinematic range (0.05GeV2 < Q2 < 5GeV2 and 0.9 …