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Old Dominion University

Scattering

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Full-Text Articles in Physical Sciences and Mathematics

Two-Current Transition Amplitudes With Two-Body Final States, Keegan H. Sherman, Feliipe G. Ortega-Gama, Raúl A. Briceño, Andrew W. Jackura Jun 2022

Two-Current Transition Amplitudes With Two-Body Final States, Keegan H. Sherman, Feliipe G. Ortega-Gama, Raúl A. Briceño, Andrew W. Jackura

Physics Faculty Publications

We derive the on-shell form of amplitudes containing two external currents with a single hadron in the initial state and two hadrons in the final state, denoted as 1 + J → 2 + J . This class of amplitude is relevant in precision tests of the Standard Model as well as for exploring the structure of excited states in the QCD spectrum. We present a model-independent description of the amplitudes where we sum to all orders in the strong interaction. From this analytic form we are able to extract transition and elastic resonance form factors consistent with previous work …

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Observation Of Azimuth-Dependent Suppression Of Hadron Pairs In Electron Scattering Off Nuclei, S. J. Paul, S. Morán, M. Arratia, A. El Alaoui, H. Hakobyan, W. Brooks, M. J. Amaryan, W. R. Armstrong, H. Atac, L. Baashen, N. A. Baltzell, L. Barion, M. Bashkanov, M. Battaglieri, I. Bedlinskiy, B. Benkel, F. Benmokhtar, A. Bianconi, L. Biondo, A. S. Biselli, M. Bondi, F. Bossù, S. Boiarinov, K.-Th. Brinkmann, W. J. Briscoe, D. Bulumulla, V. D. Burkert, R. Capobianco, D. S. Carman, A. Celentano, V. Chesnokov, T. Chetry, G. Ciullo, P. L. Cole, M. Contalbrigo, G. Constantini, A. D' Angelo, N. Dashyan, R. De Vita, M. Defurne, A. Deur, S. Diehl, C. Dilks, C. Djalali, R. Dupre, H. Egiyan, L. El Fassi, P. Eugenio, S. Fegan, A. Filippi, G. Gavalian, Y. Ghandilyan, G. P. Gilfoyle, A. A. Golubenko, G. Gosta, R. W. Gothe, K. A. Griffioen, M. Guidal, M. Hattawy, T. B. Hayward, D. Heddle, A. Hobart, M. Holtrop, Y. Ilieva, D. G. Ireland, E. L. Isupov, H. S. Jo, R. Johnston, K. Joo, S. Joosten, D. Keller, A. Khanal, M. Khandaker, W. Kim, A. Kripko, V. Kubarovsky, V. Lagerquist, L. Lanza, M. Leali, S. Lee, P. Lenisa, X. Li, K. Livingston, I.J.D. Macgregor, D. Marchand, V. Mascagna, B. Mckinnon, Z. E. Meziani, S. Migliorati, R. G. Milner, T. Mineeva, M. Mirazita, V. I. Mokeev, P. Moran, C. Munoz Camacho, K. Neupane, D. Nguyen, S. Niccolai, G. Niculescu, M. Osipenko, A. I. Ostrovidov, P. Pandey, M. Paolone, L. L. Pappalardo, R. Paremuzyan, E. Pasyuk, W. Phelps, N. Pilleux, D. Pocanic, O. Pogorelko, M. Pokhrel, J. Poudel, J. W. Price, Y. Prok, B. A. Raue, T. Reed, M. Ripani, G. Rosner, F. Sabatié, C. Salgado, A. Schmidt, R. A. Schumacher, Y. G. Sharabian, E. V. Shirokov, U. Shrestha, P. Simmerling, D. Sokhan, N. Sparveris, S. Stepanyan, I. I. Strakovsky, S. Strauch, J. A. Tan, R. Tyson, M. Ungaro, S. Vallarino, L. Venturelli, H. Voskanyan, E. Voutier, X. Wei, R. Wishart, M. H. Wood, N. Zachariou, Z. W. Zhao, V. Ziegler, M. Zurek Jan 2022

Observation Of Azimuth-Dependent Suppression Of Hadron Pairs In Electron Scattering Off Nuclei, S. J. Paul, S. Morán, M. Arratia, A. El Alaoui, H. Hakobyan, W. Brooks, M. J. Amaryan, W. R. Armstrong, H. Atac, L. Baashen, N. A. Baltzell, L. Barion, M. Bashkanov, M. Battaglieri, I. Bedlinskiy, B. Benkel, F. Benmokhtar, A. Bianconi, L. Biondo, A. S. Biselli, M. Bondi, F. Bossù, S. Boiarinov, K.-Th. Brinkmann, W. J. Briscoe, D. Bulumulla, V. D. Burkert, R. Capobianco, D. S. Carman, A. Celentano, V. Chesnokov, T. Chetry, G. Ciullo, P. L. Cole, M. Contalbrigo, G. Constantini, A. D' Angelo, N. Dashyan, R. De Vita, M. Defurne, A. Deur, S. Diehl, C. Dilks, C. Djalali, R. Dupre, H. Egiyan, L. El Fassi, P. Eugenio, S. Fegan, A. Filippi, G. Gavalian, Y. Ghandilyan, G. P. Gilfoyle, A. A. Golubenko, G. Gosta, R. W. Gothe, K. A. Griffioen, M. Guidal, M. Hattawy, T. B. Hayward, D. Heddle, A. Hobart, M. Holtrop, Y. Ilieva, D. G. Ireland, E. L. Isupov, H. S. Jo, R. Johnston, K. Joo, S. Joosten, D. Keller, A. Khanal, M. Khandaker, W. Kim, A. Kripko, V. Kubarovsky, V. Lagerquist, L. Lanza, M. Leali, S. Lee, P. Lenisa, X. Li, K. Livingston, I.J.D. Macgregor, D. Marchand, V. Mascagna, B. Mckinnon, Z. E. Meziani, S. Migliorati, R. G. Milner, T. Mineeva, M. Mirazita, V. I. Mokeev, P. Moran, C. Munoz Camacho, K. Neupane, D. Nguyen, S. Niccolai, G. Niculescu, M. Osipenko, A. I. Ostrovidov, P. Pandey, M. Paolone, L. L. Pappalardo, R. Paremuzyan, E. Pasyuk, W. Phelps, N. Pilleux, D. Pocanic, O. Pogorelko, M. Pokhrel, J. Poudel, J. W. Price, Y. Prok, B. A. Raue, T. Reed, M. Ripani, G. Rosner, F. Sabatié, C. Salgado, A. Schmidt, R. A. Schumacher, Y. G. Sharabian, E. V. Shirokov, U. Shrestha, P. Simmerling, D. Sokhan, N. Sparveris, S. Stepanyan, I. I. Strakovsky, S. Strauch, J. A. Tan, R. Tyson, M. Ungaro, S. Vallarino, L. Venturelli, H. Voskanyan, E. Voutier, X. Wei, R. Wishart, M. H. Wood, N. Zachariou, Z. W. Zhao, V. Ziegler, M. Zurek

Physics Faculty Publications

We present the first measurement of dihadron angular correlations in electron-nucleus scattering. The data were taken with the CLAS detector and a 5.0 GeV electron beam incident on deuterium, carbon, iron, and lead targets. Relative to deuterium, the nuclear yields of charged-pion pairs show a strong suppression for azimuthally opposite pairs, no suppression for azimuthally nearby pairs, and an enhancement of pairs with large invariant mass. These effects grow with increased nuclear size. The data are qualitatively described by the gibuu model, which suggests that hadrons form near the nuclear surface and undergo multiple scattering in nuclei. These results show …

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Solving Relativistic Three-Body Integral Equations In The Presence Of Bound States And Resonances, Taylor R. Powell, Raúl A. Briceño, Andrew W. Jackura Jan 2021

Solving Relativistic Three-Body Integral Equations In The Presence Of Bound States And Resonances, Taylor R. Powell, Raúl A. Briceño, Andrew W. Jackura

Physics: Accelerator and Nuclear Physics at the Thomas Jefferson National Accelerator Facility in Newport News, Virginia

Three-body interactions play an important role throughout modern-day particle, nuclear, and hadronic physics; many experimentally observed reactions of interest for testing the Standard Model result in final states composed of three particles or more. Due to these issues, a full description of three-body interactions from Quantum Chromodynamics is required. The focus of this project was to extend previous results for a two-body subsystem with a bound state to include resonance channels. We first derived a novel single-variable observable, denoted as an intensity distribution, which is proportional to the probability density of the three-body scattering amplitude. We explored this distribution in …

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A Hard X-Ray Compton Source At Cbeta, K.E. Deitrick, J. Crone, C. Franck, G.H. Hoffstaetter, Geoffrey A. Krafft, B. D. Muratori, H. L. Owen, Balša Terzić, P. H. Williams Jan 2021

A Hard X-Ray Compton Source At Cbeta, K.E. Deitrick, J. Crone, C. Franck, G.H. Hoffstaetter, Geoffrey A. Krafft, B. D. Muratori, H. L. Owen, Balša Terzić, P. H. Williams

Physics Faculty Publications

Inverse Compton scattering (ICS) holds the potential for future high flux, narrow bandwidth x-ray sources driven by high quality, high repetition rate electron beams. CBETA, the Cornell-BNL Energy recovery linac (ERL) Test Accelerator, is the world’s first superconducting radiofrequency multi-turn ERL, with a maximum energy of 150 MeV, capable of ICS production of x-rays above 400 keV. We present an update on the bypass design and anticipated parameters of a compact ICS source at CBETA. X-ray parameters from the CBETA ICS are compared to those of leading synchrotron radiation facilities, demonstrating that, above a few hundred keV, photon beams produced …

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Consistency Checks For Two-Body Finite-Volume Matrix Elements. Ii. Perturbative Systems, Raúl A. Briceño, Maxwell T. Hansen, Andrew W. Jackura May 2020

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 the …

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Heavy Quark Expansion For Heavy-Light Light-Cone Operators, Shuai Zhao Apr 2020

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 …

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Quasielastic Lepton Scattering And Back-To-Back Nucleons In The Short-Time Approximation, S. Pastore, J. Carlson, S. Gandolfi, R. Schiavilla, R. B. Wiringa Jan 2020

Quasielastic Lepton Scattering And Back-To-Back Nucleons In The Short-Time Approximation, S. Pastore, J. Carlson, S. Gandolfi, R. Schiavilla, R. B. Wiringa

Physics Faculty Publications

Understanding quasielastic electron and neutrino scattering from nuclei has taken on new urgency with current and planned neutrino oscillation experiments, and with electron scattering experiments measuring specific final states, such as those involving nucleon pairs in "back-to-back" configurations. Accurate many-body methods are available for calculating the response of light (A <= 12) nuclei to electromagnetic and weak probes, but they are computationally intensive and only applicable to the inclusive response. In the present work we introduce a novel approach, based on realistic models of nuclear interactions and currents, to evaluate the short-time (high-energy) inclusive and exclusive response of nuclei. The approach accounts reliably for crucial two-nucleon dynamics, including correlations and currents, and provides information on back-to-back nucleons observed in electron and neutrino scattering experiments. We demonstrate that in the quasielastic regime and at moderate momentum transfers both initial- and final-state correlations and two-nucleon currents are important for a quantitatively successful description of the inclusive response and final-state nucleons. Finally, the approach can be extended to include relativistic-kinematical and dynamical-effects, at least approximately in the two-nucleon sector, and to describe the response in the resonance-excitation region.

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Klf Analysis Report: Meson Spectroscopy Simulation Studies, Shankar Adhikari, Moskov Amaryan Jan 2020

Klf Analysis Report: Meson Spectroscopy Simulation Studies, Shankar Adhikari, Moskov Amaryan

Physics Faculty Publications

This analysis report is written as a supplemental for the strange meson spectroscopy part of the KLF proposal submitted to the JLab PAC48.

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Long-Range Electroweak Amplitudes Of Single Hadrons From Euclidean Finite-Volume Correlation Functions, Raúl A. Briceño, Zohreh Davoudi, Maxwell T. Hansen, Matthias R. Schindler, Alessandro Baroni Jan 2020

Long-Range Electroweak Amplitudes Of Single Hadrons From Euclidean Finite-Volume Correlation Functions, Raúl A. Briceño, Zohreh Davoudi, Maxwell T. Hansen, Matthias R. Schindler, Alessandro Baroni

Physics Faculty Publications

A relation is presented between single-hadron long-range matrix elements defined in a finite Euclidean spacetime and the corresponding infinite-volume Minkowski amplitudes. This relation is valid in the kinematic region where any number of two-hadron states can simultaneously go on shell, so that the effects of strongly coupled intermediate channels are included. These channels can consist of nonidentical particles with arbitrary intrinsic spins. The result accommodates general Lorentz structures as well as nonzero momentum transfer for the two external currents inserted between the single-hadron states. The formalism, therefore, generalizes the work by Christ et al. [Phys. Rev. D 91, 114510 …

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Consistency Checks For Two-Body Finite-Volume Matrix Elements: Conserved Currents And Bound States, Raúl A. Briceño, Maxwell T. Hansen, Andrew W. Jackura Dec 2019

Consistency Checks For Two-Body Finite-Volume Matrix Elements: Conserved Currents And Bound States, Raúl A. Briceño, Maxwell T. Hansen, Andrew W. Jackura

Physics Faculty Publications

Recently, a framework has been developed to study form factors of two-hadron states probed by an external current. The method is based on relating finite-volume matrix elements, computed using numerical lattice QCD, to the corresponding infinite-volume observables. As the formalism is complicated, it is important to provide nontrivial checks on the final results and also to explore limiting cases in which more straightforward predictions may be extracted. In this work we provide examples on both fronts. First, we show that, in the case of a conserved vector current, the formalism ensures that the finite-volume matrix element of the conserved charge …

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Comparing Proton Momentum Distributions In A = 2 And 3 Nuclei Via 2H 3H And 3He (E,E′P) Measurements, R. Cruz-Torres, F. Hauenstein, A. Schmidt, D. Nguyen, D. Abrams, H. Albataineh, S. Alsalmi, D. Androic, K. Aniol, W. Armstrong, J. Arrington, H. Atac, D. Bulumulla, C. E. Hyde, V. Khachatryan, M. N.H. Rashad, L. B. Weinstein, Z. Y. Ye, J. Zhang, Jefferson Lab Hall A Tritium Collaboration Oct 2019

Comparing Proton Momentum Distributions In A = 2 And 3 Nuclei Via 2H 3H And 3He (E,E′P) Measurements, R. Cruz-Torres, F. Hauenstein, A. Schmidt, D. Nguyen, D. Abrams, H. Albataineh, S. Alsalmi, D. Androic, K. Aniol, W. Armstrong, J. Arrington, H. Atac, D. Bulumulla, C. E. Hyde, V. Khachatryan, M. N.H. Rashad, L. B. Weinstein, Z. Y. Ye, J. Zhang, Jefferson Lab Hall A Tritium Collaboration

Physics Faculty Publications

We report the first measurement of the (e, e' p) reaction cross-section ratios for Helium-3 (3He), Tritium (3H), and Deuterium (d). The measurement covered a missing momentum range of 40 ≤ pmiss ≤ 550 MeV/c, at large momentum transfer ({Q2} ≈ 1.9 (GeV/c)2) and xB > 1, which minimized contributions from non quasi-elastic (QE) reaction mechanisms. The data is compared with planewave impulse approximation (PWIA) calculations using realistic spectral functions and momentum distributions. The measured and PWIA-calculated cross-section ratios for 3He/d and 3H/d extend to just above the typical …

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Nuclear Theory And Event Generators For Charge-Changing Neutrino Reactions, J. W. Van Orden, T. W. Donnelly Oct 2019

Nuclear Theory And Event Generators For Charge-Changing Neutrino Reactions, J. W. Van Orden, T. W. Donnelly

Physics Faculty Publications

Semi-inclusive CCν cross sections based on factorized cross sections are studied for a selection of spectral function models with the objective of facilitating the choice of models for use as input into event generators. The basic formalism for such cross sections is presented along with an introduction to constructing spectral functions for simple models based on the independent-particle shell model, the relativistic Fermi gas model (RFG), and a local density approximation (LDA) based on the RFG. Spectral functions for these models are shown for 16O along with a more sophisticated model which includes nucleon-nucleon interactions [AlvarezRuso et al., Prog. …

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Muon Capture In Nuclei: An Ab Initio Approach Based On Green's Function Monte Carlo Methods, A. Lovato, N. Rocco, Rocco Schiavilla Sep 2019

Muon Capture In Nuclei: An Ab Initio Approach Based On Green's Function Monte Carlo Methods, A. Lovato, N. Rocco, Rocco Schiavilla

Physics Faculty Publications

An ab initio Green’s function Monte Carlo (GFMC) method is introduced for calculating total rates of muon weak capture in light nuclei with mass number A ≤ 12. As a first application of the method, we perform a calculation of the rate in 3H and 4He in a dynamical framework based on realistic two- and three-nucleon interactions and realistic nuclear charge-changing weak currents. The currents include one- and two-body terms induced by π-and ρ-meson exchange, and N-to-Δ excitation, and are constrained to reproduce the empirical value of the Gamow-Teller matrix element in tritium. We investigate the sensitivity of …

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Unitarity Of The Infinite-Volume Three-Particle Scattering Amplitude Arising From A Finite-Volume Formalism, Raúl A. Briceño, Maxwell T. Hansen, Stephen R. Sharpe, Adam P. Szczepaniak Sep 2019

Unitarity Of The Infinite-Volume Three-Particle Scattering Amplitude Arising From A Finite-Volume Formalism, Raúl A. Briceño, Maxwell T. Hansen, Stephen R. Sharpe, Adam P. Szczepaniak

Physics Faculty Publications

Hansen and Sharpe [Phys. Rev. D 92, 114509 (2015)] derived a relation between the scattering amplitude of three identical bosons,M3, and a real function referred to as the divergence-free K matrix and denoted Kdf;3. The result arose in the context of a relation between finite-volume energies and Kdf;3, derived to all orders in the perturbative expansion of a generic low-energy effective field theory. In this work we set aside the role of the finite volume and focus on the infinite-volume relation between Kdf;3 and M3. We show that, for any …

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Structure Of Parton Quasi-Distributions And Their Moments, A. V. Radyushkin Jan 2019

Structure Of Parton Quasi-Distributions And Their Moments, A. V. Radyushkin

Physics Faculty Publications

We discuss the structure of the parton quasi-distributions (quasi-PDFs) Q (y, P-3) outside the "canonical" -1 <= y <= 1 support region of the usual parton distribution functions (PDFs). Writing the y(n) moments of Q (y, P-3) in terms of the combined x(n-2l)k(perpendicular to)(2l)-moments of the transverse momentum distribution (TMD). F(x,k(perpendicular to)(2)), we establish a connection between the large-vertical bar y vertical bar behavior of Q (y, P-3) and large-k(perpendicular to)(2) behavior of F(x,k(perpendicular to)(2)). In particular, we show that the 1/k(perpendicular to)(2) hard tail of TMDs in QCD results in a slowly decreasing similar to 1/vertical bar y vertical bar behavior of quasi-PDFs for large vertical bar y vertical bar that produces infinite y(n) moments of Q(y, P-3). We also relate the - 1/vertical bar y vertical bar terms with the lnz(3)(2)-singularities of the Ioffe-time pseudo-distributions m(v, z(3)(2)). Converting the operator product expansion for m(v,z(3)(2)) into a matching relation between the quasi-PDF Q(y, P-3) and the light-cone PDF f (x, mu(2)), we demonstrate that there is no contradiction between the infinite values of the y(n) moments of Q (y, P-3) and finite values of the x(n) moments of f (x, mu(2))

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Form Factors Of Two-Hadron States From A Covariant Finite-Volume Formalism, Alessandro Baroni, Raúl Briceño, Maxwell T. Hansen, Felipe G. Ortega-Gama Jan 2019

Form Factors Of Two-Hadron States From A Covariant Finite-Volume Formalism, Alessandro Baroni, Raúl Briceño, Maxwell T. Hansen, Felipe G. Ortega-Gama

Physics Faculty Publications

In this work we develop a Lorentz-covariant version of the previously derived formalism for relating finite-volume matrix elements to 2 + J → 2 transition amplitudes. We also give various details relevant for the implementation of this formalism in a realistic numerical lattice QCD calculation. Particular focus is given to the role of single-particle form factors in disentangling finite-volume effects from the triangle diagram that arise when J couples to one of the two hadrons. This also leads to a new finite-volume function, denoted G, the numerical evaluation of which is described in detail. As an example we discuss …

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Challenges With Large Transverse Momentum In Semi-Inclusive Deeply Inelastic Scattering, J. O. Gonzalez-Hernandez, T. C. Rogers, N. Sato, B. Wang Dec 2018

Challenges With Large Transverse Momentum In Semi-Inclusive Deeply Inelastic Scattering, J. O. Gonzalez-Hernandez, T. C. Rogers, N. Sato, B. Wang

Physics Faculty Publications

We survey the current phenomenological status of semi-inclusive deeply inelastic scattering at moderate hard scales and in the limit of very large transverse momentum. As the transverse momentum becomes comparable to or larger than the overall hard scale, the differential cross sections should be calculable with fixed order perturbative QCD (pQCD) methods, while small transverse momentum (transverse-momentum-dependent factorization) approximations should eventually break down. We find large disagreement between HERMES and COMPASS data and fixed order calculations done with modern parton densities, even in regions of kinematics where such calculations should be expected to be very accurate. Possible interpretations are suggested.

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High-Brilliance, High-Flux Compact Inverse Compton Light Source, K. E. Deitrick, G. A. Krafft, B. Terzić, J. R. Delayen Aug 2018

High-Brilliance, High-Flux Compact Inverse Compton Light Source, K. E. Deitrick, G. A. Krafft, B. Terzić, J. R. Delayen

Physics Faculty Publications

The Old Dominion University Compact Light Source (ODU CLS) design concept is presented-a compact Inverse Compton Light Source (ICLS) with flux and brilliance orders of magnitude beyond conventional laboratory-scale sources and greater than other compact ICLS designs. This concept utilizes the physics of inverse Compton scattering of an extremely low emittance electron beam by a laser pulse of rms length of approximately two-thirds of a picosecond (2/3 ps). The accelerator is composed of a superconducting radio frequency (SRF) reentrant gun followed by four double-spoke SRF cavities. After the linac are three quadrupole magnets to focus the electron beam to the …

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Probing High-Momentum Protons And Neutrons In Neutron-Rich Nuclei, The Clas Collaboration, L. B. Weinstein, S. Bültmann, D. Bulumulla, G. Charles, G. Dodge, F. Hauenstein, C. E. Hyde, A. Klein, S. Nadeeshani, Y. Prok, Z. W. Zhao Aug 2018

Probing High-Momentum Protons And Neutrons In Neutron-Rich Nuclei, The Clas Collaboration, L. B. Weinstein, S. Bültmann, D. Bulumulla, G. Charles, G. Dodge, F. Hauenstein, C. E. Hyde, A. Klein, S. Nadeeshani, Y. Prok, Z. W. Zhao

Physics Faculty Publications

The atomic nucleus is one of the densest and most complex quantum-mechanical systems in nature. Nuclei account for nearly all the mass of the visible Universe. The properties of individual nucleons (protons and neutrons) in nuclei can be probed by scattering a high-energy particle from the nucleus and detecting this particle after it scatters, often also detecting an additional knocked-out proton. Analysis of electron- and proton-scattering experiments suggests that some nucleons in nuclei form close-proximity neutron–proton pairs with high nucleon momentum, greater than the nuclear Fermi momentum. However, how excess neutrons in neutron-rich nuclei form such close-proximity pairs remains unclear. …

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One-Loop Evolution Of Parton Pseudo-Distribution Functions On The Lattice, Anatoly Radyushkin Jul 2018

One-Loop Evolution Of Parton Pseudo-Distribution Functions On The Lattice, Anatoly Radyushkin

Physics Faculty Publications

We incorporate recent calculations of one-loop corrections for the reduced Ioffe-time pseudo-distribution m(v, z(3)(2) thorn to extend the leading-logarithm analysis of lattice data obtained by Orginos et al. We observe that the one-loop corrections contain a large term reflecting the fact that effective distances involved in the most important diagrams are much smaller than the nominal distance z(3). The large correction in this case may be absorbed into the evolution term, and the perturbative expansion used for extraction of parton densities at the μ ≈ 2 GeV scale is under control. The extracted parton distribution is rather close to global …

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Electron- And Positron-Impact Ionization Of Inert Gases, R. I. Campeanu, H. R. J. Walters, Colm T. Whelan Jun 2018

Electron- And Positron-Impact Ionization Of Inert Gases, R. I. Campeanu, H. R. J. Walters, Colm T. Whelan

Physics Faculty Publications

Triple-differential cross sections (TDCS) are presented for the electron and positron impact ionization of inert gas atoms in a range of geometries where a number of significant few body effects compete to define the shape of the TDCS. Using both positrons and electrons as projectiles has opened up the possibility of performing complementary studies which could effectively isolate competing interactions which cannot be separately detected in an experiment with a single projectile. A comparison is presented between theory and the recent experiments of [Gavin, deLucio, and DuBois, Phys. Rev. A95, 062703 (2017)] for e± and contrasted with the …

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Nucleon And Nuclear Structure Through Dilepton Production, I. V. Anikin, N. Baltzell, M. Boer, R. Boussarie, V. M. Braun, S. J. Brodsky, A. Camsonne, W. C. Chang, L. Colaneri, C. E. Hyde Apr 2018

Nucleon And Nuclear Structure Through Dilepton Production, I. V. Anikin, N. Baltzell, M. Boer, R. Boussarie, V. M. Braun, S. J. Brodsky, A. Camsonne, W. C. Chang, L. Colaneri, C. E. Hyde

Physics Faculty Publications

Transverse momentum distributions and generalized parton distributions provide a comprehensive framework for the three-dimensional imaging of the nucleon and the nucleus experimentally using deeply virtual semi-exclusive and exclusive processes. The advent of combined high luminosity facilities and large acceptance detector capabilities enables experimental investigation of the partonic structure of hadrons with time-like virtual probes, in complement to the rich on-going space-like virtual probe program. The merits and benefits of the dilepton production channel for nuclear structure studies are discussed within the context of the International Workshop on Nucleon and Nuclear Structure through Dilepton Production taking place at the European Center …

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Simulation Of Inverse Compton Scattering And Its Implications On The Scattered Linewidth, N. Ranjan, B. Terzić, G. A. Krafft, V. Petrillo, I. Drebot, L. Serafini Jan 2018

Simulation Of Inverse Compton Scattering And Its Implications On The Scattered Linewidth, N. Ranjan, B. Terzić, G. A. Krafft, V. Petrillo, I. Drebot, L. Serafini

Physics Faculty Publications

Rising interest in inverse Compton sources has increased the need for efficient models that properly quantify the behavior of scattered radiation given a set of interaction parameters. The current state-of-the-art simulations rely on Monte Carlo-based methods, which, while properly expressing scattering behavior in high-probability regions of the produced spectra, may not correctly simulate such behavior in low-probability regions (e.g. tails of spectra). Moreover, sampling may take an inordinate amount of time for the desired accuracy to be achieved. In this paper, we present an analytic derivation of the expression describing the scattered radiation linewidth and propose a model to describe …

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Search For Three-Nucleon Short-Range Correlations In Light Nuclei, Z. Ye, P. Solvignon, D. Nguten, P. Aguilera, Z. Ahmed, H. Albataineh, K. Allada, B. Anderson, D. Anez, L. B. Weinstein Jan 2018

Search For Three-Nucleon Short-Range Correlations In Light Nuclei, Z. Ye, P. Solvignon, D. Nguten, P. Aguilera, Z. Ahmed, H. Albataineh, K. Allada, B. Anderson, D. Anez, L. B. Weinstein

Physics Faculty Publications

We present new data probing short-range correlations (SRCs) in nuclei through the measurement of electron scattering off high-momentum nucleons in nuclei. The inclusive 4He/3He cross section ratio is observed to be both x and Q2 independent for 1.5 < x < 2, confirming the dominance of two-nucleon short-range correlations. For x > 2, our data support the hypothesis that a previous claim of three-nucleon correlation dominance was an artifact caused by the limited resolution of the measurement. While 3N-SRCs appear to have an important contribution, our data show that isolating 3N-SRCs is significantly more complicated than for 2N-SRCs.

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Numerical Study Of The Relativistic Three-Body Quantization Condition In The Isotropic Approximation, Raúl A. Briceño, Maxwell T. Hansen, Stephen R. Sharpe Jan 2018

Numerical Study Of The Relativistic Three-Body Quantization Condition In The Isotropic Approximation, Raúl A. Briceño, Maxwell T. Hansen, Stephen R. Sharpe

Physics Faculty Publications

We present numerical results showing how our recently proposed relativistic three-particle quantization condition can be used in practice. Using the isotropic (generalized s-wave) approximation, and keeping only the leading terms in the effective range expansion, we show how the quantization condition can be solved numerically in a straightforward manner. In addition, we show how the integral equations that relate the intermediate three-particle infinite-volume scattering quantity, Kdf,3, to the physical scattering amplitude can be solved at and below threshold. We test our methods by reproducing known analytic results for the 1/L expansion of the threshold state, the volume …

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

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(3), z(3)(2))/M(Pz(3), z(3)(2)) has a Gaussian-type behavior with respect to z(3) for 6 values of P used in …

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Angular Distribution Of Single-Photon Superradiance In A Dilute And Cold Atomic Ensemble, A. S. Kuraptsev, I. M. Sokolov, M. D. Havey Aug 2017

Angular Distribution Of Single-Photon Superradiance In A Dilute And Cold Atomic Ensemble, A. S. Kuraptsev, I. M. Sokolov, M. D. Havey

Physics Faculty Publications

On the basis of a quantum microscopic approach we study the dynamics of the afterglow of a dilute Gaussian atomic ensemble excited by pulsed radiation. Taking into account the vector nature of the electromagnetic field we analyze in detail the angular and polarization distribution of single-photon superradiance of such an ensemble. The dependence of the angular distribution of superradiance on the length of the pulse and its carrier frequency as well as on the size and the shape of the atomic clouds is studied. We show that there is substantial dependence of the superradiant emission on the polarization and the …

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Rosenbluth Separation Of The Π0 Electroproduction Cross Section Off The Neutron, M. Mazouz, Z. Ahmed, H. Albataineh, K. Allada, K. A. Aniol, V. Bellini, M. Benali, W. Boeglin, P. Bertin, M. Canan, C. E. Hyde, S. Koirala, M. N. H. Rashad Jun 2017

Rosenbluth Separation Of The Π0 Electroproduction Cross Section Off The Neutron, M. Mazouz, Z. Ahmed, H. Albataineh, K. Allada, K. A. Aniol, V. Bellini, M. Benali, W. Boeglin, P. Bertin, M. Canan, C. E. Hyde, S. Koirala, M. N. H. Rashad

Physics Faculty Publications

We report the first longitudinal-transverse separation of the deeply virtual exclusive π0 electroproduction cross section off the neutron and coherent deuteron. The corresponding four structure functions dσL/dt, dσT/dt, dσLT/dt, and dσTT/dt are extracted as a function of the momentum transfer to the recoil system at Q2 = 1.75 GeV2 and xB = 0.36. The ed -> edπ0 cross sections are found compatible with the small values expected from theoretical models. The en -> enπ0 cross sections show a dominance from the response to transversely polarized …

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Exclusive Η Electroproduction At W > 2 Gev With Clas And Transversity Generalized Parton Distributions, I. Bedlinskiy, V. Kubarovsky, P. Stoler, K. P. Adhikari, Z. Akbar, S. Anefalos Pereira, H. Avakian, J. Ball, N. A. Baltzell, M. Battaglieri, C. E. Hyde, M. Khachatryan, S E. Kuhn, Y. Prok, B. Torayev, L. B. Weinstein Mar 2017

Exclusive Η Electroproduction At W > 2 Gev With Clas And Transversity Generalized Parton Distributions, I. Bedlinskiy, V. Kubarovsky, P. Stoler, K. P. Adhikari, Z. Akbar, S. Anefalos Pereira, H. Avakian, J. Ball, N. A. Baltzell, M. Battaglieri, C. E. Hyde, M. Khachatryan, S E. Kuhn, Y. Prok, B. Torayev, L. B. Weinstein

Physics Faculty Publications

The cross section of the exclusive η electroproduction reaction ep -> e'p' η was measured at Jefferson Laboratory with a 5.75 GeV electron beam and the CLAS detector. Differential cross sections d4σ /dtdQ2 dxBd φη and structure functions σU=σT + εσL, σTT, and σLT, as functions of t, were obtained over a wide range of Q2 and xB. The η structure functions are compared with those previously measured for π0 at the same kinematics. At low t, both π …

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Nonperturbative Evolution Of Parton Quasi-Distributions, A. V. Radyushkin Jan 2017

Nonperturbative Evolution Of Parton Quasi-Distributions, A. V. Radyushkin

Physics Faculty Publications

Using the formalism of parton virtuality distribution functions (VDFs) we establish a connection between the transverse momentum dependent distributions (TMDs) F(x,k2⊥) and quasi-distributions (PQDs) Q(y,p3) introduced recently by X. Ji for lattice QCD extraction of parton distributions f(x). We build models for PQDs from the VDF-based models for soft TMDs, and analyze the p3 dependence of the resulting PQDs. We observe a strong nonperturbative evolution of PQDs for small and moderately large values of p3 reflecting the transverse momentum dependence of TMDs. Thus, the study of PQDs on the lattice …

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