Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 10 of 10
Full-Text Articles in Physics
Challenges With Large Transverse Momentum In Semi-Inclusive Deeply Inelastic Scattering, J. O. Gonzalez-Hernandez, T. C. Rogers, N. Sato, B. Wang
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.
Probing High-Momentum Protons And Neutrons In Neutron-Rich Nuclei, M. Duer, C. L. A. S. Collaboration, O. Hen, E. Piasetzky, H. Hakobyan, L. B. Weistein, M. Braverman, Gerard P. Gilfoyle, Et. Al.
Probing High-Momentum Protons And Neutrons In Neutron-Rich Nuclei, M. Duer, C. L. A. S. Collaboration, O. Hen, E. Piasetzky, H. Hakobyan, L. B. Weistein, M. Braverman, Gerard P. Gilfoyle, Et. Al.
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. …
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
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. …
High-Brilliance, High-Flux Compact Inverse Compton Light Source, K. E. Deitrick, G. A. Krafft, B. Terzić, J. R. Delayen
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 …
One-Loop Evolution Of Parton Pseudo-Distribution Functions On The Lattice, Anatoly Radyushkin
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 …
Electron- And Positron-Impact Ionization Of Inert Gases, R. I. Campeanu, H. R. J. Walters, Colm T. Whelan
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 …
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
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 …
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
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.
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
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 …
Numerical Study Of The Relativistic Three-Body Quantization Condition In The Isotropic Approximation, Raúl A. Briceño, Maxwell T. Hansen, Stephen R. Sharpe
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 …