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Full-Text Articles in Physical Sciences and Mathematics

Tmd Phenomenology With The Hso Approach, Tommaso Rainaldi, M. Boglione, J. O. Gonzalez-Hernandez, Ted C. Rogers Jan 2024

Tmd Phenomenology With The Hso Approach, Tommaso Rainaldi, M. Boglione, J. O. Gonzalez-Hernandez, Ted C. Rogers

Physics Faculty Publications

Transverse momentum dependent (TMD) observables are typically classified in terms of their contributions coming from different regions in transverse momentum. The low transverse momentum behavior is often ascribed to intrinsic nonperturbative properties of the hadron described by TMD factorization, while the large transverse momentum region can be computed using fixed order collinear perturbation theory. Combining both pictures in a consistent way presents challenges, for practical calculations as well as the interpretation of results. We discuss a recent approach that is designed to retain a physical interpretation in terms of hadron structure while alleviating tension with techniques used at much higher …


Gluon Transverse-Momentum-Dependent Distributions From Large-Momentum Effective Theory, Ruilin Zhu, Yao Ji, Jian-Hui Zhang, Shuai Zhao Jan 2023

Gluon Transverse-Momentum-Dependent Distributions From Large-Momentum Effective Theory, Ruilin Zhu, Yao Ji, Jian-Hui Zhang, Shuai Zhao

Physics Faculty Publications

We demonstrate that gluon transverse-momentum-dependent parton distribution functions (TMDPDFs) can be extracted from lattice calculations of appropriate Euclidean correlations in large-momentum effective theory (LaMET). Based on perturbative calculations of gluon unpolarized and helicity TMDPDFs, we present a matching formula connecting them and their LaMET counterparts, where the latter are renormalized in a scheme facilitating lattice calculations and converted to the MS ¯ scheme. The hard matching kernel is given up to one-loop level. We also show that the perturbative result is independent of the prescription used for the pinch-pole singularity in the relevant correlations. Our results offer a guidance for …


Determination Of The Titanium Spectral Function From (E, E'P) Data, L. Jiang, A.M. Ankowski, D. Abrams, L. Gu, B. Aljawrneh, S. Alsalmi, J. Bane, A. Batz, S. Barcus, M. Barroso, V. Bellini, O. Benhar, J. Bericic, D. Biswas, A. Camsonne, J. Castellanos, J. -P. Chen, M. E. Christy, K. Craycraft, R. Cruz-Torres, H. Dai, D. Day, A. Dirican, S. -C. Dusa, E. Fuchey, T. Gautam, C. Giusti, J. Gomez, C. Gu, T. J. Hague, J. -O. Hansen, F. Hauenstein, D. W. Higinbotham, C. Hyde, Z. Jerzyk, A. M. Johnson, C. Keppel, C. Lanham, S. Li, R. Lindgren, H. Liu, C. Mariani, R. E. Mcclellan, D. Meekins, R. Michaels, M. Mihovilovic, M. Murphy, D. Nguyen, M. Nycz, L. Ou, B. Pandey, V. Pandey, K. Park, G. Perera, A.J.R. Puckett, S.N. Santiesteban, S. Ŝirca, T. Su, L. Tang, Y. Tian, N. Ton, B. Wojsekhowski, S. Wood, Z. Ye, J. Zhang Jan 2023

Determination Of The Titanium Spectral Function From (E, E'P) Data, L. Jiang, A.M. Ankowski, D. Abrams, L. Gu, B. Aljawrneh, S. Alsalmi, J. Bane, A. Batz, S. Barcus, M. Barroso, V. Bellini, O. Benhar, J. Bericic, D. Biswas, A. Camsonne, J. Castellanos, J. -P. Chen, M. E. Christy, K. Craycraft, R. Cruz-Torres, H. Dai, D. Day, A. Dirican, S. -C. Dusa, E. Fuchey, T. Gautam, C. Giusti, J. Gomez, C. Gu, T. J. Hague, J. -O. Hansen, F. Hauenstein, D. W. Higinbotham, C. Hyde, Z. Jerzyk, A. M. Johnson, C. Keppel, C. Lanham, S. Li, R. Lindgren, H. Liu, C. Mariani, R. E. Mcclellan, D. Meekins, R. Michaels, M. Mihovilovic, M. Murphy, D. Nguyen, M. Nycz, L. Ou, B. Pandey, V. Pandey, K. Park, G. Perera, A.J.R. Puckett, S.N. Santiesteban, S. Ŝirca, T. Su, L. Tang, Y. Tian, N. Ton, B. Wojsekhowski, S. Wood, Z. Ye, J. Zhang

Physics Faculty Publications

The E12-14-012 experiment, performed in Jefferson Lab Hall A, has measured the (e,e′p) cross section in parallel kinematics using a natural titanium target. In this paper, we report the analysis of the dataset obtained in different kinematics for our solid natural titanium target. Data were obtained in a range of missing momentum and missing energy between 15 ≲ pm ≲ 250  MeV/c and 12 ≲ Em ≲ 80  MeV, respectively, and using an electron beam energy of 2.2 GeV. We measured the reduced cross section with ∼7% accuracy as a function of both missing momentum and missing energy. …


Short-Range Correlations And The Nuclear Emc Effect In Deuterium And Helium-3, E. P. Segarra, J. R. Pybus, F. Hauenstien, D. W. Higinbotham, G. A. Miller, E. Piasetzky, A. Schmidt, M. Strikman, L. B. Weinstein, O. Hen Jan 2021

Short-Range Correlations And The Nuclear Emc Effect In Deuterium And Helium-3, E. P. Segarra, J. R. Pybus, F. Hauenstien, D. W. Higinbotham, G. A. Miller, E. Piasetzky, A. Schmidt, M. Strikman, L. B. Weinstein, O. Hen

Physics Faculty Publications

The EMC effect in deuterium and helium-3 is studied using a convolution formalism that allows isolating the impact of high-momentum nucleons in short-ranged correlated (SRC) pairs. We assume that the modification of the structure function of bound nucleons is given by a universal (i.e., nucleus independent) function of their virtuality, and find that the effect of such modifications is dominated by nucleons in SRC pairs. This SRC-dominance of nucleon modifications is observed despite the fact that the bulk of the nuclear inelastic scattering cross-section comes from interacting with low-momentum nucleons. These conclusions are found to be robust to model details …


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.


Question 1: Kale; Question 2: Hurricane Angular Momentum, Larry Weinstein Nov 2018

Question 1: Kale; Question 2: Hurricane Angular Momentum, Larry Weinstein

Physics Faculty Publications

A quiz concerning the amount of kale needed to provide calories for a person in a year and the angular momentum of Hurricane Florence when it made landfall.


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. Aug 2018

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. …


Exclusive Photoproduction Of Pi Degrees Up To Large Values Of Mandelstam Variables S, T, And U With Clas, M. C. Kunkel, M. J. Amaryan, I. I. Strakovsky, J. Ritman, G. R. Goldstein, K. P. Adhikari, S. Adhikari, Gerard P. Gilfoyle, Et. Al. Jul 2018

Exclusive Photoproduction Of Pi Degrees Up To Large Values Of Mandelstam Variables S, T, And U With Clas, M. C. Kunkel, M. J. Amaryan, I. I. Strakovsky, J. Ritman, G. R. Goldstein, K. P. Adhikari, S. Adhikari, Gerard P. Gilfoyle, Et. Al.

Physics Faculty Publications

Exclusive photoproduction cross sections have been measured for the process γp ->0 [e+ e- (γ)] with the Dalitz decay final state using tagged photon energies in the range of = 1.275 – 5.425 GeV. The complete angular distribution of the final state π0, for the entire photon energy range up to large values of t and u, has been measured for the first time. The data obtained show that the cross section dσ / dt, at mid to large angles, decreases with energy as s-6.89 +/- 0.26 …


Separated Response Functions In Exclusive, Forward Π± Electroproduction On Deuterium, G. M. Huber, H. P. Blok, A. Klein, L. M. Qin, K. Vansyoc, Jefferson Lab, Fπ Collaboration Jan 2015

Separated Response Functions In Exclusive, Forward Π± Electroproduction On Deuterium, G. M. Huber, H. P. Blok, A. Klein, L. M. Qin, K. Vansyoc, Jefferson Lab, Fπ Collaboration

Physics Faculty Publications

Background: Measurements of forward exclusive meson production at different squared four-momenta of the exchanged virtual photon, Q2, and at different four-momentum transfer, t, can be used to probe QCD's transition from meson-nucleon degrees of freedom at long distances to quark-gluon degrees of freedom at short scales. Ratios of separated response functions in π- and π+ electroproduction are particularly informative. The ratio for transverse photons may allow this transition to be more easily observed, while the ratio for longitudinal photons provides a crucial verification of the assumed pole dominance, needed for reliable extraction of the pion form …


Measurement Of The Differential Cross Section For The Reaction Γn →Π⁻P From Deuterium, M. J. Amaryan, H. Badasaryan, S. L. Careccia, G. E. Dodge, C. E. Hyde, S. E. Kuhn, F. Sabatié, S. Tkachenko, L. B. Weinstein, J. Zhang, Et Al., The Clas Collaboration Jan 2009

Measurement Of The Differential Cross Section For The Reaction Γn →Π⁻P From Deuterium, M. J. Amaryan, H. Badasaryan, S. L. Careccia, G. E. Dodge, C. E. Hyde, S. E. Kuhn, F. Sabatié, S. Tkachenko, L. B. Weinstein, J. Zhang, Et Al., The Clas Collaboration

Physics Faculty Publications

We report a measurement of the differential cross section for the γn →π⁻p process from the CLAS detector at Jefferson Laboratory in Hall B for photon energies between 1.0 and 3.5 GeV and pion center-of-mass (c.m.) angles (𝜃 c.m.) between 50° and 115°. We confirm a previous indication of a broad enhancement around a c.m. energy (√ s) of 2.1 GeV at 𝜃c.m. = 90° in the scaled differential cross section s7 dσdt and a rapid falloff in a center-of-mass energy region of about 400 MeV following the enhancement. Our data show an angular dependence of …


Two-Body Photodisintegration Of The Deuteron Up To 2.8 Gev, J. E. Belz, D. H. Potterveld, S. E. Kuhn, J.F. J. Van Den Brand, J. L. White, B. Zeidman, Et Al. Jan 1995

Two-Body Photodisintegration Of The Deuteron Up To 2.8 Gev, J. E. Belz, D. H. Potterveld, S. E. Kuhn, J.F. J. Van Den Brand, J. L. White, B. Zeidman, Et Al.

Physics Faculty Publications

Measurements were performed for the photodisintegration cross section of the deuteron for photon energies from 1.6 to 2.8 GeV and center-of-mass angles from 37° to 90°. The measured energy dependence of the cross section at θc.m. = 90° is in agreement with the constituent counting rules.