The Spin Asymmetries of the Nucleon Experiment (SANE) measured two double spin asymmetries using a polarized proton target and polarized electron beam at two beam energies, 4.7 GeV and 5.9 GeV. A large-acceptance open-configuration detector package identified scattered electrons at 40 • and covered a wide range in Bjorken x (0.3 < x < 0.8). Proportional to an average color Lorentz force, the twist-3 matrix element,d p 2 , was extracted from the measured asymmetries at Q 2 values ranging from 2.0 to 6.0 GeV 2 . The data display the opposite sign compared to most quark models, including the lattice QCD result, and an apparently unexpected scale dependence. Furthermore when combined with the neutron data in the same Q 2 range the results suggest a flavor independent average color Lorentz force.Today, it is accepted that Quantum Chromodynamics (QCD), the gauge theory of strong interactions, plays a central role in our understanding of nucleon structure at the heart of most visible matter in the universe. QCD successfully describes many observables in high energy scattering processes where the coupling among the con-fined constituents of hadrons (quarks and gluons) is weak and perturbative (pQCD) calculations are possible, taking advantage of factorization theorems and evolution equations similar to quantum electrodynamics (QED). At the same time, QCD offers a clear path to unravel the non-perturbative structure of hadrons using lattice QCD, arXiv:1805.08835v4 [nucl-ex]
SUMMARY -Leptomeningeal metastasis (LM) is a rare but increasingly common condition in which malignant cells migrate to the meninges. The gold standard for diagnosing LM is detection of cancer cells in the cerebrospinal fluid (CSF). Contrast enhanced-magnetic resonance imaging (CE-MRI) is also used to diagnose LM. We describe a case of LM in which CE-MRI of the neuroaxis was initially negative for meningeal enhancement but F-18 fluorodeoxyglucose positron-emission tomography/computed tomography (F-18 FDG PET/CT) revealed hypermetabolism within the lumbar spinal canal. Positive F-18 FDG PET findings have rarely been reported in LM and, to our knowledge, have never been reported in the context of initially negative CE-MRI scanning of the neuroaxis. F-18 FDG PET/CT may represent an alternative modality for diagnosing LM in patients who are unable to undergo CE-MRI and/or LP or in patients for whom initial CE-MRI and/or LP are negative for LM.
The Spin Asymmetries of the Nucleon Experiment (SANE) performed inclusive, double-polarized electron scattering measurements of the proton at the Continuous Electron Beam Accelerator Facility at Jefferson Lab. A novel detector array observed scattered electrons of four-momentum transfer 2.5 < Q 2 < 6.5 GeV 2 and Bjorken scaling 0.3 < x < 0.8 from initial beam energies of 4.7 and 5.9 GeV. Employing a polarized proton target whose magnetic field direction could be rotated with respect to the incident electron beam, both parallel and near perpendicular spin asymmetries were measured, allowing model-independent access to transverse polarization observables A 1 , A 2 , g 1 , g 2 and moment d 2 of the proton. This document summarizes the operation and performance of the polarized target, polarized electron beam, and novel detector systems used during the course of the experiment, and describes analysis techniques utilized to access the physics observables of interest.
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