Preliminary results of a precision measurement of the neutron d2: Probing the Lorentz color force

Conference · Sun Apr 01 04:00:00 EDT 2012 · AIP Conf. Proc.

DOI:https://doi.org/10.1063/1.3700502· OSTI ID:1038758

The quantity d{sub 2}, related to a twist-three matrix element, is a measure of the average restoring Lorentz color force experienced by a quark inside a polarized nucleon after it is struck by a virtual photon in electron Deep Inelastic Scattering (DIS). With its information encoded in both spin structure functions g{sub 1} and g{sub 2} in the quark valence region at large Bjorken x, this confining local force is a result of the remnant di-quark system attracting the struck quark. While bag-and chiralsoliton-model calculations for the neutron d{sub 2} are consistent with those of lattice Quantum Chromodynamics (QCD), current experimental data differ by approximately two standard deviations from those theoretical results. To address this issue, the experiment E06-014 was carried out from February to March of 2009 at Jefferson Lab. It consisted of measuring doublespin asymmetries and the total cross section by scattering a longitudinally polarized electron beam from a longitudinally or transversely polarized {sup 3}He target, allowing for the extraction of the neutron d{sub 2}. The experiment covered excitation energies in the resonance and DIS valence quark regions. Preliminary cross sections and asymmetries will be presented.

• Research Organization: Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)
• Sponsoring Organization: USDOE Office of Science (SC)
• DOE Contract Number: AC05-06OR23177
• OSTI ID: 1038758
• Report Number(s): JLAB-PHY-11-1338; DOE/OR/23177-3710
• Conference Information: Journal Name: AIP Conf. Proc. Journal Volume: 1441
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
ACCURACY
COLOR
CROSS SECTIONS
DEEP INELASTIC SCATTERING
ELECTRON BEAMS
ELECTRONS
EXCITATION
MATRIX ELEMENTS
NEUTRONS
NUCLEONS
PHOTONS
QUANTUM CHROMODYNAMICS
QUARKS
RESONANCE
SCATTERING
SPIN
STRUCTURE FUNCTIONS
TOTAL CROSS SECTIONS
VALENCE