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Title: Measurement of the Parity-Violating Asymmetry in Deep Inelastic Scattering at JLab 6 GeV

The parity-violating asymmetry in deep inelastic scattering (PVDIS) offers us a useful tool to study the weak neutral couplings and the hadronic structure of the nucleon, and provides high precision tests on the Standard Model. During the 6 GeV PVDIS experiment at the Thomas Jefferson National Accelerator Facility, the parity-violating asymmetries A{sub PV} of a polarized electron beam scattering off an unpolarized deuteron target in the deep inelastic scattering region were precisely measured at two Q 2 values of 1.1 and 1.9 (GeV/c) 2. The asymmetry at Q 2=1.9 (GeV/c) 2 can be used to extract the weak coupling combination 2C 2u - C 2d, assuming the higher twist effect is small. The extracted result from this measurement is in good agreement with the Standard Model prediction, and improves the precision by a factor of five over previous data. In addition, combining the asymmetries at both Q 2 values provides us extra knowledge on the higher twist effects. The parity violation asymmetries in the resonance region were also measured during this experiment. These results are the first A PV data in the resonance region beyond the Δ (1232). They provide evidence that the quark hadron duality works for A PVmore » at the (10-15)% level, and set constraints on nucleon resonance models that are commonly used for background calculations to other parity-violating electron scattering measurements.« less
  1. Univ. of Virginia, Charlottesville, VA (United States)
Publication Date:
OSTI Identifier:
Report Number(s):
JLAB-PHY-13-1849; DOE/OR/23177-3083
TRN: US1400438
DOE Contract Number:
Resource Type:
Research Org:
Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)
Sponsoring Org:
USDOE Office of Science, Nuclear Physics
Country of Publication:
United States