Measurement of the Parity-Violating Asymmetry in Deep Inelastic Scattering at JLab 6 GeV
- Univ. of Virginia, Charlottesville, VA (United States)
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 Q2 values of 1.1 and 1.9 (GeV/c)2. The asymmetry at Q2=1.9 (GeV/c)2 can be used to extract the weak coupling combination 2C2u - C2d, 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 Q2 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 APV data in the resonance region beyond the Δ (1232). They provide evidence that the quark hadron duality works for APV 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.
- Research Organization:
- Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
- Sponsoring Organization:
- USDOE Office of Science, Nuclear Physics
- DOE Contract Number:
- AC05-06OR23177
- OSTI ID:
- 1133072
- Report Number(s):
- JLAB-PHY-13-1849; DOE/OR/23177-3083; TRN: US1400438
- Country of Publication:
- United States
- Language:
- English
Similar Records
Searches for Physics beyond the Standard Model
Parity violation in deep inelastic scattering at JLab 6 GeV.