Parity-violating electroweak asymmetry in {rvec e} p scattering
We have measured the parity-violating electroweak asymmetry in the elastic scattering of polarized electrons from protons. Significant contributions to this asymmetry could arise from the contributions of strange form factors in the nucleon. The measured asymmetry is A = -15.05 {+-} 0.98(stat) {+-} 0.56(syst) ppm at the kinematic point <{theta}{sub lab}> = 12.3{sup o} and <Q{sup 2}> = 0.477 (GeV/c){sup 2}. Based on these data as well as data on electromagnetic form factors, we extract the linear combination of strange form factors G{sub E}{sup s} + 0.392G{sub M}{sup s} = 0.014 {+-} 0.020 {+-} 0.010 where the first error arises from this experiment and the second arises from the electromagnetic form factor data. This paper provides a full description of the special experimental techniques employed for precisely measuring the small asymmetry, including the first use of a strained GaAs crystal and a laser-Compton polarimeter in a fixed target parity-violation experiment.
- Research Organization:
- Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
- Sponsoring Organization:
- USDOE Office of Energy Research (ER) (US)
- DOE Contract Number:
- AC05-84ER40150
- OSTI ID:
- 824555
- Report Number(s):
- JLAB-PHY-04-4; DOE/ER/40150-2623; nucl-ex/0402004; TRN: US0402126
- Resource Relation:
- Other Information: No journal information given for this preprint; PBD: 1 Feb 2004
- Country of Publication:
- United States
- Language:
- English
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