HAPPEX: Strange Quarks in the Proton and 4He
- Thomas Jefferson National Accelerator Facility (United States)
HAPPEX results from our 2005 run for the parity-violating asymmetry A PV in elastic scattering of 3 GeV electrons off hydrogen and 4He targets at <{theta}lab> {approx_equal} 6.0 deg. are presented. The 4He result is APV (+6.40 {+-} 0.23 (stat) {+-} 0.12 (syst)) x 10-6. The hydrogen result is APV = (-1.58 {+-} 0.12 (stat) {+-} 0.04 (syst)) x 10-6. The asymmetry for hydrogen is a linear combination of G{sub E}{sup s} and G{sub M}{sup s}, the strange quark contributions to the electric and magnetic form factors of the nucleon, respectively, and that for 4He is a function of G{sub E}{sup s} alone. The measurements imply G{sub E}{sup s} + 0.09G{sub M}{sup s} = 0.007 {+-} 0.011 {+-} 0.006 at <Q2> = 0.109 GeV2 and G{sub E}{sup s} = 0.002 {+-} 0.014 {+-} 0.007 at <Q2> = 0.077 GeV2.
- OSTI ID:
- 21064017
- Journal Information:
- AIP Conference Proceedings, Vol. 915, Issue 1; Conference: 17. international spin physics symposium, Kyoto (Japan), 2-7 Oct 2006; Other Information: DOI: 10.1063/1.2750880; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0094-243X
- Country of Publication:
- United States
- Language:
- English
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