Precision Measurements of the Nucleon Strange Form Factors at Q{sup 2}{approx}0.1 GeV{sup 2}
- Florida International University, Miami, Florida 33199 (United States)
- California State University, Los Angeles, Los Angeles, California 90032 (United States)
- College of William and Mary, Williamsburg, Virginia 23187 (United States)
- Argonne National Laboratory, Argonne, Illinois 60439 (United States)
- University of Massachusetts Amherst, Amherst, Massachusetts 01003 (United States)
We report new measurements of the parity-violating asymmetry A{sub PV} in elastic scattering of 3 GeV electrons off hydrogen and {sup 4}He targets with <{theta}{sub lab}>{approx_equal}6.0 deg. . The {sup 4}He result is A{sub PV}=(+6.40{+-}0.23(stat){+-}0.12(syst))x10{sup -6}. The hydrogen result is A{sub PV}=(-1.58{+-}0.12(stat){+-}0.04(syst))x10{sup -6}. These results significantly improve constraints on the electric and magnetic strange form factors G{sub E}{sup s} and G{sub M}{sup s}. We extract G{sub E}{sup s}=0.002{+-}0.014{+-}0.007 at <Q{sup 2}>=0.077 GeV{sup 2}, and G{sub E}{sup s}+0.09G{sub M}{sup s}=0.007{+-}0.011{+-}0.006 at <Q{sup 2}>=0.109 GeV{sup 2}, providing new limits on the role of strange quarks in the nucleon charge and magnetization distributions.
- OSTI ID:
- 20861616
- Journal Information:
- Physical Review Letters, Vol. 98, Issue 3; Other Information: DOI: 10.1103/PhysRevLett.98.032301; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 0031-9007
- Country of Publication:
- United States
- Language:
- English
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