论文信息 - Precision Measurements of the Nucleon Strange Form Factors at<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:msup><mml:mi>Q</mml:mi><mml:mn>2</mml:mn></mml:msup><mml:mo>∼</mml:mo><mml:mn>0.1</mml:mn><mml:mtext> </mml:mtext><mml:mtext> </mml:mtext><mml:msup><mml:mi>GeV<

Precision Measurements of the Nucleon Strange Form Factors atQ2∼0.1 GeV<

We report new measurements of the parity-violating asymmetry A(PV) in elastic scattering of 3 GeV electrons off hydrogen and He-4 targets with approximate to 6.0 degrees. The He-4 result is A(PV) = (+6.40 +/- 0.23(stat) +/- 0.12(syst)) x 10(-6). The hydrogen result is A(PV) = (-1.58 +/- 0.12(stat) +/- 0.04(syst)) x 10(-6). These results significantly improve constraints on the electric and magnetic strange form factors G(E)(s) and G(M)(s). We extract G(E)(s) = 0.002 +/- 0.014 +/- 0.007 at = 0.077 GeV2, and G(E)(s) + 0.09G(M)(s) = 0.007 +/- 0.011 +/- 0.006 at = 0.109 GeV2, providing new limits on the role of strange quarks in the nucleon charge and magnetization distributions.

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