The proton, a state of three quarks bound by the strong force of QCD, also has a ``sea'' of quark-antiquark pairs that includes strange quarks. A fundamental issue is how much these strange quarks contribute to the charge radius and magnetic moment of the proton. A particularly clean experimental technique for isolating these effects is measuring parity-violation asymmetry A_PV in the elastic scattering of polarized electrons from protons. From A_PV, we can cleanly extract the strangeness contributions to the elastic form factors, G_E^s and G_M^s. The strange form factors provide a direct measure of the strangeness contribution to the proton's radius and magnetic moment. In Hall A at the Thomas Jefferson National Accelerator Facility (JLab), the HAPPEX collaboration measured A_PV at the kinematic point (\langle\theta_\mathrm lab\rangle= 12.3^\circ and \langle Q^2\rangle=0.48 (GeV/c)^2). From our data, we can extract the combination G_E^_s+0.39 G_M^s=0.023\pm0.034(stat)\pm0.022(syst)\pm0.026(\delta G_E^n), where the last error results from the uncertainty in G_E^n. The result places a significant limit on the size of the effects of strangeness in the nucleon. The relative ease with which we were able to measure a small asymmetry at JLab bodes well for the future of experiments measuring parity-violating amplitudes.

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