Seminar FO

    An overview of the form factor programme of the A1 Collaboration at

    MAMI is given. Results on the electromagnetic form factors of the

    proton measured with elastic electron scattering at four-momentum

    transfers Q^2 between 0.003 and 2 (GeV/c)^2 are reported, which

    allow extraction of the electric and magnetic radii of the proton.

    Data for scattering on the deuteron have also been taken and their

    analysis is ongoing.

    A novel technique to measure the electric form factor of the proton

    at very low Q^2 using initial state radiation is presented and

    results from a pilot experiment are shown.

    The design of a neutron recoil polarimeter for measurement of the

    electric form factor in a future double-polarisation experiment is

    presented.