Measurements of the deuteron and proton magnetic form factors at large momentum transfers

Measurements of the deuteron elastic magnetic structure function {ital B}({ital Q}{sup 2}) are reported at squared four-momentum transfer values 1.20{le}{ital Q}{sup 2}{le}2.77 (GeV/{ital c}){sup 2}. Also reported are values for the proton magnetic form factor {ital G}{sub {ital M}{ital p}}({ital Q}{sup 2}) at 11 {ital Q}{sup 2} values between 0.49 and 1.75 (GeV/{ital c}){sup 2}. The data were obtained using an electron beam of 0.5 to 1.3 GeV. Electrons backscattered near 180{degree} were detected in coincidence with deuterons or protons recoiling near 0{degree} in a large solid-angle double-arm spectrometer system. The data for {ital B}({ital Q}{sup 2}) are found to decrease rapidly from {ital Q}{sup 2}=1.2 to 2 (GeV/{ital c}){sup 2}, and then rise to a secondary maximum around {ital Q}{sup 2}=2.5 (GeV/{ital c}){sup 2}. Reasonable agreement is found with several different models, including those in the relativistic impulse approximation, nonrelativistic calculations that include meson-exchange currents, isobar configurations, and six-quark configurations, and one calculation based on the Skyrme model. All calculations are very sensitive to the choice of deuteron wave function and nucleon form factor parametrization. The data for {ital G}{sub {ital M}{ital p}}({ital Q}{sup 2}) are in good agreement with the empirical dipole fit.