Precise measurement of the neutron magnetic form factor G(M)n in the few-GeV2 region.

The neutron elastic magnetic form factor G n has been extracted from quasielastic scattering from deuterium in the CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson Lab. The kinematic coverage of the measurement is continuous over a broad range, extending from below 1 (GeV/c)2 to nearly 5 (GeV/c)2 in four-momentum transfer squared. High precision was achieved by employing a ratio technique in which many uncertainties cancel, and by a simultaneous in-situ calibration of the neutron detection efficiency, the largest correction to the data. Neutrons were detected using electromagnetic calorimeters and time-of-flight scintillators. Data were taken at two different electron beam energies, allowing up to four semi-independent measurements of G n to be made. The dipole parameterization is found to provide a good description of the data for Q 2 > 1 (GeV/c) 2 .