Update for E12-07-104: Measurement of the Neutron Magnetic Form Factor at High Q Using the Ratio Method on Deuterium

In JLab Experiment E12-07-104 we intend to dramatically extend the reach of our understanding of a fundamental feature of the neutron; its magnetic form factor GnM . The elastic electromagnetic form factors(EEFFs) describe the distribution of charge and magnetization inside the nucleon at low Q and probe the quark structure at higher Q. This experiment is part of a broad program at JLab to measure the EEFFs, map the internal landscape of the nucleon, and test non-perturbative Quantum Chromodynamics (QCD) and QCD-inspired models of the nucleon (see NSAC LongRange Plan [1]). The measurement will cover the range Q = 3.5 − 14.0 GeV with systematic uncertainties less than 3%. Statistical uncertainties will be about 3% in the highest Q bin in this range and significantly less at lower Q. The anticipated range and systematic uncertainties of the experiment are shown in Figure 1. The reduced magnetic form factor GnM/(μnGD) is plotted versus Q where μn is the neutron magnetic moment and GD = 1/(1 +Q /Λ) is the dipole form factor with Λ = 0.71 GeV. We used the recent parameterization of the world’s data on GnM in Ref [10] to predict the reduced form factor. Also shown are selected world’s data for GnM including Co-spokesperson Contact person