A modern Q-meter system to measure the polarization of solid polarized targets

摘要

Solid polarized targets are widely used in nuclear and particle physics experiments. Polarization measurements for these targets are normally performed using nuclear magnetic resonance (NMR). The Liverpool Q-meter was developed in the late 1970s and became the de facto standard for these NMR-based measurements. However, it has become increasingly difficult to obtain the required number of Q-meter channels, as the components have become obsolete. The Los Alamos National Laboratory (LANL) high energy nuclear physics (HENP) group has developed a new NMR-based Q-meter system, building upon the basic Liverpool design. The new Q-meter introduces several improvements, such as remote tuning and compact design, while being less costly to produce. These improvements have the potential to increase the accuracy of the polarization measurements, thereby reducing the experimental systematic uncertainties. This modern Q-meter has been successfully tested with both polarized proton and deuteron targets.