The Status of the University of Michigan Polarized Proton Target

The University of Michigan Solid Polarized Proton Target (PPT) was built in the late 1980's; it uses irradiated NH3 at 5 T and 1 K. It was used in a 1990 experiment in a 24 GeV intense proton beam at the Brookhaven AGS, where its average polarization was about 85%. It was recently upgraded for the 70 GeV SPIN@U-70 experiment at IHEP-Protvino in Russia. Improvements were made to its superconducting magnet, its refrigerator, and its NMR and microwave systems.