New Spin-Physics Experiments with Frozen-Spin Target at MAMI

In the physics program for the MAMI C accelerator the investigation of the spin dependent excitation spectrum of the nucleon and fundamental properties, such as the spin polarizabilities of the nucleon are an important goal. This will be tackled in the framework of the A2‐collaboration by doing double polarization experiments, using the linearly or circularly polarized energy marked photon beam in combination with a new solid state polarized target. The horizontal dilution refrigerator of the Frozen Spin Target was constructed by and is operated in close cooperation with, the Joint Institute for Nuclear Research in Dubna, Russia. The system offers both longitudinally and transversely polarized protons and deuterons. The target material, butanol and deuterated butanol, was developed and produced by the Ruhr‐University of Bochum and provides the highest degree of polarization, measured with a new NMR apparatus. The status of the experiment and preliminary results will be presented.