Updated Model of the Resistive Wall Impedance for the Main Ring of J-PARC

The resistive wall impedance is one of the major contributors of the impedance in the Main Ring of J-PARC. The present model assumes round chambers of stainless steel with perfect magnet boundary conditions for its surroundings. This work presents the model of the resistive wall impedances taking into account the different chamber geometries of Main Ring, the materials and more realistic surroundings. The models were benchmarked with measurements of the coherent tune shift of the Main Ring of J-PARC. The simulation of beam instabilities is a helpful tool to evaluate potential threats against the machine protection of the high intensity beams.