Recent improvements and future upgrades of the j-parc main ring kicker magnet systems

J-PARC Main Ring provides a high-intensity proton beam to the long baseline neutrino oscillation experiment (T2K). Increasing the beam intensity to improve the sensitivity of the CP violation study in the neutrino sector, both shorter repetition cycle and higher beam current are required. As a part of the upgrade project, both injection and fast-extraction (Fx) kicker magnet systems have been improved. A new quick charging power supply of the modulator for the Fx kicker magnet was developed and deployed to shorten the charging period from 1.8 sec to 0.2 sec. Non-inductive ceramic resistors are used as the impedance-matching terminator for the injection kicker magnet. A temperature rise of the termination resistor due to the beam induced current was measured, and the average power was estimated to optimize the number of the resistors connected in parallel. Numerical simulation of the thermal behavior of the resistors was carried out, and the results were compared with the measurements. This paper represents the performance of the new charging unit and the design of the termination resistor.