Calculation of field configurations of the electrostatic septum and massless septum magnet for the slow extraction system of the JHF main ring

Since accelerating beam intensity is enormous in the JHF synchrotron, even small beam losses during the slow extraction leads to unacceptable level of radiation. We set a criterion such that tolerable beam loss in the slow extraction process should be less than 1% of the averaged beam current of 10 μA. We have examined the field configurations of the electrostatic septum and the massless septum magnet, respectively. The calculations of electrostatic and magnetic fields were carried out by the computer code POISSON. (author)