Introducing an 8-GeV booster synchrotron between RCS and MR at J-PARC; One possible option toward a multi-MW output beam power from MR

Hotchi, Hideaki  ; Harada, Hiroyuki  ; Yamamoto, Masanobu   ; Igarashi, Susumu*; Koseki, Tadashi*; Sato, Yoichi*

Now the J-PARC accelerators (Linac, 3GeV RCS, 50GeV MR) are in transition from the initial beam commissioning phase to the final stage aiming for the design output beam power of 1 MW from RCS and 0.75 MW from MR; RCS is to start 1-MW beam tuning from October 2014 after completing the linac upgrade, and MR aims at 0.75 MW within the next 3 years by introducing new main magnet power supplies with the faster cycling time. In view of such current situation, we have started discussions for the future J-PARC accelerator concept toward a Multi-MW output beam power. In this paper, we discuss the feasibility for the introduction of a new 8-GeV booster synchrotron between RCS and MR as one possible option toward a Multi-MW output beam power from MR, in combination with the RCS beam power upgrade from 1 MW to 2 MW.