New superconducting electron cyclotron resonance ion source for RIKEN RI beam factory project

Abstract

For RIKEN radio isotope beam project, we started to construct the new superconducting electron cyclotron resonance ion source (SC-ECRIS), which has an operational frequency of 28 GHz, in 2007. The main feature of this ion source is that we can produce large size of resonance zone with six sets of solenoid coils. Before starting, we intensively studied the effect of several key parameters of ECRIS (magnetic field configuration, microwave power density, negatively biased disk) on the plasma. In this article, we describe the effect of key parameters on the plasma and detailed structure of the new SC-ECRIS.

An Ion Source’s View of Its Plasma

“…Meanwhile, superconducting ECRISes have been taken into operation worldwide, e.g., in the US (LBNL, Berkeley) [12], in Japan (Riken, Tokyo) [13] and in China (IMP, Lanzhou) [14]. These versions use 28 GHz for plasma heating, but 45 GHz and 56 GHz are already under investigation.…”

Charge Stripper Ring for RIKEN RI Beam Factory

“…This is due to the continuous performance improvements of the 28-GHz superconducting ion source [12][13][14], several innovations in the durability and quality of the charge strippers [15][16][17][18][19][20], the sophistication of the high-intensity beam operation, and steady improvements in other various accelerator components [21][22][23][24].…”

Status update of the Charge Stripper Rings project

“…Two charge stripping processes are applied to accelerate the uranium ( 238 U) beam, which is exceptionally important for rare RI beam production by in-flight fission: the uranium beam intensity, which was 0.4 pnA in 2008, is dramatically increased to 117 pnA in the fall of 2020. This is due to the continuous performance improvement of the 28 GHz superconducting ion source [12][13][14], several innovative technological developments regarding the durability and quality of charge strippers [15][16][17][18][19][20], the upgrading of the high intensity beam operation, and steady improvements in various other accelerator components [21][22][23][24][25].…”