検索対象:     
報告書番号:
※ 半角英数字
 年 ~ 
 年

How to make extraction electrode current lower than beam and corresponding beam qualities in J-PARC cesiated RF-Driven H$$^{-}$$ ion source 66 mA operation

J-PARC Cs添加型高周波駆動H$$^{-}$$イオン源66mA運転時の引き出し電極電流をビームより少なくする方法とその時のビーム性能

上野 彰 ; 大越 清紀 ; 池上 清*; 高木 昭*; 神藤 勝啓  ; 小栗 英知 

Ueno, Akira; Okoshi, Kiyonori; Ikegami, Kiyoshi*; Takagi, Akira*; Shinto, Katsuhiro; Oguri, Hidetomo

J-PARC Cs添加型高周波駆動H$$^{-}$$イオン源を66mAビーム強度で安定に運転するために、ビームと同時に引き出される電子が主成分の引き出し電極電流(I$$_{EE}$$)を最小化する条件を調べた。ロッドフィルター磁場(RFF)、Cs密度、軸磁場補正(AMFC)を最適化することで、約40mAとこれ迄の運転条件時の1/4程度のI$$_{EE}$$で、安定運転できることが分かった。特に、40Gauss程度の少ないAMFCによるI$$_{EE}$$の縮小効果(約1/3)は、最も有効であった。この条件での95%ビーム横方向エミッタンスは、強めたRFFと高めたCs密度の影響で、約24%悪化していた。測定結果を基に、安定運転とビーム性能の両立が図られる。

In order to operate the J-PARC cesiated rf-driven H$$^{-}$$ ion source with a beam intensity of 66 mA stably, the conditions to minimize the extraction electrode current (I$$_{EE}$$), whose main component is the electron current co-extracted with the beam, were investigated. The 66 mA H$$^{-}$$ ion beam with a low I$$_{EE}$$ of about 40 mA, which was one-fourth of that in the ordinal operation, were stably extracted by optimizing a rod-filter-field (RFF), a cesium (Cs) density and an axial magnetic field correction (AMFC). Especially, the AMFC of only 40 Gauss had the largest I$$_{EE}$$ reduction of about one-third. The corresponding 95 % beam transverse normalized rms emittances were degraded about 24 % due to the higher RFF and Cs density. The source will be operated in the conditions to compromise the stability and the beam quality by the investigated results.

Access

:

- Accesses

InCites™

:

Altmetrics

:

[CLARIVATE ANALYTICS], [WEB OF SCIENCE], [HIGHLY CITED PAPER & CUP LOGO] and [HOT PAPER & FIRE LOGO] are trademarks of Clarivate Analytics, and/or its affiliated company or companies, and used herein by permission and/or license.