Vertical test results for ERL 9-cell cavities for compact ERL project

コンパクトERL計画のための9セル空洞の縦測定結果

梅森 健成*; 古屋 貴章*; 阪井 寛志*; 佐藤 昌史*; 篠江 憲治*; 沢村 勝; Cenni, E.*

Umemori, Kensei*; Furuya, Takaaki*; Sakai, Hiroshi*; Sato, Masato*; Shinoe, Kenji*; Sawamura, Masaru; Cenni, E.*

ERLの試験施設としてコンパクトERLが進められている。この計画の第1段階として主空洞で30MVの加速を行う。9セル空洞が2台製作され、種々の表面処理がなされた。最終の電界研磨においては低電流密度モードで行われた。2台の空洞について縦測定が行われ、加速電界は25MV/mを、Q値は20MV/mで110を達成した。フィールドエミッションは14と22MV/mで起こり始めた。両空洞ともERLの要求仕様を満たしている。縦測定の詳細をX線と温度測定の結果とともに発表する

The Compact ERL project, which is a test facility of ERL, is ongoing in Japan. At the first step of this project, main linac cavities accelerate electron beams by 30 MV. Two 9-cell cavities were fabricated for main linac cryomodule. A series of surface treatments were applied for the cavities. For the final EP, current density was selected to be relatively low. Vertical tests were performed for both cavities. Their field successfully reached to 25 MV/m, without any field limitation. The Q-values were more than 110, even at 20 MV/m. Field emission on-sets were to be 14 and 22 MV/m, for each cavity. Both cavities satisfied requirements for ERL main linac cavity. Details of vertical tests, with X-ray and temperature mapping data, are shown, in this paper.