FRP009  ポスター④  10月21日 会議室P 13:00-15:00
SuperKEKB LERにおけるインピーダンスモデリング
Impedance modeling in SuperKEKB LER
 
○石橋 拓弥,周 徳民(高エネ研・加速器),ミリョラーティ マウロ(ローマ・ラ・サピエンツァ大学),柴田 恭,阿部 哲郎,飛山 真理,照井 真司(高エネ研・加速器)
○Takuya Ishibashi, Demin Zhou (KEK accelerator laboratory), Mauro Migliorati (Sapienza Universita di Roma), Kyo Shibata, Tetsuro Abe, Makoto Tobiyama, Shinji Terui (KEK accelerator laboratory)
 
In the Low Energy Ring (LER) for positrons in SuperKEKB, an unexpected vertical beam-size blow-up has occurred at approximately 1.0 mA/bunch. This bunch current threshold depends on apertures of vertical collimators in the ring, thus this single bunch instability can be caused by the impedance. The threshold in the actual machine is smaller than that in the simulations by approximately 60% or more, so we have reconstructed the impedance model in the ring. This paper summarizes the updated results of impedance calculations for components.