TUOB04 　ビームダイナミクス・加速器理論/加速器技術（真空）①　 10月18日 会議室B 17:00-17:20

SuperKEKBにおける銅溶射ビームパイプの電子密度の測定

Measurement of electron density in copper thermal spray beam pipe in SuperKEKB

○姚 慕蠡（総研大），末次 祐介，柴田 恭，石橋 拓弥（KEK, 総研大），久松 広美，金澤 健一，白井 満，照井 真司（KEK）

○Mulee Yao (SOKENDAI), Yusuke Suetsugu, Kyo Shibata, Takuya Ishibashi (KEK, SOKENDAI), Hiromi Hisamatsu, Ken-ichi Kanazawa, Mitsuru Shirai, Shinji Terui (KEK)

In the previous studies, we confirmed that the copper thermal spray coating has low secondary electron yield (SEY). The lowest δmax (the maximum SEY within scanning) after conditioning reached ~0.7. We produced a straight aluminum beam pipe with copper thermal spray coating using optimized conditions and installed it in the positron ring of SuperKEKB, in order to observe the effect of the coating on reducing the electron cloud. Its surface resistance was also measured as a reference for whether it can be used in accelerators. The results show that the electron density in the copper thermal spray beam pipe was much smaller than that in the bare aluminum beam pipe and was comparable to that of the TiN-coated beam pipe.