JACoW is a publisher in Geneva, Switzerland that publishes the proceedings of accelerator conferences held around the world by an international collaboration of editors.
TY - CONF AU - Mitsuka, G. AU - Ikeda, H. AU - Mitsuhashi, T.M. ED - Zimmermann, Frank ED - Tanaka, Hitoshi ED - Sudmuang, Porntip ED - Klysubun, Prapong ED - Sunwong, Prapaiwan ED - Chanwattana, Thakonwat ED - Petit-Jean-Genaz, Christine ED - Schaa, Volker R.W. TI - Renovation of the SR Beam Profile Monitors with Novel Polycrystalline Diamond Mirrors at the SuperKEKB Accelerator J2 - Proc. of IPAC2022, Bangkok, Thailand, 12-17 June 2022 CY - Bangkok, Thailand T2 - International Particle Accelerator Conference T3 - 13 LA - english AB - SR beam profile monitors are fundamental to perform the stable beam operation of SuperKEKB. To suppress thermal deformation of SR extraction mirrors–a long-standing issue in SR monitors–, we developed platinum coated diamond mirrors in 2019. The diamond mirrors are made with optical-quality polycrystal-diamond-substrate with extremely large thermal conductivity, and have a size of 20 mm (W) x 30 mm (H) x 2 mm (D). Surface flatness better than λ/5 was observed in an optical testing with a laser interferometer. The diamond mirrors have been installed in HER and LER in 2020 summer and 2021 summer, respectively. Through irradiation for an year at the beam current greater than 800 mA, no significant deformation of the diamond mirrors has been observed. In this talk, we will discuss the design, construction, and optical testing of the polycrystal diamond mirrors. Also beam measurements performed using an interferometer, a coronagraph, a streak camera, and a fast gate camera will be presented. PB - JACoW Publishing CP - Geneva, Switzerland SP - 313 EP - 315 KW - extraction KW - optics KW - laser KW - radiation KW - synchrotron DA - 2022/07 PY - 2022 SN - 2673-5490 SN - 978-3-95450-227-1 DO - doi:10.18429/JACoW-IPAC2022-MOPOPT031 UR - https://jacow.org/ipac2022/papers/mopopt031.pdf ER -