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 - Nishiwaki, M.
AU - Akai, K.
AU - Furuya, T.
AU - Kobayashi, T.
AU - Mitsunobu, S.
AU - Morita, Y.
AU - Okada, T.
ED - Saito, Kenji
ED - Xu, Ting
ED - Sakamoto, Naruhiko
ED - Lesage, Ana
ED - Schaa, Volker R.W.
TI - Calibration of SRF Cavity Voltage by Measurement of Synchrotron Frequency in SuperKEKB
J2 - Proc. of SRF2021, East Lansing, MI, USA, 28 June-02 July 2021
CY - East Lansing, MI, USA
T2 - International Conference on RF Superconductivity
T3 - 20
LA - english
AB - Eight SRF cavity modules, which have been operated in KEKB for more than ten years, are stably operating also in SuperKEKB. As for calibration of the cavity voltage Vc, non-negligible discrepancy was observed between the results obtained from two different methods: one is using external Q value (Q_{ext}) of pickup ports, and the other is using loaded Q value (QL) of the cavities. The discrepancy comes from inaccuracy of power measurement in high power RF system and uncertainty of the Q_{ext} or QL values. In order to solve the discrepancy by improving the accuracy of the calibration for each individual cavity, we investigated a method by measuring synchrotron frequency fs of stored beam. With this method, Vc calibration can be performed without affected by inaccuracy of high-power measurement or uncertainty of the Q_{ext} or QL values. The fs measurement studies were carried out in SuperKEKB. With these studies, Vc calibration was obtained with a high accuracy of about 1%. The results are applied to the SuperKEKB operation.
PB - JACoW Publishing
CP - Geneva, Switzerland
SP - 376
EP - 381
KW - cavity
KW - factory
KW - operation
KW - SRF
KW - pick-up
DA - 2022/10
PY - 2022
SN - 2673-5504
SN - 978-3-95450-233-2
DO - doi:10.18429/JACoW-SRF2021-TUPFAV002
UR - https://jacow.org/srf2021/papers/tupfav002.pdf
ER -