Difference: FJPPLAccelerateurRD (17 vs. 18)

Summary:
In F.Y. 2017, KEK and CEA started the R&D for power coupler in SRF accelerator. First of all, the effect of the ultrasonic rinsing on copper plating was investigated. Consequently, in some cases, it turned out that the copper plating was peeled out, and in the other cases, there were white marks on the copper plating samples. This result was presented in LCWS2017. As next step, the residual resistivity ratio (RRR) is being investigated between KEK and CEA, because RRR is essential for the quality control of copper plating. Some types of copper plating samples were already fabricated, and tested. This preliminary result will be presented in LINAC2018. From F.Y. 2018, LAL newly joined this collaboration. In future, the effect of the ultrasonic rinsing will be investigated for the STF-type power couplers by collaboration between KEK and LAL. And also, impurity of copper plating will be investigated. Recently, KEK obtained some successful results in the measurement of secondary electron emission coefficient for some ceramic samples. For these ceramic samples, the rinsing effect will be investigated by collaboration of Japan-France.

French members:
W. Kaabi, H. Guler, C. Arcambal, E. Cenni

Japanese members:
Y .Yamamoto, E. Kako, A. Yamamoto, S. Michizono, T. Matsumoto, H. Sakai

References:
[1] Y. Yamamoto, et al., LCWS2017, Strasbourg, France (2017).
[2] Y. Yamamoto, et al., US-Japan ILC Cost Reduction Workshop, KEK, Japan (2017).
[3] Y. Yamamoto, et al., THPO097, LINAC2018, Beijing, China (2018).