Q DROP TENDENCY OF HALF-WAVE RESONATOR CAVITY

초록

Half-wave resonator superconducting cavities (HWRs) have been fabricated and tested. HWRs have been installed in the low energy section of the LINAC and being ready to be cooled down for the next step. All HWR cavities have been completely tested in two ways: vertical test and horizontal test. For the vetical test, HWRs were tested both at 4.2 K and 2.1 K cryogenic surroundings although the operating temperature is 2.1 K. Good cavity having higher quality factor than that of the target value showed the Q<inf>0</inf> drop tendency of 2.1 K was very similar to that of 4.2 K. However, in many cases, Q<inf>0</inf> drop tendency of 2.1 K was not similar with 4.2 K, rather Q<inf>0</inf> decreased more rapidly than 4.2 K which means the surface resistance of the cavity rapidly increased at 2 K surrounding. In this study, we will report that various Q<inf>0</inf> results of HWRs and discuss their Q<inf>0</inf> drop tendencies as a function of temperature, 2.1 K and 4.2 K along with field emission. © 2022 Proceedings - Linear Accelerator Conference, LINAC. All rights reserved.