Quality Factor Enhancement of 650 MHz Superconducting Radio-Frequency Cavity for CEPC
Source abstract
Abstract
Medium-temperature (mid-T) furnace baking was conducted at 650 MHz superconducting radio-frequency (SRF) cavity for circular electron positron collider (CEPC), which enhanced the cavity unloaded quality factor (Q0) significantly. In the vertical test (2.0 K), Q0 of 650 MHz cavity reached 6.4 × 1010 at 30 MV/m, which is remarkably high at this unexplored frequency. Additionally, the cavity quenched at 31.2 MV/m finally. There was no anti-Q-slope behavior after mid-T furnace baking, which is characteristic of 1.3 GHz cavities. The microwave surface resistance (RS) was also studied, which indicated both very low Bardeen–Cooper–Schrieffer (BCS) and residual resistance. The recipe of cavity process in this paper is simplified and easy to duplicate, which may benefit the SRF community.
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Research context
OpenAlex topics: Particle accelerators and beam dynamics · Particle Accelerators and Free-Electron Lasers · Superconducting Materials and Applications
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Affiliations
Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China
Key Laboratory of Particle Acceleration Physics & Technology, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China
Center for Superconducting RF and Cryogenics, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China
School of Nuclear Sciences and Technology, University of Chinese Academy of Sciences, Beijing 100049, China
References (16)
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