International Workshop on Future Linear Colliders 2026

Demonstration of an accelerating gradient of >50 MV/m on 650 MHz single cell cavities

Not scheduled

20m

KEK

Oral presentation (remote) High Gradient RF Techniques High Gradient RF Techniques

Speaker

Dr Vijay Chouhan (Fermilab)

Description

Achieving accelerating gradients in 650 MHz superconducting radio frequency (SRF) cavities is important for future high-performance accelerators. This work presents the RF performance of two single-cell 650 MHz niobium cavities processed using electropolishing procedures optimized for 650 MHz geometry and a low-temperature bake. Both cavities achieved accelerating gradients above 50 MV/m, demonstrating that this performance level can be reproduced. One cavity reached 53.3 MV/m with a quality factor of 1.6E+10, corresponding to a peak surface magnetic field of about 198 mT. The second cavity reached 51 MV/m with quality factor of 2.2E+10 following similar surface processing. These results demonstrate the potential of the developed processing approach to reliably produce high-gradient 650 MHz cavities.