CLASSE NEWS | 16 May 2012
The ILC 9-cell cavity "ACCEL9" processed by VEP at Cornell achieved 38MV/m with Qo of 9.0e9. This is the first 9-cell cavity that achieved ILC base-line specification (Qo=1.0e10 at 31.5MV/m, Qo=8.0e9 at 35MV/m) by VEP in the world. This achievement is a big breakthrough on VEP R&D for ILC's Alternative Concept Design (ACD). Cornell's SRF group has been developed VEP for many years. So far VEP'ed cavity performance was limited by too much Q-slope above 25 MV/m. For ACCEL9, we minimized VEP removal based on previous VEP studies with single- and multi-cell cavities at Cornell. The first trial was already successful and achieved the ILC specifications. To demonstrate reproducibility and a high yield, R&D on VEP will be continued.
Cornell Vertical Electro-Polishing of SRF cavities achieves ILC base-line specifications
Vertical-test results of ACCEL9 at 2.0 K in the pi-mode. Red dots show the cavity performance; two X dots indicate the ILC baseline specifications.