| Paper | Title | Page |
|---|
| TUP74 | Progress of the Test Cavity Program for the European XFEL | 327 |
| | - A. Brinkmann, J. Iversen, D. Reschke, W. Singer, X. Singer, K. Twarowski, J. Ziegler
DESY Hamburg
| |
| | Two main goals of the test cavity program for the
European XFEL are the qualification of alternative
niobium vendors and the investigation of the capabilities
of large grain niobium for large-scale nine-cell cavity
production. About 25 1.3 GHz single-cell cavities of
TESLA shape have been completed at Accel Instruments
and DESY. Alternative vendors for high purity fine-grain
niobium are ITEP Giredmet, Cabot, Ningxia and Plansee.
The in-house fabricated cavities have been tested after
800C firing and final electropolishing (EP) treatment. All
cavities exceed gradients of 35 MV/m at high Q-values.
For the large grain cavities of high RRR Heraeus niobium
gradients up to 41 MV/m have been achieved. The
performance after final chemical etching (BCP) is
compared to EP for several cavities. | |