| Paper | Title | Page |
|---|
| TUP28 | 1.3 GHz Cavity Weld to Helium Vessel | 192 |
| | - A. Schmidt, A. Matheisen, H. Kaiser, W. Menck, G. Weichert
DESY Hamburg
| |
| | At DESY Hamburg superconducting accelerator units
(Cavities) are under development for the FLASH
accelerator and the XFEL project. For accelerator
application each cavity is equipped with an individual
Helium vessel and cooled by bath cooling with Helium at
2K [1]. The improvements of cavity performance like
gradient and quality factors require improvements on the
processes of completion the He tank as well. An overview
on the sequences and processes for tank welding for the
DESY 1.3 GHz Cavities will be given. | |
| TUP30 | Update on Cavity Preparation for High Gradient Superconducting Multicell Cavities at DESY | 196 |
| | - B. vanderHorst, A. Matheisen, B. Petersen, S. Saegebarth, P. Schilling
DESY Hamburg
| |
| | For the proposed XFEL Project at DESY about 850
Cavities will accelerate the electron beam. The
resonators have to provide average acceleration
gradient of 23, 6 MV/m [Ref.:1]. In order to reach that
gradient reproducibly in a medium scale production,
several preparations methods and surface treatments
are under study at DESY. Beside the standard fine
grain niobium material in use up to now, nine cell
resonators made from large grain niobium are under
investigation since 2006. We present the different
approaches in surface preparation procedures for fine
and large grain niobium and the related cavity results. | |
| TUP31 | Update on EP Experiences at DESY with the Electro Polishing Process at DESY 1.3 GHZ | 200 |
| | - M. Schmoekel, A. Matheisen, B. Petersen, N. Steinhau-Kuehl, H. Weitkamper
DESY Hamburg
| |
| | Since several years electro-polishing (EP) of
superconducting resonators is one of the major
preparation techniques in use for high gradient
superconducting resonators. At DESY the EP facility is
operational since mid of 2003. About 150 resonators have
been polished in this infrastructure since. Typical process
data, a maintenance plan and reliability of components
installed in the DESY apparatus as well as actual RF test
results of resonators will be presented. For the XFEL
project the industrialization of the electro polishing
processes is started. A status report of the industrialization
will be given. | |
| TUP33 | Update on the JRA1 Project Results of Electro-Polishing of Multi-Cell Super Conducting Resonators | 204 |
| | - N. Steinhau-Kuehl, R. Bandelmann, A. Matheisen, H. MoralesZimmermann, M. Schmoekel
DESY Hamburg - E. Palmieri, V. Rampazzo
INFN
| |
| | Under the contract RII3-CT-2003-506395 of the
European Union improvement on the electro-polishing
(EP) of multi cell resonators are made. Several methods
to improve resonator performances are studied.
Improvement of electrode shape, simulated by numerical
computer codes and test set ups are presented. With
respect to reproducible cavity performances and
industrialization of the EP process, a study for quality
control by acid management is started. An automated EP
system is developed at INFN Legnaro / Italy and within
the collaboration of Legnaro and DESY this automated
steering will be integrated into the DESY EP facility. We
will report on the status of the WP 5.2.2.and the progress
of the transfer of the automated EP. | |
| WEP17 | Considerations on the third harmonic RF of the European XFEL | 481 |
| | - E. Vogel, M. Dohlus, M. Huening, K. Jensch, A. Matheisen, W. -D. Moeller, A. Schmidt, W. Singer
DESY Hamburg - H. Edwards, E. Harms, T. Khabiboulline
Fermilab
| |
| | Ultra short bunches with high peak current are required for the creation of high brilliance coherent light in the x-ray range in undulators. At the European x-ray free electron laser (XFEL) they will be obtained by a two stage bunch compression scheme based on off the rf field crest acceleration and transverse magnetic chicanes. The deviation of the rf field's sine shape from a straight line leads to long bunch tails and reduce peak current. This effect will be eliminated by adding a third harmonic rf system. The paper surveys the basic principle for the third harmonic rf, the most relevant design parameters, the actual status of beam physical examinations and potential concepts for the technical realization. | |
| WEP66 | High pressure rinsing system studies | 664 |
| | - D. Sertore, M. Fusetti, P. Michelato, C. Pagani
INFN Milano-LASA - T. Higo, J. Hong, K. Saito
KEK - G. Ciovati, T. Rothgeb
JLab - A. Matheisen, N. Krupka
DESY
| |
| | High pressure rinsing (HPR) is a key process for the
surface preparation of high field superconducting cavities.
HPR water jets used in different laboratories have been
characterized measuring the transferred momentum
between the water jet and a target connected to a load cell.
The information taken during these measurements,
combined with HPR process parameters, allow
calculating new significant measurable variables such as
the jet power, the deposited energy on the cavity surfaces
and the pressure. | |