| Paper |
Title |
Page |
| MOPCH169 |
High Pressure Rinsing Water Jet Characterization
|
460 |
| |
- D. Sertore, E. Cavaliere, M. Fusetti, P. Michelato, C. Pagani, P. Pierini
INFN/LASA, Segrate (MI)
|
|
| |
High pressure rinsing is widely used as the final wet step in the high field superconducting cavities production. The interaction of an high speed ultra pure water jet with the niobium surface depends on various parameters such as water pressure, water throughput, treatment duration, cavity rotation speed, etc. In this paper we illustrate a simple technique for the characterization of water jet parameters based on the momentum transfer between the water jet and a load cell. The jet profile and its dependence on water pressure as well as the force exerted by the jet on the surface are easily measured. Moreover a portable apparatus has been set up and the information gathered in different laboratories will be used for a quantitative comparison of the different HPR systems. These measurements allow to study the correlation of the jet parameters with the effects (surface status, oxide formation, corrosion, etc) of the water interaction with the niobium surface. Furthermore a new analysis, based on the luminescence induced on transparent dielectric samples, is used for confirmation of the water jet structure.
|
|
| WEPLS051 |
Dark Current Investigation of TTF and PITZ RF Guns
|
2493 |
| |
- L. Monaco, P. Michelato, C. Pagani, P. Pierini, D. Sertore
INFN/LASA, Segrate (MI)
- J.H. Han, S. Schreiber
DESY, Hamburg
- M. Krasilnikov, F. Stephan
DESY Zeuthen, Zeuthen
|
|
| |
The dark current is one of the limiting factor in the operation of RF guns at high gradient. The continuous request of higher brilliance sources and further emittance minimization, leads to apply higher gradients in the RF gun cavity, with the consequence of a significant dark current production. In this context we set up a collaborative effort to identify the dark current sources in the gun, in order to discriminate between the gun and cathode contribution. A critical analysis and organization of dark current measurements, taken during the operation of TTF and PITZ guns, with several cathodes operated at different accelerating fields and solenoids focusing, is presented. Potential areas of improvement are also discussed, together with a possible associated program.
|
|
| WEPLS052 |
High QE Photocathode at FLASH
|
2496 |
| |
- D. Sertore, P. Michelato, L. Monaco, C. Pagani
INFN/LASA, Segrate (MI)
- J.H. Han, S. Schreiber
DESY, Hamburg
|
|
| |
The RF gun-based photoinjector of the VUV-FEL/TTF at DESY continues to use high quantum efficiency (QE) photocathodes produced at LASA, Milano. To study the photocathode behavior during beam operation, an online QE monitoring tool has been installed. In this paper, we present the hardware and software setup for the online QE measurement and the results so far obtained. The measured QEs are usually higher than at TTF phase 1. We compare the QE values taken in the RF gun with data measured just after production with a continuous UV light source.
|
|