Minutes of the CLIC Meeting - 20 June 2003
Minutes of the CLIC Meeting - 20 June 2003
| Agenda: |
Analyses, measurements and experiments
performed at EST-SM for the CLIC project |
| Speakers: |
Gonzalo Arnau Izquierdo, Sergio Calatroni
and Morten Kildemo |
The seminar will give an overview of three EST-SM activities related to the CLIC project. The observations made on irises mounted and conditioned in the CTFII structure will be presented. Scanning electron microscopy and energy dispersive X-ray analysis on the molybdenum and tungsten irises will illustrate the surface modifications (melting, evaporation, cracks....) induced by the operation.
The first results of a laser irradiation experiment aimed at simulating the fatigue behaviour of copper and tungsten under cyclic thermomechanical load will be presented. The effect of the cycling on the materials has been monitored by SEM as a function of the number of cycles.
Finally, examples of the evolution of the field emission current as a function of increasing electric field up to "vacuum" breakdown will be presented and the interpretation will be discussed in terms of surface modifications/conditioning. The distribution of the field enhancement factor BETA as a function of the surface history, for copper niobium and tungsten surfaces will be shown.
This contributions are part of the current effort of EST-SM for the CLIC project together with brazing, surface analysis, surface cleaning and galvanic coating.
copy of his transparencies (pdf format)Sergio presented the results of the laser pulsed heating experiment.
copy of his transparencies (pdf format)Morton presented the spark test experiments where field emission currents and a capacitor discharge are measured. The capacitor is partly discharged by field emission until the FE cuts off or discharged completely by a spark.
copy of his transparencies (pdf format)