Positron acceleration to 200 MeV

220 MeV is the energy that has to be obtained in routine operation. A standard 12m girder with SLED II can give 220 MeV minus a few percent due to not riding at the crest of the wave. In order to have the 200 MeV with only one girder, a klystron at full power all the time would be required - kept brand new. Then, for safety it is necessary to use two klystrons as designated in the SLC design. Having two klystrons gives freedom for the choice of the best arrangement. Since there will be excess rf power, it can be traded against higher gradient, shorter waveguides, larger apertures (lower shunt impedence)

L'ACCÉLÉRATEUR LINÉAIRE A ÉLECTRONS DE SACLAY

L'exposé donne les performances actuellement obtenues lors des essais de cet accélérateur fonctionnant à grand cycle utile (2 % maximum), grande intensité (jusqu'à 60 mA crête) et une énergie maximale de l'ordre de 600 MeV à courant nul. L'accent est porté sur les divers facteurs contribuant à la finesse du spectre en énergie (< 1 %) et à la grande stabilité des caractéristiques du faisceau de puissance moyenne élevée (ordre de 100 kW).The accelerator is designed to operate at high duty cycle (2 % maximum), high intensity (up to 60 mA peak current) and maximum energy of around 600 MeV at zero current. Results are given of the various tests performed, with emphasis on the main factors contributing to the narrow energy spectrum (< 1 %) and to the high stability of the characteristics of the powerful beam (about 100 kW mean power)