Karlsruhe 2011 – scientific programme

Parts | Days | Selection | Search | Updates | Downloads | Help

T: Fachverband Teilchenphysik

T 83: RF / Instabilitäten

T 83.9: Talk

Tuesday, March 29, 2011, 18:50–19:05, 30.22: 020

Electron cloud effects in SIS-18 and SIS-100 — •Fedor Petrov^1,2, Oliver Boine-Frankenheim^1,2, and Thomas Weiland¹ — ¹Technische Universität Darmstadt, Institut für Theorie Elektromagnetischer Felder (TEMF) Schlossgartenstrasse 8, 64289 Darmstadt, Germany — ²Gesellschaft für Schwerionenforschung (GSI) GmbH, Planckstraße 1, D-64291 Darmstadt, Germany

Electron cloud build-up and associated instabilities are studied in simulations under conditions relevant to SIS-18 and to the projected SIS-100 heavy ion synchrotrons. In both rings coasting beams are foreseen during slow extraction of the beam. Trapped electrons could lead to a reduction of the extraction efficiency. We present the results of electron cloud studies for bunched and for coasting beams. In these two regimes the main production mechanisms are significantly different. For coasting beams the most important mechanism is residual gas ionization, for bunched beam the main source of electrons is secondary emission. In the case of coasting beams electrons are generated in the vicinity of the beam center and a two-stream instability may occur for the projected intensities.Electron clouds due to bunched beams are of concern in SIS-100 because no special coating of the stainless steel beam pipe is presently foreseen. Finally we also discuss experimental studies of electron cloud generation in SIS-18.