Speaker
Description
In upgrading the present SOLEIL ring, it has been decided to introduce longitudinal bunch-by-bunch feedback (LFB) in addition to the already existing transverse feedback (TFB), since it was evaluated that the new normal conducting fundamental RF cavities will have a non-zero risk of exciting longitudinal coupled-bunch instabilities due to their higher-order-modes (HOMs). SOLEIL II also plans to use bunch-lengthening harmonic cavities (HCs) to improve the Touschek lifetime performance, which may trigger complex LCBIs, such as periodic transient beam loading (PTBL) or fast mode-coupling instabilities, which tend to appear when the HCs are tuned to the limit of lengthening. This study aims to pursue the performance limit of LFB against possible LCBIs. Using the multibunch tracking code mbtrack2, instability growth rates and required LFB damping rates has been studied. The paper also presents beam-based test converting the currently operating TFB system to LFB by utilizing the stripline kicker for energy kicks.
| In which format do you inted to submit your paper? | LaTeX |
|---|