Longitudinal acceptance measurement at an electron storage ring

Abstract

The longitudinal acceptance of the BESSY II storage ring has been measured. To our knowledge, such a measurement has never been performed in electron storage rings. The study is also motivated by the fact that for future diffraction limited light sources a couple of longitudinal injection schemes were proposed recently. In these injection schemes, the energy and/or timing of the injection beam is shifted, resulting in a large synchrotron oscillation amplitude of the injected beam. It is, therefore, of importance to reveal whether we can evaluate the longitudinal acceptance precisely when we design a storage ring with a longitudinal injection scheme. The experimental results showed a good agreement to the acceptance evaluated through the accelerator model, including the special feature arising from the synchrotron radiation. We also found that, as a by-product, the bunch length of the injected beam can be obtained from the acceptance measurement data. The result is in good agreement with the design value of the injector booster synchrotron.

Single-shot measurement of longitudinal phase space beam profile in an electron storage ring

“…Beam manipulation in the longitudinal phase can be used to generate coherent radiation (Ratner & Chao, 2010) and beam dynamics in the longitudinal phase space to enable exploration of a new injection scheme (Kim et al, 2019;Aiba et al, 2015;Jiang et al, 2016;Jiang & Xu, 2018;Kuske et al, 2020). These goals invoke a need to measure the longitudinal beam profile.…”