Author: Pöplau, G.
Paper Title Page
WEP01 Simulations for Ion Clearing in an ERL 143
 
  • G. Pöplau, A. Markoviḱ, U. van Rienen
    Rostock University, Faculty of Computer Science and Electrical Engineering, Rostock, Germany
  • A. Meseck
    HZB, Berlin, Germany
 
  Funding: supported by BMBF under contract no. 05K10HRC
Energy Recovery Linacs (ERLs) being the most promising candidates for next-generation light sources put very high demands on preservation of beam brightness and reduction of beam losses. Thus, it is mandatory to avoid the impact of ionized residual gas considered as a source for instabilities in accelerators. Recently, we have presented simulations for the clearing of ionized residual gas with electrodes performed with an upgraded version of software package MOEVE PIC Tracking [1] which is being currently further developed to model the interaction of the ions with the electron beam in presence of external electromagnetic potentials such as the field of clearing electrodes. The tracking code allows for studies on clearing times for electrodes with different voltage as well as detailed studies of the behavior of the ions in the environment of the electrodes. In this paper we take further steps to study possible designs of clearing electrodes. Especially, we will consider the influence of different gas mixtures on clearing times and possible configurations for the clearing electrodes. We use parameters planned for BERLinPro as an example for our studies.
[1] G. Pöplau, A. Meseck, U. van Rienen, Simulation of the Behavior of Ionized Residual Gas in the Field of Electrodes, IPAC 2012, New Orleans.
 
 
WEP02 Numerical Studies on the Influence of Fill Patterns on Ion Clouds 146
 
  • A. Meseck
    HZB, Berlin, Germany
  • G. Pöplau, U. van Rienen
    Rostock University, Faculty of Computer Science and Electrical Engineering, Rostock, Germany
 
  Funding: supported by BMBF under contract no. 05K10HRC
Energy Recovery Linacs (ERLs) are the most promising candidates for next-generation light sources now under active development. An optimal performance of these machines requires the preservation of the high beam brightness generated in the injector. For this, the impact of the ionized residual gas on the beam has to be avoided as it causes instabilities and emittance growth. Obviously, the vacuum chamber has to be cleared out of ions but as the potential of the electron beam attracts the ions, it is not enough to install vacuum pumps. One measure for ion clearing are gaps in the bunch train long enough that the ions have time to escape the force of the bunch potential. In this paper, we present numerical studies of the behavior of an ion cloud that interacts with a bunch train. Especially, we consider different distributions for the particles in the bunch, different fill patterns and several mixtures of ions in the residual gas. The simulations are performed with the package MOEVE PIC Tracking. The presented numerical investigations take into account the parameters of the ERL BERLinPro with the objective to deduce appropriate measures for the design and operation of BERLinPro.