Simulations of Electron-Cloud Current Density Measurements in Dipoles, Drifts, and Wigglers at CesrTA

A core component of the Cesr-TA research program at Cornell is to fully understand the electron cloud effect through the use of simulation programs that have been developed to predict the growth of the cloud and its interaction with the beam. As a local probe of the electron cloud, several segmented retarding field analyzers (RFAs) have been installed in CesrTA in dipole, drift and wiggler regions. Using these RFAs, the energy spectrum of the time-average electron cloud current density striking the walls has been measured for a variety of bunch train patterns, with different bunch currents, beam energies, emittances, and bunch lengths, and for both positron and electron beams. This paper will compare these measurements with the predictions of simulation programs.