WG2015
BNL, Upton, Long Island, New York, USA
Transverse beam break up instability is one of the main limited factor to achieve high average current operation in Energy Recovery Linacs. 30 GeV ERL is considered as an electron source for electron ion collider (eRHIC) at BNL. The full scale ERL consist of 6 passes up and 6 passes dawn through 2 SRF linacs with ~2.5 GeV gain energy each. The average current required for eRHIC is 50 mA from injector. The full scale machine has to be capable to operate at various top energies (from 5 to 30 GeV). We will present results of BBU threshold calculation based on new design BNL3 SRF cavity with HOMs dumping for different top energy settings and discuss possible scenarios to satisfy the requirements.
WG3001
BNL, Upton, Long Island, New York, USA
Stony Brook University, Stony Brook, USA
A six-pass ERL will provide 50-mA electron beam for collisions with hadrons in eRHIC. The two main linacs are based on the BNL-3 704 MHz 5-cell elliptical SRF cavities. At full energy of 30 GeV, the length of each linac will reach 200 m. In addition to the main ERL, two smaller single-pass ERLs will be used as 1) 600-MeV injector into the main ERL, and 2) source of 70-mA electron beam for coherent cooling of the hadron beam. This paper describes the design of the SRF cavity and cryomodule, requirements to for the RF system, and plans for prototyping various components.