CERN Accelerating science

Article
Title	Injection Options for 12 GeV CEBAF Upgrade
Author(s)	Kazimi, Reza ; Benesch, Jay ; Chao Yu Chiu ; Grames, Joseph M ; Krafft, Geoffrey A ; Tiefenback, Michael ; Yunn, Byung C ; Zhang, Yuhong
Affiliation	(Jefferson Lab, Newport News, Virginia)
Publication	2005
In:	21st IEEE Particle Accelerator Conference, Knoxville, TN, USA, 16 - 20 May 2005, pp.2911
Subject category	Accelerators and Storage Rings
Abstract	Jefferson Lab is planning to upgrade the CEBAF accelerator from 6 to 12 GeV. In order to achieve this, the beam energy at injection into the main accelerator needs to increase from 67 MeV to either 123 or 134 MeV depending on the location of the new experimental hall relative to the accelerator. The present 100 keV electron source and beam formation to 5 MeV will remain unchanged; however, the present accelerating cryomodules in the injector cannot reach the higher injection energies. Consequently, two options for attaining these energies are considered: (1) replacing the present injector cryomodules with new, higher gradient cryomodules, or (2) re-circulating the beam through the existing cryomodules to achieve the necessary energy gain in two passes. In this paper we present simulation results and list the advantages and disadvantages of these two options.