OVERVIEW AND STATUS OF THE 12 GeV CRYOGENIC SYSTEM UPGRADE AT JLAB

As part of the planned Jefferson Laboratory's electron accelerator (CEBAF) power upgrade, ten additional superconducting RF cryomodules will be added to its accelerator linacs. Although physically the same size as each of the original 40 linac cryomodules, each new cryomodule will have approximately 4 times the acceleration power. To support the additional cryomodule heat loads generated, the existing 2 K, 4600 W Central Helium Liquefier (CHL) plant capacity will be doubled to a total of 9200 W at 2 K plus 24,000 W at 35 K for shield loads. The specified base line process cycle has been modeled after the laboratory's 'Ganni Helium Cycle' process technology. In addition, a fourth physics experimental 'Hall D' will be constructed which will have an additional stand alone 200 W at 4 K helium cryogenic plant. In October of 2008, Jefferson Laboratory (JLab) received approval for project 'Critical Decision 3' construction phase status from the US Department of Energy. An overview of the planned cryogenic systems and current design baseline as it relates to operations will be presented.