The Cryogenic System for the SLAC E158 Experiment

Technical Report · Thu Jul 12 00:00:00 EDT 2001

DOI:https://doi.org/10.2172/784992· OSTI ID:784992

Weisend, John G ^[1]

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1. SLAC

E158 is a fixed target experiment at SLAC in which high energy (up to 48 GeV) polarized electrons are scattered off the unpolarized electrons in a 1.5 m long liquid hydrogen target. The total volume of liquid hydrogen in the system is 55 l. The beam can deposit as much as 700 W into the liquid hydrogen. Among the requirements for the system are: that density fluctuations in the liquid hydrogen be kept to a minimum, that the target can be moved out of the beam line while cold and replaced to within 2 mm and that the target survive lifetime radiation doses of up to 1 x 10{sup 6} GY. The cryogenic system for the experiment consists of the target itself, the cryostat containing the target, a refurbished CTI 4000 refrigerator providing more than 1 kW of cooling at 20 K and associated transfer lines and valve boxes. This paper discusses the requirements, design, construction, testing and operation of the cryogenic system. The unique features of the design associated with hydrogen safety and the high radiation field in which the target resides are also covered.

• Research Organization: Stanford Linear Accelerator Center, Menlo Park, CA (US)
• Sponsoring Organization: USDOE Office of Energy Research (ER) (US)
• DOE Contract Number: AC03-76SF00515
• OSTI ID: 784992
• Report Number(s): SLAC-PUB-8917
• Country of Publication: United States
• Language: English

Related Subjects

43 PARTICLE ACCELERATORS
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
CONSTRUCTION
COOLING SYSTEMS
CRYOGENIC FLUIDS
CRYOSTATS
DESIGN
ELECTRONS
HYDROGEN
LIFETIME
PERFORMANCE TESTING
RADIATION DOSES
REFRIGERATORS
SAFETY
TARGETS
VALVES