Superconducting Super Collider silicon tracking subsystem research and development

Technical Report · Sat Dec 01 04:00:00 EST 1990

DOI:https://doi.org/10.2172/6185012· OSTI ID:6185012

Miller, W O; Thompson, T C; Ziock, H J ^[1]; Gamble, M T ^[2]

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1. Los Alamos National Lab., NM (USA)
2. Massachusetts Inst. of Tech., Cambridge, MA (USA). Dept. of Materials Science and Engineering

The Alamos National Laboratory Mechanical Engineering and Electronics Division has been investigating silicon-based elementary particle tracking device technology as part of the Superconducting Super Collider-sponsored silicon subsystem collaboration. Structural, materials, and thermal issues have been addressed. This paper explores detector structural integrity and stability, including detailed finite element models of the silicon wafer support and predictive methods used in designing with advanced composite materials. The current design comprises a magnesium metal matrix composite (MMC) truss space frame to provide a sparse support structure for the complex array of silicon detectors. This design satisfies the 25-{mu}m structural stability requirement in a 10-Mrad radiation environment. This stability is achieved without exceeding the stringent particle interaction constraints set at 2.5% of a radiation length. Materials studies have considered thermal expansion, elastic modulus, resistance to radiation and chemicals, and manufacturability of numerous candidate materials. Based on optimization of these parameters, the MMC space frame will possess a coefficient of thermal expansion (CTE) near zero to avoid thermally induced distortions, whereas the cooling rings, which support the silicon detectors and heat pipe network, will probably be constructed of a graphite/epoxy composite whose CTE is engineered to match that of silicon. Results from radiation, chemical, and static loading tests are compared with analytical predictions and discussed. Electronic thermal loading and its efficient dissipation using heat pipe cooling technology are discussed. Calculations and preliminary designs for a sprayed-on graphite wick structure are presented. A hydrocarbon such as butane appears to be a superior choice of heat pipe working fluid based on cooling, handling, and safety criteria.

• Research Organization: Los Alamos National Lab., NM (USA)
• Sponsoring Organization: DOE/AD
• DOE Contract Number: W-7405-ENG-36
• OSTI ID: 6185012
• Report Number(s): LA-12029; ON: DE91009227
• Country of Publication: United States
• Language: English

Related Subjects

440104* -- Radiation Instrumentation-- High Energy Physics Instrumentation
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
CONTROL SYSTEMS
COOLING SYSTEMS
DESIGN
ENERGY SYSTEMS
HEAT PIPES
MATERIALS TESTING
MEASURING INSTRUMENTS
PARTICLE TRACKS
RADIATION DETECTORS
SEMICONDUCTOR DETECTORS
SI SEMICONDUCTOR DETECTORS
STORAGE RINGS
SUPERCONDUCTING SUPER COLLIDER
TESTING