ALMA MEMO NO. 437 Miniature, Modular Heat Sinks for ALMA Cryostats
نویسندگان
چکیده
Proposed receiver cartridges for ALMA may utilize up to 96 wires for SIS mixer bias, IF amplifier bias, thermometry and other functions [1]. To reduce heating of the mixer block and minimize the load on the 4 K refrigerator stage, heat sinks will be required on the 80 K, 12 K and 4 K stages. The present concept for the receiver cartridges requires disassembly of each thermal stage to effect repairs. Heat sinks utilizing connectors simplify disassembly, thus improving the mean time to repair. The large number of wires and connections will require a simple, reliable heat sink capable of being mass-produced for the expected 64 receiver cartridges.
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