Lessons Learned About Helium-Cooled Winter-Over South Pole Instrumentation

Giles Novak, January 15, 1996

This is a summary of debriefings that I conducted with three CARA winter-overs during 1995 and early 1996. One purpose of the debriefings, and the entire purpose of this document, is to understand the problems associated with running liquid-Helium-cooled instruments at Pole during Winter, so we can maximize our chances for success in this endevour.

The winter-over scientists that I debriefed are John Kovak (COBRA, Austral Winter 1994), Mike Masterman (COBRA, 1995), and Richard Chamberlin (AST/RO, 1995). Chamberlin and Kovak used liquid Helium in the Winter, and Masterman used it in the Summer but didn't use it in the Winter. In the Winter, he ran a cryogenic compressed-Helium refrigerator. Chamberlin is a postdoc, Kovac an undergraduate research assistant, and Masterman is an engineer. Chamberlin got data, Kovak and Masterman gathered useful information on Winter operations but did not get significant amounts of data.

I interviewed Kovak twice: The first time was a meeting, also with Steve Platt, in Summer 1995. This meeting resulted in E-mail to the entire COBRA team regarding telescope design. The second was a phone call in December 1995. I interviewed Masterman and Chamberlin before they left Pole after their 1995 Winter-over, and followed up with Chamberlin during a phone conversation in January 1996.

The only aspects of these interviews that I will discuss are those related to running dewars.


I divide this report into four categories:

(A) Reliability:

(B) Serviceability:

(C) Ease-of-Maintenace:

(D) Cryogen Consumption:


Last revision January 15, 1996. Contact novak@belmont.astro.nwu.edu or jdotson@nwu.edu