I got a nice phone call from Robert Norton of the Cryo group, who had read my halog entry. His answer is "No, unless the beam will be off for extended times (of order a day or more) then they prefer to have the cryogenic demands be steady - this aids in monitoring/debugging cryo issues. Even adjusting the J/T valve very slowly can add instabilities to the overall cryogenic system. Indeed, even if we do have an extended down time, we (meaning the target operator) should call cryo group and consult before adjusting the J/T significantly.
To consult the appropriate cryo group experts, one should call Robert Norton at x7331 or Mathew Wright at x7722.
Thanks to Robert for reading the halog, and answering my question!
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