[Halld] Hall D Solenoid Status

[Eugene Chudakov]

The solenoid was cooled down in January, after the modifications to
the cooling system had been done. The purpose of the modifications was
to employ the thermosyphon effect.

Since then, the magnet stayed at 1200A for about 2.5 months,
interrupted by a couple of trips of the power supply. During the last
week the magnet stayed at 1345A, 6.5 days in total. The test, planned
to last 7 days, was interrupted by another trip of the power supply.

In summary, the magnet is proven to be stable at 1200A and likely is
stable up to 1350A. We do not know yet if a year-long stay at 4K
would result in ice build-up somewhere in the vacuum volume on the
Helium vessel, which could make a "thermal short" and increase the
local heat load.

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Eugene Chudakov
phone (757) 269 6959  fax (757) 269 6331
Thomas Jefferson National Accelerator Facility
12000 Jefferson Ave, STE 4,
Newport News, VA 23606 USA