Speaker
Michael Green
(Michigan State University)
Description
The two cyclotron gas stopper superconducting solenoid coils were designed to be cooled down and to be kept cold in the range 4.25 K to 4.6 K using three pulse tube coolers per coil. These coolers are designed to produce from 1.4 to 1.7 W per cooler when the cooler first stage is at about 40 K. The cyclotron gas stopper coils are designed that they can be separated while cold, but unpowered. The magnet coils were cooled down separately in 2014. Room temperature helium gas from bottles was liquefied into the magnet cryostats. The magnet temperature at the end of the cool-down was 4.45 K for one coil and 4.6 K for the other at the end of the cool-down. The coil-down time for the coils was over three times longer than expected. The time to liquefy the helium is the magnet cryostats was also longer than expected. The reasons for the disparity between the calculated cool-down time and measured cool-down time are explained in the paper. Steps that could be taken to speed up the cool-down time are discussed.
Author
Michael Green
(Michigan State University)
Co-authors
Dr
Al Zeller
(Michigan State University)
Dr
Shailendra Chouhan
(Michigan State University)
