Abstract
A 1kW refrigerator-liquefier for the Japanese Hydrogen Bubble Chamber was constructed and test operations with the chamber have been carried out for three times. In the first run, the refrigerator-liquefier which is Simple Linde type was confirmed that it could afford about 60 liters of liquid hydrogen per hour or the equivalent refrigerant. In the later two runs, the bubble chamber was cooled down to the liquid hydrogen temperature at the rate of less than 5°K per hour and filled up with 220 liters of liquid hydrogen. Many bubble chamber photographs were taken under the various thermodynamical conditions. An automatic bubble chamber temperature control system which regulates the direct two-phase hydrogen flow from the refrigerator-liquefier is now under testing.
