摘要 |
A cryostat configuration for keeping liquid helium, comprising an outer jacket (2) accommodating a helium container (5), a neck pipe (3) which is filled with gaseous helium during operation, and a refrigerator (1; 1b), wherein the outer jacket (2), the helium container (5) and the neck pipe (3) delimit an evacuated chamber (9) which surrounds the helium container (5); and wherein the refrigerator (1; 1b) has a cooling finger (4) which has a condensation body (15; 15b) in the region of the lower end of the neck pipe (3), is characterized in that the condensation body (15; 15b) is partially surrounded by a condensation chamber (16; 16b) which has a first lower opening (17) to permit draining of liquid helium, and a second opening which communicates with a lower end of a gas supply pipe (18), wherein the upper end of the gas supply pipe (18) terminates in the region of the upper end of the neck pipe (3). This improves the thermal properties of the cryostat configuration. In particular, the convection flow inside the neck pipe (3) is controlled.
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