Importance

Loading Importance Indicators...

Abstract

A cryostat for operation with liquid helium, comprises a primary chamber (2) with a main region (4) and a pot region (6) for containing a bath (8) of liquid helium-4, primary inlet means (12) for introducing liquid helium-4 and primary outlet means (14) for releasing gaseous helium-4, the primary inlet means comprising a transfer line (16) extending into the primary region. The cryostat is configured for operation under a continuous supply of liquid helium-4 and at a reduced helium-4 pressure, whereby gaseous helium-4 is pumped off through the outlet means. The primary chamber comprises a baffle structure (18) arranged between the pot region and the main region, the baffle structure defining at least one flowpath (20a, 20b) for the flow of gaseous helium-4, each flowpath forming a detoured connection between the pot region and the main region. A method for operating the cryostat comprises a cool-down phase followed by a stationary phase. In the cool-down phase, liquid helium-4 is supplied from an external reservoir through the primary inlet means into the pot region thereby evaporatingly cooling the latter until a bath of liquid helium-4 starts to accumulate on a bottom surface of the pot region. In the stationary phase, a bath temperature of liquid helium-4 is maintained by regulating the inlet flow of liquid helium-4 and/or regulating the rate of pumping off gaseous helium-4 through the primary outlet means, and optionally by controlled heating.

Loading the Abstract Image...

First Claim