Separate cooling systems for individual components of a multi-segmented detector cryostat

Abstract

Position of the copper braids in the ATC cryostat is characterized in that the housings of the preamplifiers (4) can dissipate their heat to the copper cooling finger above the taper (2) through their own cooling braid (1).

Description

[0001] Germanium detectors must be cooled to below -180°C for operation. If the FETs in the first preamplifier stage are also cooled (=> faster rise time, better signal-to-noise ratio), both components must be cooled by a cold finger via the LN2 reservoir. The FETs consume 20-25 mW of power during operation. This heat must be dissipated. Separating the cooling paths allows for a well-defined temperature for the detectors, as well as for the FETs separately. State of the art:

[0002] Previously, cooling was achieved by a copper cooling finger mounted centrally in the cryostat. However, this solution is difficult to control in complex detector systems with large numbers of cooled preamplifiers (FETs). Inventive step:

[0003] The invention involves separating the cooling system and providing dedicated heat sinks, specifically for the preamplifiers. This concept was first implemented in the AGATA cryostat and has proven successful. 1. The temperature of the detectors can be stabilized during operation in the optimal range of approximately -180 °C. 2. The temperature of the FETs (first preamplifier stage) can be stabilized to the ideal temperature of approximately -130 °C by selecting the cooling copper conductors. 3. Such a separate cooling system allows the operation of a large number of preamplifier FETs independent of the operating temperature of the corresponding Ge detector. Advantages of the invention: 1. Improved cooling efficiency: Separating the cooling systems and providing dedicated heat dissipation for the preamplifiers results in more uniform and controllable cooling. 2. Increased reliability: Targeted cooling and better ground connection of the preamplifiers reduces the risk of losses of the very sensitive FETs. 3. Flexibility: The system can be adapted to different detector systems and spectrometers, allowing for broad applicability. Industrial applicability:

[0004] The invention is applied in the production of any asymmetric AGATA triple cryostat and is commercially marketed. The invention is suitable for use in comparable cryostats for other applications. List of names: 1 Dedicated copper braids that provide cooling for the preamplifiers. 2 Rejuvenation of the copper cooling. 3 Encapsulated GE detectors. 4 Preamplifier housings (FET)

Claims

[1] Position of the copper braids in the ATC cryostat characterized by that the housings of the preamplifiers (4) can dissipate their heat to the copper cooling finger above the taper (2) through their own cooling braid (1). [2] Material selection of the cooling braids (1) characterized by that pure electrolytic copper is used, which ensures optimal heat transfer. [3] Material construction of the cooling braids (1) characterized by that flexible copper strands are used, which enable mechanical decoupling between the housings of the preamplifiers and the copper cooling fingers and thus dampen vibrations within the ATC cryostat even at an operating temperature below -180°C.

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