Mirion U-Style cryostats have a vertically-oriented detector chamber located at the end of a horizontal arm extending from the side of the Dewar or cooler.
This configuration excludes the preamplifier and other hardware from the inner cavity of the lead shield and eliminates all line-of-sight streaming paths to the detector element. These features contribute significantly to the overall background reduction of the counting system.
The U-Style cryostat configuration has a lower center of gravity for the detector and shield as compared to a standard vertical configuration which may make it attractive for mobile applications as in trailer- or ISO container-based counting facilities. Additionally the U-style cryostat configuration allows installing the detector in systems where there is no room under the shield to place the Dewar or cooler.
The standard length of the horizontal arm is 12 in. (305 mm) measured from the flange of the preamplifier service body to the detector center line. This length makes the U-style cryostat compatible with both 4 in. (102 mm) and 6 in. (152 mm) thick Mirion lead shields.
The standard configuration comes with a radial O-ring seal. A metal face seal is available as an option on detectors with a 3.0 in. (76 mm) diameter endcaps only. Metal seals are more rugged and, in general, provide a longer life time of the detector vacuum.
End cap dimensions depend on detector size. The chart shows the typical efficiency range vs. end-cap diameter. End cap lengths are also greater for larger detectors. Consult the factory if end-cap size is critical in your application.