Adaption of an array of metallic magnetic calorimeters for the use at the CRYRING electron target

Microcalorimeters for the high-resolution detection of X-rays are an important part of the instrumentation at the storage rings ESR and CRYRING. Within the ErUM-FSP T05 APPA, an array of metallic magnetic calorimeters will be equipped for the application at the transverse electron target of CRYRING and CRYRING@ESR. The final goal is to provide a fully functional system of magnetic microcalorimeters which is specifically adapted to the electron target. To realize this, a 3He/4He dilution refrigerator was redesigned to host an array of magnetic metallic calorimeters. In the current project, to make optimal use of the available solid angle, the side arm where the detectors are mounted will be extended by about 300 mm. In this process, special care has to be taken to optimize the thermal design to maintain stable operating conditions at an operating temperature of below 50 mK.  In addition, electronic noise caused by vibrations from the pulse tube cooler has to be kept as small as possible.