The XRS system - the first cryogenic X-ray detector in orbit

The X-ray Spectrometer, XRS on board the ASTRO-E Satellite is a cryogenic X -ray detector system utilizing a micro calorimeter array of 32 pixels opera ting at 60 mK. An energy resolution of about 12 eV (FWHM) has been obtained across the array in the ground calibration measurements. We adopted a uniq ue three-stage cryogenic system consisting of solid neon, liquid helium, an d an adiabatic de-magnetization refrigerator to obtain a long cryogenic lif etime in orbit, The design of the neon tank was optimized to obtain about 2 yr of the neon lifetime, which determines the lifetime of the whole cryoge nic system. (C) 1999 Elsevier Science B.V. All rights reserved.