Transition-edge microcalorimeters for X-ray space applications

In an European Space Agency funded research project, our goal is to develop microbolometer technology for X-ray and far-infrared detection for ESA's f uture scientific missions. We report results on the X-ray calorimeter, whic h is based on the superconducting transition of the Ti/Au thermometer strip at about 200 mK. Incident X-rays heat up a Bi absorber, deposited on top o f the 400 mu m x 400 mu m thermometer. The temperature rise of the absorber is measured as a change of the thermometer current with a SQUID operating at 1 K. (C) 2000 Elsevier Science B.V. All rights reserved.