We present results obtained with detectors consisting of dielectric absorber crystals and superconducting phase transition thermometers made of Ir/Au bilayers. With a 31 g sapphire crystal and an Ir/Au thermometer operated at 45 mK we have obtained an energy resolution of 220 eV (FWHM) for collimated 5.9 ke V X-rays. To explain the measured pulse shapes we have developed a model which includes the effect of non-thermal phonons. Results obtained previously with a 18 g Si absorber and an Ir/Au thermometer with broad transition allowed checking this model over a wide temperature range. A heater experiment performed with this calorimeter provides further support of our model.
ASJC Scopus subject areas
- Atomic and Molecular Physics, and Optics
- Materials Science(all)
- Condensed Matter Physics