Thermal Detectors As X-Ray Calorimeters: Theoretical And Experimental Results And Data Processing Techniques

We report measurements on the energy resolution of germanium X-ray calorimeters for the energy range 1-50 keV. The detector we use is a modified infrared bolometer which is currently operated at 3He temperatures (0.31K) and is capable of attaining a FWHM of 172 eV for 5.9 keV X-rays. We have identified and characterized two types of event which can contaminate the spectrum of the bare germanium calorimeter. The first type is due to photons absorbed in the indium soldered contacts of the detector. The second type is due to β-particles striking the detector. The theoretical performance of such a device has been modelled by considering the individual noise sources that limit the energy resolution. We also present a discussion concerning the post-processing of data which employs both the techniques of matched filtering and maximum entropy method deconvolution.