By applying a transition edge sensor (TES) as the thermometer in an X-ray microcalorimeter, the intrinsic energy resolution is expected to be significantly improved. The extremely low intrinsic noise allows us to operate the calorimeter at temperatures as high as one can obtain by pumping liquid 3He (approximately 0.3 K) and still achieve an energy resolution comparable to conventional semiconducting microcalorimeters operating at approximately 60 mK (ΔE approximately 10 eV FWHM). Taking this advantage into account, we are developing a titanium/gold bilayer TES calorimeter fabricated on a silicon wafer. The transition temperature is about 0.5 K. We have succeeded in detecting X-ray photons from 3 to 25 keV, which proves that this TES calorimeter works in a wide energy range. The energy resolution is, however, still much worse than we expected -550 eV (FWHM) at 5.9 keV. This is because the design parameters are not optimized. Several approaches to improve the performance are described.
|Number of pages||4|
|Journal||Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment|
|Publication status||Published - 7 Apr 2000|
|Event||8th International Workshop on Low Temperature Detectors (LTD-8) - Dalfsen, Neth|
Duration: 15 Aug 1999 → 20 Aug 1999