Analytical Sciences


Abstract − Analytical Sciences, 24(1), 11 (2008).

X-ray Microcalorimeter Based on Superconducting Transition Edge Sensors
Masashi OHNO,*,** Hiroyuki TAKAHASHI,** R. M. Thushara DAMAYANTHI,** Yasuhiro MINAMIKAWA,*** and Fumiakira MORI**
*Precursory Research for Embryonic Science and Technology (PRESTO), Japan Science and Technology Agency, 5 Sanbancho, Chiyoda, Tokyo 102-0075, Japan
**Department of Nuclear Engineering and Management, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-8656, Japan
***Department of Bioengineering, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-8656, Japan
We have tried to realize an X-ray imaging spectrometer based on the superconducting transition edge sensor (TES) with high energy resolution, a large pixel array, a relatively high absorption efficiency and a high count rate. Our single pixel of Ir/Au TES achieved an excellent energy resolution of 9.4 eV for 5.9 keV X-rays. We have also proposed a pixellated array of Ir-TES where we slightly modify the bias point of each pixel and identify the pixel from the response function of each pixel. Our 10-pixel device, where all pixels are parallel biased, obtained 13 eV (FWHM) at 3 keV energy resolution and 80 µm position resolution. So far, we could successfully operate a 20-pixels device. Further, we are now trying to improve the count rate and the absorption efficiency of TESes, by developing our original new TES geometry which having a radiation absorber that self-adjusts the operating temperature.