Estimation of output signal of dielectric microcalorimeters by X-rays incidence

In the energy dispersive X-ray spectroscopy, silicon semiconductor detectors have been used to obtain the X-ray spectrum. Recently, various types of a low temperature detector are developed for exceeding a performance of the semiconductor detector by using physical property of materials in the temperature below 1 K. Dielectric microcalorimeters are promising low temperature detectors with the excellent energy resolution. Operation principle and proto type device of the dielectric microcalorimeter are discussed for estimation of the detection signal. The out put signal is estimated for the dielectric microcalorimeter device based on the SrTiO3 material in the case of 5.9 keV X-ray detection. By means of the small thermal diffusivity, the pulse height of detection signal depends on the incident position of X-ray. In the case of the incident position beneath the top electrodes, the microcalorimeter device operated at 100 mK is predicted to exhibit the detection signal with the pulse height of 18 x 10-3VB(DC voltage applied to the device), the rise time of 50 ns and the decay time of 120 ns. (M. Suetake)