Study on data processing for x-ray spectrometer based on microcalorimeter

X-ray spectroscopy is an important method in exploring the material composition and elemental properties. Traditional spectrometers in X-ray spectroscopy include wavelength-dispersive type and semiconductors-based energy-dispersive type. The former possesses high energy resolution but low collecting efficiency and narrow spectral band coverage, while the latter is more efficient and wider in spectral range but give relatively low energy resolution. Spectrometers based on microcalorimeters serve as a new class of energy-dispersive type spectrometers which balance the performance in energy resolution, detection efficiency, and spectral coverage, making them promising in many spectroscopy applications. The superconducting transition-edge sensor (TES) is a representative class of maturely developed microcalorimeters success in array fabrication and readout. We are developing TESs-based X-ray spectrometer at ShanghaiTech University aiming at the application in advanced X-ray light source, like synchrotron radiation or free electron laser facilities. Recently, a prototype has been set up and started running in the lab. This paper introduces a systematic work on data processing with this prototype, focusing on both data acquisition and analysis. With optimization on both hardware and analysis, we have achieved resolution better than 7 eV in the range from 2 keV to 9 keV on the prototype.