Siming Guo

Transition edge sensor (TES) have high energy resolution, which can extremely improve in various scientific experiments the energy spectrum analysis capability and have a wide range of applications in almost all fields covering the whole wave band of electromagnetic waves. The same Chinese ancient human bone sample was measured by fluorescence analysis using SDD, Si-PIN detector and TES detector. Typical representative results among the measurements of the three detectors were selected for comparative analyses. The experimental results showed that the TES detector has obvious advantages compared with the semiconductor detector, with a resolution of 21.2eV@3.69 keV, compared to 115.8 eV @ 3.69 keV and 143.9 eV @ 3.69 for SDD and Si-PIN detectors, respectively. TES detector even found some spectral lines that cannot be measured by semiconductor detectors, such as the 0.916 keV L line of Cu, L line of 2.86 keV Rh and so on. The experimental results demonstrate the TES detector’s outstanding performance in elemental spectral line detection. Compared to observations with semiconductor detectors, using X-ray TES enables clear resolution of spectral lines corresponding to elements present in the sample.

This paper presents an apparatus designed for the generation of polarized X-rays utilizing crystal Bragg diffraction techniques, which produces polarized X-rays energies within the range of 4-10 keV, facilitating the calibration of detection efficiency, energy resolution, polarization degree, and other parameters pertinent to polarized X-ray detectors. The apparatus comprises of a radiation source, a diffractive crystal, a rotating control mechanism, a detector and other components. High-precision generation of polarized X-rays can be achieved by diffracting through crystals with varying lattice constants at an angle of 45? using an X-ray tube and a Bragg diffraction apparatus. Monte Carlo simulations were conducted to evaluate air absorption effects on X-rays at varying energy levels, revealing an optimal measurement distance of 30 cm. Key metrics such as energy output, flux rate, energy resolution and mono-chromaticity for the generated polarized X-rays were evaluated through experimental measurements. The polarized X-ray flux rates were measured as: 4.135?106 m-2s-1 at 4.59 keV, 2.210?107 m-2s-1 at 6.39 keV, and 1.958?107 m-2s-1 at 10.029 keV. Monochromaticity values were: 1.48 % at 4.59 keV, 0.96 % at 6.39 keV, and 0.15 % at 10.029 keV. The apparatus is applicable to ground calibration of astronomical satellite payloads and detector development.

This study utilizes the monochromatic X-ray radiation device established by the National Institute of Metrology, China, to conduct a systematic experimental investigation of the mass attenuation coefficients of niobium, molybdenum, tantalum, and tungsten metals near their K absorption edges. The device's ability to generate continuously tunable monochromatic X-rays and accurately measure photon counts provides an ideal condition for precise mass attenuation coefficient measurements. This study employs a minimum energy step of 0.1 keV to systematically obtain the jump ratio rK and jump factor JK near the K-absorption edges of the four materials. The experimental measurements are compared with theoretical values from NIST-XCOM, NIST-FFAST, and Phy-x databases, demonstrating a consistent trend between the experimental and theoretical results, with relative deviations within acceptable limits, thereby validating the reliability of the theoretical models. An uncertainty analysis reveals a combined relative uncertainty of less than 2.7 %, indicating that the experimental results and theoretical values are in good agreement, with deviations and uncertainties within acceptable ranges. This research provides important experimental data and theoretical references for the application of monochromatic X-ray radiation devices in the field of mass attenuation coefficient measurements.

An absorber with a high absorbing efficiency is crucial for X-ray transition edge sensors (TESs) to realize high quantum efficiency and the best energy resolution. Semimetal Bismuth (Bi) has shown greater superiority than gold (Au) as the absorber due to the low specific heat capacity, which is two orders of magnitude smaller. The electroplating process of Bi films is investigated. The Bi grains show a polycrystalline rhombohedral structure, and the X-ray diffraction (XRD) patterns show a typical crystal orientation of (012). The average grain size becomes larger as the electroplating current density and the thickness increase, and the orientation of Bi grains changes as the temperature increases. The residual resistance ratio (RRR) (R_{300 K}/R_{4.2 K}) is 1.37 for the Bi film (862 nm) deposited with 9 mA/cm² at 40 °C for 2 min. The absorptivity of the 5 μm thick Bi films is 40.3% and 30.7% for 10 keV and 15.6 keV X-ray radiation respectively, which shows that Bi films are a good candidate as the absorber of X-ray TESs.