Silicon drift detectors are the core sensors for next-generation space-based X-ray detection, where precise efficiency calibration is crucial for both astronomical observation and radiation monitoring. In this study, calibration was performed using a ground-based monochromatic X-ray calibration facility that employs Bragg diffraction to establish the energy linearity and detection efficiency of an silicon drift detectors detector. A linear relationship between incident energy and channel number was observed, with a correlation coefficient of R² = 0.9987. Monte Carlo simulations were used to model the physical structure of the detector and to calculate its detection efficiency curve across the 2-40 keV range. Comparison with experimental measurements revealed the minimum deviation of 0.53 % at 10 keV and the maximum deviation of 4.77 % at 14 keV. In the 7-32 keV range, measured and simulated detection efficiencies closely matched, with the detector achieving a peak detection efficiency of 94.5 % at approximately 9 keV. The energy resolution of the detector was also calibrated, and a nonlinear curve fitting relationship between intrinsic energy resolution and energy was established, highlighting the variation in monochromaticity with energy. These results validate the feasibility and superiority of using continuously tunable mono-energetic X-rays for silicon drift detectors calibration. This approach lays the groundwork for future space astronomy missions and provides traceable physical references for in-orbit data.
Li et al. (2026) studied this question.