Speaker
Description
Timepix3 hybrid pixel detectors [1] are widely used in applications requiring precise radiation spectrometry, including space instrumentation [2], high-energy and nuclear physics [3] or neutron detection [4, 5], where detectors are frequently exposed to varying thermal conditions. Temperature fluctuations can influence the spectrometric response, affecting both the accuracy of energy measurements and the energy resolution.
The temperature dependence of Timepix3 detectors equipped with the Katherine readout system and various semiconductor sensors (Si, GaAs, CdTe, and 4H-SiC) has been previously investigated over a temperature range from −20 °C to 80 °C and for photon energies between approximately 8 and 60 keV. It was shown that while the energy resolution remains relatively stable across the investigated conditions (with Δσ within 1 keV), a systematic temperature-dependent shift of the photopeak position occurs. This effect, which directly impacts the accuracy of energy determination, becomes more pronounced at elevated temperatures, particularly above 60 °C, reaching deviations of up to −17% (observed for the 4H SiC sensor at 80 °C) [6].
To mitigate this effect, a temperature compensation method was developed for each sensor material based on a unified mathematical framework. The approach relies on establishing a linear relationship between the measured and true photon energies at each temperature, followed by modeling the temperature dependence of the linear regression parameters using second-order polynomial functions. By combining these relationships, a temperature-dependent correction function is obtained, enabling compensation of the observed spectral shifts.
The proposed compensation methods allow accurate reconstruction of photon energies across the investigated temperature range without the need for repeated recalibration at each operating temperature, using a well-defined mathematical correction procedure.
[1] T. Poikela, et al., JINST 9 (2014), C05013
[2] C. Granja, et al., JINST 17 (2022) C03019
[3] B. Bergmann, et al. Nucl. Instrum. Methods Phys. Res. A, 978 (2020), 164401
[4] C. Granja, et al., JINST 18 (2023) P01003
[5] P. Rubovič, et al., Nucl. Instrum. Methods Phys. Res. A, 985 (2021), 164680
[6] N. Kurucova, et al. . Presentation #1665, In 2025 IEEE NSS MIC RTSD, Yokohama, Japan, 1 -8 November, 2025. RTSD-08-05. Abstract at p. 1524.
The authors acknowledge funding from the Slovak Research and Development Agency (Research Projects APVV-22-0382 and DS-FR-24-0020) and from the EU NextGenerationEU through the Recovery and Resilience Plan for Slovakia under the project No. 09I05-03-V02-00073.