Study of Temperature Influence on Timepix2 Energy Measurements

AbstraktAbstract

In this study, we examine the temperature dependence of a Timepix2 (v1) detector (256× 256 pixels, 55 μm pixel pitch) coupled to a 500 μm thick silicon sensor. Measurements were performed with γ-photons 59.5 keV and α-particles 5.5 MeV in vacuum over a stabilized temperature range of -20 °C to 80 °C. Two different readout systems were used to verify that the response of the Timepix2 detector was not affected by the readout electronics. In both normal and adaptive gain modes, the detector demonstrated excellent stability in Time-over-Threshold (ToT) based energy measurements, with relative deviations of peak positions remaining below 4% across the temperature range from -20 °C to 80 °C. Digital-to-Analog Converter (DAC) voltage measurements revealed a significant temperature dependence of the DAC Ikrum, which compensates for threshold shifts and enables accurate ToT readings. In adaptive gain mode, a systematic shift of approximately 0.6% per 10 °C was observed in absolute ToT accuracy.

In this study, we examine the temperature dependence of a Timepix2 (v1) detector (256× 256 pixels, 55 μm pixel pitch) coupled to a 500 μm thick silicon sensor. Measurements were performed with γ-photons 59.5 keV and α-particles 5.5 MeV in vacuum over a stabilized temperature range of -20 °C to 80 °C. Two different readout systems were used to verify that the response of the Timepix2 detector was not affected by the readout electronics. In both normal and adaptive gain modes, the detector demonstrated excellent stability in Time-over-Threshold (ToT) based energy measurements, with relative deviations of peak positions remaining below 4% across the temperature range from -20 °C to 80 °C. Digital-to-Analog Converter (DAC) voltage measurements revealed a significant temperature dependence of the DAC Ikrum, which compensates for threshold shifts and enables accurate ToT readings. In adaptive gain mode, a systematic shift of approximately 0.6% per 10 °C was observed in absolute ToT accuracy.