Personal Dosimetry in Direct Pulsed Photon Fields With the Dosepix Detector

Abstract

First investigations regarding dosimetric properties of the hybrid, pixelated, photon-counting Dosepix detector in the direct beam of a pulsed photon field (RQR8) for the personal dose equivalent Hp(10) are presented. The influence quantities such as pulse duration and dose rate were varied, and their responses were compared to the legal limits provided in PTB-A 23.2. The variation of pulse duration at a nearly constant dose rate of about 3.7 Sv/h shows a flat response around 1.0 from 3.6 s down to 2 ms. A response close to 1.0 is achieved for dose rates from 0.07 Sv/h to 35 Sv/h for both pixel sizes. Above this dose rate, the large pixels (220 µm edge length) are below the lower limit. The small pixels (55 µm edge length) stay within limits up to 704 Sv/h. The count rate linearity is compared to previous results, confirming the saturating count rate for high dose rates.

Dose estimation in X-ray backscatter imaging with Timepix3 and TLD detectors

“…Therefore, a lower uncertainty in the determination of the incoming X-ray spectrum can be achieved. This detector type has demonstrated effectiveness under high dose rates [10] and could be employed to characterize the dose produced by the backscattering scanner and verify this study's findings. A similar comparison as the one proposed has been done in [11], but without direct dose measurement with the Timepix3 and in a mixed radiation field.…”

“…This has led to the development of primary dosimeters based on ionization chambers [7]. On the other hand, active dosimeters based on hybrid pixel detectors, such as the Dosepix [8], show promising results to be used for personal dosimetry in continuous, pulsed, and mixed radiation fields [9][10][11].…”