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 $H{}_{\mathrm{p}}(10)$ 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 3.7Sv/h shows a flat response around 1.0 from 3.6s down to 2ms. A response close to 1.0 is achieved for dose rates from 0.07Sv/h to 35Sv/h for both pixel sizes. Above this dose rate, the large pixels (220$\mu$m edge length) are below the lower limit. The small pixels (55$\mu$m edge length) stay within limits up to 704Sv/h. The count rate linearity is compared to previous results, confirming the saturating count rate for high dose rates.

6 pages, 4 figures. This work was accepted for publication in IEEE Transactions on Nuclear Science