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arXiv · 2106.06714

Personal Dosimetry in Direct Pulsed Photon Fields with the Dosepix Detector

Dennis Haag·Sebastian Schmidt·Patrick Hufschmidt·Gisela Anton·Rafael Ballabriga·Rolf Behrens·Michael Campbell·Franziska Eberle·Christian Fuhg·Oliver Hupe·Xavier Llopart·Jürgen Roth·Lukas Tlustos·Winnie Wong·Hayo Zutz·Thilo Michel
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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 3.7$\,$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$\,\mu$m edge length) are below the lower limit. The small pixels (55$\,\mu$m 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.

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Dennis Haag, Sebastian Schmidt, Patrick Hufschmidt, Gisela Anton, Rafael Ballabriga, Rolf Behrens, Michael Campbell, Franziska Eberle, Christian Fuhg, Oliver Hupe, Xavier Llopart, Jürgen Roth, Lukas Tlustos, Winnie Wong, Hayo Zutz, Thilo Michel. 2021-06-12. Personal Dosimetry in Direct Pulsed Photon Fields with the Dosepix Detector. https://doi.org/10.1109/tns.2022.3222544

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