| Zugriffsnummer | 55554 |
| Dokumenttyp | Konferenzartikel |
| Peer Review | mit Peer Review |
| Sprache | Englisch |
| Titel | Optimal geometric design of the diaphragm of a free-air ionization chamber for low-energy x-rays |
| Autor(in); Institution | |
| Quelle/Jahr | RAP 2025, Crete: Conference Proceedings:(2026), 16 - 20 |
| Schriftenreihe | RAP Conference Proceedings: 10 |
| Herausgeber(in) |
Jaksic, Aleksandar
|
| ISBN | 978-86-81652-01-5 |
| DOI | |
| URL | |
| Verlag | Nis: Sievert Association |
| Konferenzangaben | International Conference on Radiation Applications (RAP), Gournes, 26-30, May 2025, Greece |
| Freie Schlagworte | free-air ionization chamber ; primary standard ; air kerma ; diaphragm correction factor ; Monte Carlo simulation |
| Zusammenfassung | For reliable and comparable measurements of the dose quantity air kerma, dosimeter measurements must be traceable to a primary standard. Primary standard laboratories use free-air ionization chambers (FACs) for the primary realization of the unit of the air kerma free-in-air. Correction factors must be applied to convert measured charge to air kerma. One such correction factor is the correction factor for diaphragm effects (kdia). This study investigated the impact of the geometry of the diaphragm on kdia, as established FACs from different metrology institutes use different diaphragm geometries. The aim was to find the optimal diaphragm thickness and aperture shape to minimize the required diaphragm correction for the new PTB primary standard. Monte Carlo simulations were performed to determine kdia for various diaphragm geometries of a low-energy x-ray FAC. The influence of the diaphragm thickness and the aperture shape were investigated. The results showed that the diaphragm needs to be sufficiently thick to prevent transmission yet as thin as possible to reduce scattering at the inner surface of the aperture. The optimal diaphragm thickness, which depends on the air path length of the FAC, ranges from 0.8 mm to 1 mm. Using a diaphragm geometry with a more complex geometry than a simple 1 mm thick diaphragm with a cylindrical aperture is not advantageous. |
| Kostenfreier Zugang | Open Access Gold |
| Rechteinformation | CC BY 4.0 ; Creative Commons Attribution 4.0 License |
Zitierung
Gschweng, J. & Pojtinger, S. (2026). Optimal geometric design of the diaphragm of a free-air ionization chamber for low-energy x-rays. International Conference on Radiation Applications (RAP), Gournes, 26-30, May 2025, Greece. https://doi.org/10.37392/rapproc.2025.04