MOSkin dosimetry for an ultra-high dose-rate, very high-energy electron irradiation environment at PEER

• Published in: Frontiers in physics Vol. 12
• Main Authors: Cayley, James, Tan, Yaw-Ren E., Petasecca, Marco, Cutajar, Dean, Breslin, Thomas, Rosenfeld, Anatoly, Lerch, Michael
• Format: Journal Article
• Language: English
• Published: Frontiers Media S.A 2024
• Subjects: Clinical Medicine; dosimetry; FLASH; Klinisk medicin; Medical and Health Sciences; Medicin och hälsovetenskap; MOSkin; Radiologi och bildbehandling; Radiology and Medical Imaging; Radiology, Nuclear Medicine and Medical Imaging; skin dose; ultra-high dose-rate; very high-energy electrons; VHEE
• ISSN: 2296-424X; 2296-424X
• DOI: 10.3389/fphy.2024.1401834

FLASH radiotherapy, which refers to the delivery of radiation at ultra-high dose-rates (UHDRs), has been demonstrated with various forms of radiation and is the subject of intense research and development recently, including the use of very high-energy electrons (VHEEs) to treat deep-seated tumors. Delivering FLASH radiotherapy in a clinical setting is expected to place high demands on real-time quality assurance and dosimetry systems. Furthermore, very high-energy electron research currently requires the transformation of existing non-medical accelerators into radiotherapy research environments. Accurate dosimetry is crucial for any such transformation. In this article, we assess the response of the MOS kin , developed by the Center for Medical Radiation Physics, which is designed for on-patient, real-time skin dose measurements during radiotherapy, and whether it exhibits dose-rate independence when exposed to 100 MeV electron beams at the Pulsed Energetic Electrons for Research (PEER) end-station. PEER utilizes the electron beam from a 100 MeV linear accelerator when it is not used as the injector for the ANSTO Australian Synchrotron. With the estimated pulse dose-rates ranging from ( 7.84 ± 0.21 ) × 1 0 5 Gy/s to ( 1.28 ± 0.03 ) × 1 0 7 Gy/s and an estimated peak bunch dose-rate of ( 2.55 ± 0.06 ) × 1 0 8 Gy/s, MOS kin measurements were verified against a scintillating screen to confirm that the MOS kin responds proportionally to the charge delivered and, therefore, exhibits dose-rate independence in this irradiation environment.