Federico Keszti

Accurate dosimetry techniques are essential to the proper calibration of linacs. This is especially true in ultra-high dose rate radiotherapy, known colloquially as ‘FLASH’ radiotherapy, where beam delivery times are compressed to hundredths of a second. However, the ultra-high dose rates involved in FLASH pose a variety of problems for many state-of-the-art dosimeters. Most notably, ionization chambers, which are the most frequently used detector type in the clinical environment, suffer from complex dependencies in the ultra-high dose rate regime. Our group is developing a portable, millimetre-scale dosimeter, termed Aerrow, that is designed to bring the advantages and accuracy of absorbed dose calorimetry to the clinic. The performance of Aerrow is expected to improve, not be hindered, by radiation pulses with higher dose rates, as these produce higher signal-to-noise ratios in calorimeters. If validated, Aerrow would become the first clinically apt solution for accurate FLASH dosimetry. This is of fundamental importance; improved accuracy at the dosimetry stage means reliable and accurate treatment deliveries, which lead to better quality patient care.