Time structures of proton pencil beam scanning delivery on a microsecond scale measured with a pixelated semiconductor detector Timepix3

The time structures of proton spot delivery in pencil beam scanning (PBS) proton therapy are critical for applications like 4D dose calculations and FLASH therapy. This study uses a pixelated semiconductor detector, AdvaPIX-Timepix3, with a temporal resolution of 1.56 ns, to directly measure proton delivery time structures for synchrotron and synchrocyclotron accelerators. Measurements captured key parameters such as energy layer switch time, magnet switch time, and spot switch time, with uncertainties below 1.5%. Results revealed near-continuous proton spill for synchrotron systems and high-intensity pulsed delivery for synchrocyclotrons. The findings demonstrate that the AdvaPIX-Timepix3 detector provides a precise, non-invasive alternative to log-file based methods for characterizing time structures of therapeutic proton beams.

Text supplied in this site's publication record. Consult the full paper for methods, experimental conditions and limitations.