Demonstration of ultra-high dose rate electron irradiation at FLASH@PITZ.

The photo injector test facility at DESY in Zeuthen (PITZ) is building up an R&D platform, known as FLASH@PITZ, for systematically studying the FLASH effect in cancer treatment with its high-brightness electron beams, which can provide a uniquely large dose parameter range for radiation experiments. In this paper, we demonstrate the capabilities by experiments with a reduced parameter range on a startup beamline and study the potential performance of the full beamline by simulations.To measure the dose, Gafchromic films are installed both in front of and after the samples; Monte Carlo simulations are conducted to predict the dose distribution during beam preparation and help understand the dose distribution inside the sample.