Speaker
Description
High-power laser facilities generate ultra-short (sub-nanosecond), ultra-high dose-rate particle fields with instantaneous dose rates reaching $10^8 - 10^{10}$ Gy/s and complex mixed particle compositions including neutrons, photons, electrons, and protons. Accurate dosimetry under these conditions remains a major challenge due to detector saturation, recombination effects, limited temporal resolution, and strong pulse interference.
The EMPANADE (ElectroMagnetic Photon And Neutron Active DEtectors) project addresses these challenges through the development, benchmarking, and optimization of active radiation detectors for operation in extreme pulsed mixed fields. Commercially available systems, including BF$_3$ - and ³He-based neutron detectors, organic scintillators, and ionization chambers, will be systematically evaluated across three complementary environments: the PW laser facility at ELI Beamlines, FLASH radiotherapy conditions at Lausanne University Hospital (CHUV), and the SwissFEL and neutron irradiation facilities at the Paul Scherrer Institute (PSI). Detector responses will be compared against passive dosimeters and supported by Monte Carlo simulations to quantify performance limits, linearity, energy response, and temporal behavior. Based on these results, firmware, readout electronics, and measurement protocols will be refined to improve resilience, dynamic range, and reliability in nanosecond-scale pulsed radiation fields.
The EMPANADE project is part of the newly formed international collaboration, SWISSELITE. This contribution will present its experimental validation and Monte Carlo benchmarking strategies, detector optimization approaches, and first results toward robust dosimetry solutions for ultra-high dose-rate and mixed-field environments relevant to advanced accelerator research and FLASH applications.