The first main task of PTB within the UHDpulse project was to establish reference UHPDR electron beam. In this aim, the PTB research accelerator has been optimised to generate two 20 MeV reference beams which have been characterised along with the development of a Monte Carlo beam model enabling a third beam set-up for a total dose per pulse range from 0.1 Gy to 16 Gy per pulse. The second...
We will present our efforts to calibrate the METAS ICTs and the CHUV ACCT for ultra high dose per pulse electron beams using the PTB current generator. We will also show the appilcation of such a devices in the establishment of the Fricke primary and secondary standards
It has been shown that FLASH radiotherapy can significantly spare healthy tissues whilst still being at least as effective in curing cancer as radiotherapy at conventional dose rates. These properties promise reduced post-treatment complications, whilst improving patient access to proton beam radiotherapy and reducing costs. However, accurate dosimetry at UHDR is extremely complicated. The...
The generation of charged particle beams to ultra-high pulse dose rates (UHPDR) have been proposed for use within future applications, although dosimetry of these beams has proven to be technically challenging. Calorimetry techniques provide an arguably ideal solution but their application is not trivial due to the quasi-instantaneous and inhomogeneous dose deposition patterns. A first of its...
Using the two reference UHPDR electron beams characterised at the PTB facility, it was possible to perform the characterisation of Alanine/ESR secondary standard dosimetry system and to conclude that no dose rate dependency of the response occurs in a dose per pulse range between 0.1 Gy to 6 Gy per pulse. The second secondary standard to be tested was commercially available ionisation...
This contribution contains a review and outlook on the work with diamond detectors, which was carried out in the framework of the UHDpulse project. Using the commercially available microDiamond detector and modifications, the critical parameters for linearity under ultra-high dose per pulse conditions were determined and optimized. The optimized detector - flashDiamond - was validated on four...
A review on the use of diamond-based detector for time-resolved measurements under UH-DR and UH-DPP beams will be presented. In particular, the microDiamond and the flashDiamond detectors were utilized for dose and instantaneous dose rate measurements in UH-DR scanned ion beams and UH-DPP electron beams. The developed dosimetric systems were found to be suitable tools for the acquisition of...
A detailed numerical simulation of the charge carrier transport inside a parallel plate ionization chamber (PPIC) was developed in UHDPulse. This methodology allows the study of the contributions of ion-ion, electron-ion, electric field perturbation, beam time structure and influence magnitudes to the recombination effect [1,2].
The simulation has been commissioned against an extensive...
The code of practice (TRS398 and TG51) for the determination of the absorbed dose to water recommend the use of the two-voltage method (TVM) for the calculation of the ion recombination correction factor, which is based on the early Boag theory and do not take into account the contribution of free electrons to the ionization chamber signal. Later, Boag and contemporaries developed three...
High dose-rate radiotherapy has been shown to increase the differential response between healthy and tumour tissue. Moreover, Very High Energy Electrons (VHEEs) provide more favourable dose distributions than conventional radiotherapy electron and photon beams. Plane-parallel ionisation chambers are the recommended secondary standard systems for clinical reference dosimetry of electrons,...
The Dresden platform for high dose rate radiobiology consists of the superconducting research electron linear accelerator ELBE, two research beam lines at the Dresden University Proton Therapy facility and the DRACO laser accelerator. Recent radiobiological FLASH experiments using zebrafish embryos performed in these facilities will be presented. A focus will be laid on instrumentation and...
In this talk I will present the many potential applications of SiC radiation detectors for demanding radiation environments and I will give an overview of the recent technological developments at Instituto de Microelectrónica de Barcelona (CNM-CSIC) in Spain. Finally I will show the results of the SiC diodes for FLASH dosimetry developed by CNM in the framework of the EMPIR-UHDPulse project.
We tested micro-diamonds (collaboration with the University of Roma tor Vergata) and ultra-thin ionization chambers (collaboration with the university of Santiago de Compostela), and investigated optically stimulated luminescence (OSL) sheets, point scintillators and a 2D scintillating dosimetry system (in collaboration with SCK-CEN and Agfa).
The ElectronFlash allows systematic...
The Photo Injector Test facility at DESY in Zeuthen (PITZ) can provide unique beam parameters regarding delivered dose and dose rate. With an average dose rate of up to 1E7 Gy/s and peak dose rates of up to 4E13 Gy/s, PITZ is fully capable of UHDR irradiation which should allow FLASH radiation therapy.
A completely new beamline exclusively for FLASH RT and biology experiments was built. One...
Stray radiation produced by ultra-high dose-rates (UHDR) electron and proton beams is characterized using a MiniPIX Timepix3 detector equipped with a silicon sensor and integrated readout electronics. The chip-sensor assembly and chipboard on water-equivalent backing were detached and immersed in the water phantom. The deposited energy, particle flux, dose rate, and linear energy transfer...
An overview of developments in Bonner sphere neutron spectrometry for neutron stray radiation field characterization in EMPIR project UHDpulse.
A detector system for the purpose of quality assurance in radiation therapy is being developed and test measurements are presented. It is based on a beryllium oxide probe coupled to an optical fiber. Radioluminescence in the material generates photons, whose number is proportional to the dose absorbed in the probe. The photons are detected by very sensitive time resolving single photon...
The large energy distributions characterizing protons accelerated through laser-driven mechanisms presents a problem for potential clinical applications requiring precise energy selection. A method of radiochromic film (RCF) spectroscopy of polyenergetic proton beams based on a deconvolution procedure is presented. This has been tested through irradiation of several RCF configurations with a...
