Beam monitoring for electron FLASH beams.

Medina E., Abujami M., Bersani D., Cirio R., Data E., Galeone C., Giordanengo S., Mart`i Villareal O., Mas Milian F., Montalvan Olivares D., Monti V., Sacchi R., Vignati A.
  Martedì 13/09   09:00 - 13:30   Aula E - Rosalind Franklin   V - Biofisica e fisica medica   Presentazione
A tissue-sparing effect was demonstrated in ultra-high dose-rate irradiations (FLASH effect). Within the FRIDA project, the Turin University and INFN are characterizing the performance of thin silicon sensors and readout electronics for electron beam monitoring in ultra-high dose rates. TERA08, a chip based on the recycling integrator architecture, reads the signal of inversely polarized silicon sensors. The signal of one sensor strip is divided into the 64 chip channels and the current is obtained from summing all channels counts. The charge produced in silicon by FLASH electrons was simulated and initial tests were performed on a LINAC Elekta SL18, fully dedicated to research. Varying beam energies, distance from the beam, sensor position and dose rates (conventional range), the performance of the sensor is being evaluated. The reproducibility of the system and the possibility of studying the beam profile have been confirmed. Similar tests will be repeated after the LINAC upgrade (in the coming months) to produce high dose-rate electron beams. Different sensor geometries, alternative solid-state technologies and an upgraded version of the chip will be tested on FLASH beams.