Technology Transfer Department

Application sectors

Problem to solve

The main needs that are intended to be satisfied with the provision of the service include the testing and qualification of electronic components and materials (including biological samples, cultural heritage, etc.) to investigate the possible effects of ionizing radiation for applications in a wide spectrum of sectors and to promote the development of innovative technologies and systems. This benefits national and international research institutes, universities and industries.

Description

The TECHEA (Technologies for Health) irradiation facility is based on a compact 3 MeV S-band electron linear accelerator and its radiofrequency (RF) system. The facility is able to deliver either electrons or X-rays exploiting bremsstrahlung process, through an electron-to-photon conversion target made of 400 µm thick tungsten and 1.6 mm thick copper layers to stop residual surviving electrons. Its source is shielded to absorb the primary photon beam component and the secondary scattered radiation. The beam is collimated by a modular 13-degree angular aperture lead conical collimator, followed by a further lead block located behind the nominal irradiation position (isocenter) to shield the X-rays traversing the target when operating in the X-ray modality. The samples are irradiated in air at the fixed source-isocenter distance of 60 cm with a maximum spot diameter of 14 cm. The dose delivered to the target during the irradiation is measured and monitored through ionization chambers. In electron mode, an AC current transformer and a Faraday collector are used as beam monitoring systems to correlate the extracted beam current at the linac output with the pulse current at the target position. Moreover, the nominal electron beam energy of 3 MeV can be reduced through active, or a combination of active and passive, energy reduction techniques based on both proper settings of the RF source (magnetron and modulator) and the use of aluminum degraders. In particular, the energy of the electron beam can be degraded down to 1 MeV, which is of particular interest for radiation hardness testing of solar cells.

Research group involved