Large-scale samples irradiation facility at the IBR-2 reactor in Dubna

The irradiation facility at the beam line no. 3 of the IBR-2 reactor of the Frank Laboratory for Neutron Physics is described. The facility is aimed at irradiation studies of various objects with area up to 800 cm2 both at cryogenic and ambient temperatures. The energy spectra of neutrons are reconstructed by the method of threshold detector activation. The neutron fluence and γ dose rates are measured by means of alanine and thermoluminescent dosimeters. The boron carbide and lead filters or (nγ) converter provide beams of different ratio of doses induced by neutrons and photons. For the lead filter, the flux of fast neutrons with energy more than 0.1 MeV is 1.4 × 1010n cm−2s−1 and the neutron dose is about 96% of the total radiation dose. For the (nγ) converter, the γ dose rate is ∼ 500 Gy h−1 which is about 85% of the total dose. The radiation hardness tests of GaAs electronics and materials for the ATLAS detector to be put into operation at the Large Hadron Collider (LHC) have been performed successfully at this facility.