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 o f the Frank Laboratory for Neutron Physics is described. The facility is aimed at irradiation studies of various objects with area up to 800 cm(2) both at cryogenic and ambient temperatures. The energy spectra of neutrons are reconstructed by the method of threshold detector acti vation. The neutron fluence and gamma dose rates are measured by means of alanine and thermoluminescent dosimeters. The boron carbide and le ad filters or (n/gamma) converter provide beams of different ratio of doses induced by neutrons and photons. For the lead filter, the flux o f fast neutrons with energy more than 0.1 MeV is 1.4 x 10(10) n cm(-2) s(-1) and the neutron dose is about 96% of the total radiation dose. F or the (nir) converter, the gamma dose rate is similar to 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 succe ssfully at this Facility. (C) 1998 Elsevier Science B.V. All rights re served.