Installation and application of an intense 7Li(p,n) neutron source for 20-90 MeV region.

An intense (7)Li(p,n) neutron source was installed with the K = 110-MeV azimuthally varying field (AVF) cyclotron at the Cyclotron and Radioisotope Center (CYRIC), Tohoku University, by employing a special arrangement to allow a short target-sample distance down to 1 m. The source can deliver a neutron flux around 1.5 x 10(6) n cm(-2) s(-1) with a lithium target of thickness equivalent to 2-MeV energy loss and 3-microA proton beam, which is the highest intensity in the world. The source is successfully used for (1) measurement of neutron cross sections relevant to radiation safety and radiation effect and (2) semiconductor irradiation test for single-event effect and (3) characterisation of neutron detectors and dosemeters.