Intense linear accelerators for material studies

Problems of designing intensive linear accelerators capable of producing neutron fluxes with an intensity of up to 1014-1015 neutron/cm2xs for studying material properties under irradiation are considered. Basic indices of deuteron linear accelerators for the projects of intensive neutron generators in a number of US laboratories and the ITEF are given. In all the projects it has been considered expedient to employ an Alvarez-type accelerator with quadrupole focusing of the beam by a system of electromagnetic lenses. Lenses for drift tubes of a short-wave linear accelerator are developed in ITEF, at an aperture radius of 1 cm the obtained gradient constitutes 5.1 kGs/cm. In Los-Alamos the samples of lenses made of samarium-cobalt alloy with gradient of 7.4 kGs/cm at an aperture radius of 0.84 cm are fabricated. A conclusion has been drawn that employment of magnetohard quadrupoles in the main part allows a considerable improvement of design and electric parameters of a linear accelerator with an intense steady beam