Radiation damage studies on natural and synthetic rock salt

Radiation damage studies are being made on natural rock salt from various localities, including potential repository sites and on synthetic melt-grown crystals. Sufficient information will be obtained to compute the radiation damage in repository salt at any point as a function of time, temperature, canister temperature and radiation levels, strain in the rock, salt, backfill materials, and other parameters. Most of the completed measurements have been made with unique equipment at BNL for making optical and other measurements on samples before, during, and after irradiation with 1- to 3-MeV electrons. Samples are irradiated in temperature-controlled chambers containing an inert exchange gas. Radiation damages on natural rock salts and synthetic melt-grown crystals, characterized by determining the radiation-induced F-center, colloid, and V-region absorption, are described in detail