Radiation damage to accelerator components of SPring-8 storage ring

Radiation damage to the accelerator components of the SPring-8 storage ring became serious after about four years of operation. Some rubber hoses were broken, resulting in water leakage, and some of the Synflex tubes, interlock cables, power cable covers, and so forth became damaged. Measurement of the radiation levels using GafChromic film and TLD showed that the maximum integrated radiation dose around the hoses at normal cell was 3.9×105Gy. The main radiation sources were the crotches and absorbers. Although there were two crotches and four absorbers in each of the 44 cells, two absorbers in particular caused serious radiation damage. Lead-plate shielding was installed around these absorbers to shield the nearby components.