LITHIUM LACTATE AS AN ESR DOSIMETER

The feasibility of lithium lactate (Li-lactate: CH3CH(OH)COOLi) as an electron spin resonance (ESR) dosimeter material has been studied and compared with lactose and a conventional alanine dosimeter. The ESR sp ectra of Li-lactate and lactose with the spectroscopic splitting g-fac tors of 2.0029 +/- 0.0003 and 2.0043 +/- 0.0003 respectively show hype rfine splitting with an intensity ratio of 1:3:3:1 and hyperfine coupl ing constants (A/g beta) of 1.82 +/- 0.06 and 1.88 +/- 0.06 mT, respec tively. The radical formation efficiency (G-value), i.e. the number of free radicals per 100 eV for alanine, Li-lactate and lactose were 0.9 5, 1.0 and 3.0, respectively. The sensitivity of Li-lactate to gamma-r ays is 10 times higher than that of alanine and 0.3 of lactose. The si gnal stability of Li-lactate was greater than that of lactose. (C) 199 8 Elsevier Science Ltd. All rights reserved.