Thermoluminescence in LiF induced by monoenergetic, parallel beam, 13.8 and 81.0 meV diffracted neutrons. The intrinsic TL response per absorbed neutron

The thermolumiscent response of TLD 600 and TLD 700 to thermal neutrons has been measured by exposure to a monoenergetic, parallel beam, 13.8- and 81.0 meV neutrons from a Kandi II diffractometer. The integral TL response in TLD 600 for a neutron fluence of 10¹⁰ neutrons/cm² was, after correction for self shielding, equivalent to the integral TL from 1470±90 and 4020±480 R (⁶⁰Co) at E(n) = 81.0 and 13.8 meV, respectively. From these results one calculates that 10¹⁰ n/cm² from a Maxwellian neutron energy distribution at T = 293.6°K would give an integral TL equal to 2330±145 and 2630±315 R (⁶⁰Co). TLD 700 responds to a neutron fluence of 10¹⁰ 81.0 meV neutrons/cm² with an integral TL equal to that from 0.12±0.007 R (⁶⁰Co), which similarly implies that 10¹⁰ Maxwellian neutrons/ cm² at T = 293.6°K would give an integral TL signal equal to 0.19±0.011 R (⁶⁰Co). The experimental results are essentially free of flux depression effects due to neutron backscattering. Monte Carlo calculations were carried out in an attempt to correct previously published results for neutron self shielding. The neutron induced Kerma is 0.135±0.01 times as effective as the ⁶⁰Co induced Kerma in producing the TL in TLD 600. This ratio of efficiencies is discussed in the framework of the TL LiF dependence on linear energy transfer.