fluence to TNID dose calculator for neutrons, adapted from sr-niel website calculators
NOTE:
Experimentally determined Ed values:
Ga: 21.5 eV, As: 21.5 eV as reported in [Campesato et al. (2019)] from proton, electron and neutron irradiations of solar cells. In Triple Junction solar cells, in which the dominat damage mechanism is that one due to the GaAs middle junction, a commonly effective value of Ed was 24 eV [Campesato et al. (2018), Campesato et al. (2019)].
In: 43 eV, Ga: 21 eV, P: 21 eV as reported in [Campesato et al. (2018)] for In0.49Ga0.51P single junction solar cells irradiated with electrons and protons. In [Campesato et al. (2019)] with electron, proton and neutron irradiation, it was shown that a commonly effective value of Ed=38 eV can be employed in an equivalent way.
The spectral neutron fluence employed for Triga reactor is that experimentally measured in Casaccia.
In requiring neutron fluence to ASIF reactor, it should be remembered that the niel dose is directly proportional to the required integral fluence, which, in turn, is directly proportional to the irradiation time.
The present Neutron NIEL calculator is based on values obtained with the software NJOY 2021, developed by Los Alamos National Laboratory, and the ENDF/B.VIII.0 cross section library.
NIEL for compounds is determined by means of Bragg's additivity rule, i.e., the overall NIEL in units of MeV cm2/g is obtained as a weighted sum in which each material contributes proportionally to the fraction of its atomic weight.
Currently, the lower energy limit for Neutrons NIEL is 1e-4 eV. The higher energy limit is 20 MeV.
