Calculation of deuterium retention, re-emission and reflection from a tungsten material under D+ ions irradiation with ACAT-DIFFUSE code

We calculated, with a dynamic Monte Carlo code ACAT-DIFFUSE, fluxes of thermal D2 re-emission, reflection and segregated self-sputtering of D from a D+ implanted wrought tungsten material during a time sequence of l00 eV D+ implantation, post-implanted isothermal out-gassing and thermal desorption spectroscopy. The obtained result was in good agreement with an existing experiment if two different trap sites with de-trapping energy of 0.85 eV and 2.2 eV and density fraction of 0.05 D/W and 0.01 D/W were assumed to exist. The re-emission, reflection and self-sputtering fluxes in the implantation period were shown to be almost comparable. The integrated deuterium flux released in the same period was estimated. The amount of deuterium retained at 300 K was nearly six times higher than that at 473 K, which reflects the result that mobile atoms and atoms trapped in 0.85 eV trap existed abundantly at 300 K but scarcely at 473 K.