Deconvolution of neutron spectrum for a DT neutron generator based on a combination of activation method, unfolding processes and numerical simulations

•The method of neutron spectrum determination of the DT NG is described.•The Gravel and MAXED unfolding codes have been applied in our study.•The impact of different values of deconvolution parameters has been examined.•The impact of the default neutron spectrum shape on results has been checked.