During the last years we have been measuring prompt-fission gamma-ray emission, motivated by OECD/NEA high-priority nuclear data requests for new values especially for gamma-ray multiplicities and mean photon energies, in particular for 235U and 239Pu. Both isotopes are considered the most important ones with respect to the modelling of innovative cores for fast Generation-IV reactors. Our experimental techniques are discussed and results are presented. These results are investigated in terms of a revised version of systematics for prompt fission gamma-ray spectra (PFGS) characteristics as function of both atomic and mass number of the compound system, which allows estimating average gamma-ray multiplicity, mean and total photon energy in cases, where target nuclei are not available or not accessible experimentally. While this previously was done for thermal-neutron induced and spontaneous fission, we show how PFGS characteristics may be predicted for fission induced also by fast neutrons, e.g. on 238U. The results from these calculations are compared to corresponding experimental and theoretical values. On-going and future projects will be presented as well.
