Validation of DT source term modelling in MCNP and MCUNED codes against SINBAD fusion benchmarks

•Three different MCNP modelling of the D–T neutron source, i.e. the standard MCNP source subroutine, the MCUNED code and the SDEF cards were used and validated on 3 FNG benchmark experiments available in the SINBAD database (FNG-SiC, FNG-HCPB and FNG-Cu). All three methods were found to provide consistent results, within 1–2-sigma of the MCNP M/C statistical uncertainty, for on- and off-axes measurements.•New inputs will be available in the SINBAD database and are expected to facilitate the use of these benchmarks for many MCNP users who do not have access to its source code. This revision will ultimately be extended to altogether 18 SINBAD benchmarks that presently include MCNP inputs with the DT neutron source subroutine.•It is expected that these results may prove useful for similar analyses performed using other than the MCNP code, such as for example TRIPOLI and SERPENT.