Wonder 2026: 7th edition of the International Workshop On Nuclear Data Evaluation for Reactor Applications

Session

Decay Data and Delayed Neutrons

Jul 2, 2026, 8:45 AM

Conveners

Decay Data and Delayed Neutrons

• David Bernard (CEA/DES/IRESNE/DER/SPRC/LEPh)

70. Contribution of the DDEP collaboration to the JEFF4 Radioactive Decay Data library

Xavier Mougeot

7/2/26, 8:45 AM

73. Recent progress in experimental beta spectrometry at the LNE-LNHB

Sylvain Leblond (LNHB)

7/2/26, 9:10 AM

Precise knowledge of beta spectra is of primary importance for numerous applications, including radioactive waste management, decay heat calculations, internal vectorized radiotherapy, and radionuclide metrology, as well as for fundamental studies in nuclear structure and neutrino physics. However, accurate theoretical descriptions of beta spectra remain challenging, particularly for forbidden...

52. Bayesian Inference of Delayed Neutron Multigroup Constants: Application to 9 MeV 238U Photofission

Johann Piekar (CEA-LIST)

7/2/26, 9:30 AM

While delayed-neutron (DN) data from neutron-induced fission have been refined for decades, photofission DN data remain comparatively sparse. Current photofission evaluations rely on sequential peeling or non-negative least squares (NNLS), which cannot deliver the full parameter covariance matrices required by modern nuclear-data libraries.

We present a Markov Chain Monte Carlo (MCMC)...

61. Simulation of a monoenergetic neutron source with GEANT4

Mathieu Boissier (CEA/DES/IRESNE/DER/SPRC/LEPh)

7/2/26, 9:50 AM