Alejandro SonzogniNSDD 2007 Decay Data Library In ENDF/B-VII Alejandro Sonzogni National Nuclear Data Center Brookhaven National Laboratory Brookhaven Science Associates

Alejandro SonzogniNSDD ENDF/B-VII.0 Decay Data Sub-library  Single file, divided in datasets  All numerical, ready to be used in complex decay networks (reactors, stars) where nuclear decay and energy release is calculated as function of time.  A single dataset per ground state / isomer including all possible decays. Total of 3838 datasets in new sub- library. Previous version had 979 datasets (ENSDF 1985) mainly by Charlie Reich.  Work started in 2004 and was finished in December  Mostly derived from ENSDF, 2005 Nuclear Wallet Cards, with additional data. Dataset contents:  Energy level, isomer count (0 for GS, 1 for first isomer,…)  Branching ratios to daughter nuclide/s isomer counts  Half-life, spin and parity, mass  Average radiation energies  Discreet radiation energies and intensities In the ENSDF to ENDF translation:  Sometimes we need to add ENSDF datasets, ex 112In, EC=56% and B- =44%  Sometimes we need to subtract, ex 137Cs – 137Ba, 661  belongs to 137BA IT decay  Translate all strings to numbers.

Alejandro SonzogniNSDD T 1/2, %  -n from Pfeiffer, Kratz, Moller (2002) 1 ms to 1 s Partial T 1/2 information No Decay information other than Q-value Use of new Internal Conversion Coefficients (BRICC) Better from SPEBETA for 2 nd forbidden non-unique transitions 44 days < T 1/2 < 1x10 7 years TAGS (Total Absorption Gamma Spectrometer) 10 s 4 MeV Incomplete Decay Scheme and from integral measurement 48 materials from INEL + 2 ISOLDE/Jyvaskyla Subject of WPEC Subgroup 25 ENDF/B-VII.0 Decay Data Sub-library

Alejandro SonzogniNSDD ENDF/B-VII.0 Decay Data Sub-library Authorship information is carried throughout the sub-library

Alejandro SonzogniNSDD Decay Heat Decay Heat(t)=  i N i (t) E i E i : Energy released in decay, sum over all nuclear species involved in the decay, 732 fission products for a total of 1000 including the daughters

Alejandro SonzogniNSDD Delayed Neutrons d (thermal)=0.0159/fission (using ENDF/B-VII.0 decay data library and JEFF-3.1 fission yields) Very close to Keepin and JEFF-3.1 time dependence ENDF/B-VII.0: d (thermal)= /fission

Alejandro SonzogniNSDD Delayed Neutrons

Alejandro SonzogniNSDD Summary  New decay library as part of ENDF/B-VII.0  Much larger coverage, many more precise values of half-life, energy and intensity. Derived from the latest ENSDF files.  Inclusion of TAGS data and better treatment of long-lived beta emitters.  Validated with Decay Heat and Delayed Neutron calculations.  Sensitivity study to obtain list of priority nuclides, feedback to experimenters.