Joint Evaluated Fission and Fusion (JEFF) Library version 4.0 test 5
JEFF-4T5 brings significant updates, particularly to Major Actinides, Fission Products and Fission Yields. This release is an important milestone on the path to JEFF-4.0.
Superseded test library
Please note that this is a superseded test library that has not been approved for formal release and has been replaced by the JEFF-4.0 official library version.
For a comprehensive overview of the changes introduced in JEFF-4T5, we invite you to refer to this spreadsheet: JEFF-4 Evolution. It provides detailed insights into the modifications made.
Fission Yields (FY)
JEFF-4T5 includes new evaluations of the U-233 and Pu-241 thermal neutron-induced fission yields. U-235 and Pu-239 evaluations are also included, continuing the work done in previous test versions.
Each evaluation contains 5 files:
- the cumulative FY evaluation in the ENDF6 format.
- the independent FY evaluation in the ENDF6 format.
- the cumulative FY correlation matrix.
- the independent FY correlation matrix.
- a file describing how to read and use the correlation matrices.
| Release | Format | Content | # files | Download |
|---|---|---|---|---|
| JEFF-4T5 | ENDF6 | Thermal fission of U-233 | 5 | Download |
| JEFF-4T5 | ENDF6 | Thermal fission of U-235 | 5 | Download |
| JEFF-4T5 | ENDF6 | Thermal fission of Pu-239 | 5 | Download |
| JEFF-4T5 | ENDF6 | Thermal fission of Pu-241 | 5 | Download |
Thermal Scattering Law (TSL)
JEFF-4T5 takes TSL from JEFF-4T4, with the addition of:
- ThO2.
- Zy4 (Zircaloy).
And minor corrections for:
- Zr and H in ZrH_1.5 (Zirconium Hydride).
- Zr and H in ZrH_2 (Zirconium Hydride).
| Release | Format | Content | # files | Download |
|---|---|---|---|---|
| JEFF-4T5 | ENDF6 | Thermal Scattering Law Evaluations (download all) | 36 | Download |
| JEFF-4T5 | ENDF6 | Thermal Scattering Law Evaluations (choose and download) | 36 | Link |
Proton-induced activation data
JEFF-4T5 library for incident protons contains evaluations for 287 naturally abundant nuclides, originated from TENDL-2023, JENDL-5 and ENDF/B-VIII.1 libraries.
| Release | Format | Content | # files | Download |
|---|---|---|---|---|
| JEFF-4T5 | ENDF6 | Proton-induced activation data (information) | 288 | Link |
| JEFF-4T5 | ENDF6 | Proton-induced activation data (download all) | 288 | Download |
| JEFF-4T5 | ACE | Proton-induced activation data (information) | 288 | Link |
| JEFF-4T5 | ACE | Proton-induced activation data (download all) | 288 | Download |
Decay data
JEFF-4T5 sublibrary for decay data includes JEFF-3.3 data with new TAGS data for 8 radionuclides (Rb-93, Y-96, Y-96m, Y-99, Tc-103, Tc-108, I-138, and Cs-142). The Q-value has been updated in Tc-99 evaluation as well as EC/B- branching and decay radiation for Am-242.
| Release | Format | Content | # files | Download |
|---|---|---|---|---|
| JEFF-4T5 | ENDF6 | Radioactive decay data | 1 | Download |
| JEFF-4T5 | - | Radioactive decay data: checking codes verification | 1 | Download |
Neutron induced cross section evaluations
Major changes compared to JEFF-4T4:
- All TENDL files have been replaced with the latest TENDL-2025 data, released in February 2025.
- Al-27 was taken from JEFF-4T3 after benchmarking JEFF-4T4.
- Updates to the Major Actinides have been implemented.
- Covariances restored for F-19, Cr-50, Cr-52, Cr-53, Cr-54, Cu-63, Cu-65.
- Pm-147 and Pm-148m have been corrected due to inconsistent level ordering in isomeric production.
- Ta-181 has been adopted from ENDF/B-IX-beta.
- Minor corrections were made on many files.
For a comprehensive overview of the changes, please refer to the following spreadsheet: JEFF-4 Evolution.
| Release | Format | Code | Content | # files | Download |
|---|---|---|---|---|---|
| JEFF-4T5 | ENDF6 | - | Cross section evaluations (download all) | 593 | Download |
| JEFF-4T5 | ENDF6 | - | Cross section evaluations (choose and download) | 593 | Link |
| JEFF-4T5 | ENDF6 | - | Cross section evaluations (download all) | 2855 | Download |
| JEFF-4T5 | ENDF6 | - | Cross section evaluations (choose and download) | 2855 | Link |