nucdata.toolsabout

nucdata.tools is a web workbench for evaluated nuclear data.

Inspect evaluated nuclear data in the Viewer, generate reproducible NJOY-2016 processing decks, and keep provenance records that make the processing chain inspectable.

Open Viewer →Build NJOY deck

Core workflows

Viewer

open →

inspect and compare evaluated data

  • Overlay ENDF/B-VIII.1, JEFF-3.3, JENDL-5, and TENDL-2021
  • Switch isotope, MT reaction, temperature, library, and units
  • Deep-link every view for sharing and review

NJOY Generator

open →

build reproducible processing workflows

  • Generate NJOY-2016 decks from reactor-oriented presets
  • Form-driven, deterministic — no LLM in the deck path
  • Download runnable bundles with runner.sh, verifier scripts, provenance

What the Viewer shows

Cross sections

  • Same-axis overlays across ENDF/B-VIII.1, JEFF-3.3, JENDL-5, TENDL-2021
  • MT reactions with temperature-broadened curves at 294 / 600 / 900 / 1200 / 1800 K
  • EXFOR experimental overlays and shareable deep links

Secondary data

  • Angular distributions (MF=4 / 6)
  • Outgoing neutron spectra (MF=5 / 6)
  • Fission-yield preview and decay chains on a (Z, N) map

Uncertainty + reactor context

  • MF=33 diagonal covariance bands
  • Group-mesh overlays: WIMS, SHEM, ECCO, VITAMIN-J, SCALE / CSEWG-style meshes
  • Thermal values, resonance integrals, Maxwellian and spectrum-averaged cross sections
  • Material mixtures by formula or preset, with macroscopic Σ when density is provided

What the Generator builds

Processing stages

  • PENDF — pointwise + Doppler
  • GENDF — multigroup
  • DRAGR — DRAGON-format draglib
  • ACER — Monte-Carlo ACE
  • ERRORR — MF=33 multigroup covariance

Presets

  • LWR · WIMS-D 69
  • GEN-3 LWR · SHEM-281
  • SFR · SHEM-EPM 370
  • OpenMC CE (continuous-energy)
  • …

Bundles

  • Per-stage .in files
  • runner.sh per isotope + master runner_all.sh
  • Batch mode with bulk-edit toolbar
  • verify_outputs.py + per-slot verify_report.json
  • manifest.json + sha256 hashes

Trust and reproducibility

nucdata.tools records how processed libraries are produced: source evaluation, NJOY recipe, generated artifacts, manifest files, hashes, and verification reports.

A transport-benchmark validation layer is under active development, but it is not presented as a final pass/fail claim yet.

current validation notes →

Data and processing provenance

Data sources

  • ENDF/B-VIII.1 — BNL / NNDC (Oct 2024)
  • JEFF-3.3 — OECD-NEA Data Bank (Nov 2017)
  • JENDL-5 — JAEA Nuclear Data Center (Dec 2021)
  • TENDL-2021 — PSI / NRG Petten (Dec 2021)
  • EXFOR — IAEA-NDS experimental compilation
  • OpenMC depletion chain — preview decay / FPY data

Processing

  • NJOY-2016 (with DRAGR add-on) — LANL
  • openmc.data — OpenMC project
  • SANDY — ENEA, where applicable
  • Per-library manifests + sha256 hashes
  • verify_report.json on every produced library slot

Limitations

  • Interactive curves are downsampled; final integrals should use the original processed data.
  • The ENDF upload parser is limited (MF=1 / MF=3 focused).
  • Fission-yield data is a chain-derived preview, not the full ENDF MF=8 set.
  • Validation is under development — see current validation notes.

Contact

If a cross section looks suspicious, a deck breaks, or a resonance peak goes missing — bowen.cui@polymtl.ca.