TkN 2.0
Toolkit for Nuclei


Toolkit for Nuclei (TkN) is a C++ library providing an easy and fast access to a large variety of nuclear data measurements. It allows for example to access to ground state properties, level excited states energies and decay characteristics.

TkN can be used linked with ROOT, allowing to explore the TkN database interactively in the ROOT prompt terminal. It can also be compiled without any dependencies for lighter integration in simulation codes or theoretical nuclear models.

The source code is available on GitLab.

TkN Talks

License and references

The TkN project is governed by the CeCILL-B license under French law and abiding by the rules of distribution of free software. You can use, modify and/or redistribute the software under the terms of the CeCILL-B license as circulated by CEA, CNRS and INRIA at the following link

When citing TkN, please use the DOI specific to your TkN version available on Zenodo DOI.

All the references used by TkN (PubChem, X-RAY DATA BOOKLET, IAEA-NDS, NUDAT3, ENSDF, XUNDL) are detailled in the Data sources section.


  • A TkN users channel is available on the IN2P3's Rocket.Chat. To join it, please send a request by mail to the developer team
  • Join the mailing list to be informed on any release or updates regarding the TkN project: TkN mailing list

TkN developer team

Projects using TkN

Logo The Cubix spectra viewer

Cubix is a graphical interface dedicated to gamma-ray spectroscopy analysis. It provides a list of utilities for 1D-2D-3D gamma analysis (calibration, fits, background estimation, coincidences analysis...) and allows to interact with the TkN database to show the known transitions on a spectrum, or to find which nucleus can correspond to an observed transition coincidence.