ºÚÁÏÉçapp

Science

Release of IMAS infrastructure and physics models as open source

8 Dec 2025 - S. Pinches, O. Hoenen, A. Loarte and A. Becoulet, Science & Integration Department

In another step to support global efforts to develop fusion energy, the ºÚÁÏÉçapp is releasing the tools it uses for physics modelling and analysis—the ºÚÁÏÉçapp Integrated Modelling & Analysis Suite, IMAS—under open-source licenses. 

--Visualization with IMAS-ParaView () of induced currents in vacuum vessel and plasma electron temperature during disruption in ºÚÁÏÉçapp simulated with JOREK code ().

In line with the ongoing efforts* to facilitate the development of fusion energy in the Members, the ºÚÁÏÉçapp is pleased to announce that the Integrated Modeling and Analysis Suite (IMAS), including a wide range of physics modelling codes for tokamak plasma scenarios, is now available for access and use under open-source licenses on the . This culminates the effort initiated earlier this year after the decision by the ºÚÁÏÉçapp Director-General to release the IMAS Intellectual Property owned by the ºÚÁÏÉçapp as open source, and has only been possible thanks to the support from a wide range of institutions across the ºÚÁÏÉçapp Members.

The Integrated Modelling and Analysis Suite (IMAS) provides standard tools and applications to support the integrated modelling and data analysis of fusion plasmas and has been developed in close collaboration with the Members’ fusion communities. This development has been guided by the need to address plasma scenario and plasma diagnostic design/performance issues and to optimize the ºÚÁÏÉçapp Research Plan towards the achievement of ºÚÁÏÉçapp’s goals. The IMAS infrastructure software now released as open source allows users to manipulate and perform a wide range of operations on data that follows the . This is a device-agnostic standard for fusion data capable of describing experiments and simulations that has resulted from a decades-long effort by the ºÚÁÏÉçapp and the ºÚÁÏÉçapp Members. The support of EUROfusion and EURATOM to enable this open-source release is gratefully acknowledged.   

Waveform-Editor (https://github.com/iterorganization/Waveform-Editor) showing plasma shape calculated with NICE code (https://gitlab.inria.fr/blfauger/nice)

In addition to the infrastructure software, a wide range of physics models used extensively in the fusion modelling community have also been made openly available. This includes (for the modelling of edge plasmas, principally composed of and ), (a graphical interface for SOLPS-ºÚÁÏÉçapp), (for modelling tokamak scenarios) and a Heating & Current Drive Workflow (). The institutions that own the intellectual property for these codes (Max-Planck-Institut für Plasmaphysik, Forschungszentrum Jülich, Fusion for Energy, and the Plasma Simulation Center) are gratefully acknowledged for their support. Fully aligned with this ºÚÁÏÉçapp-led effort, many research institutes from the ºÚÁÏÉçapp Members and non-Members have also made their plasma simulation codes openly available under open-source licenses (such as , , , etc.), greatly enhancing the open access of plasma simulation codes to the wider fusion community, including privately funded initiatives.  

The IMAS software set available as open source will gradually be expanded moving forward and enriched with additional documentation to help users find the appropriate IMAS software for a given use-case. Near-term steps include the release of synthetic diagnostic models to simulate the expected measurements in tokamak plasma scenarios and support the inference of plasma properties.

And of course, contributions in all forms (source code improvements, bug reports, documentation, installation recipes on different platforms, etc.) by the worldwide fusion research community are very much welcome for all these different software packages.

See  

* The ºÚÁÏÉçapp Council, in its 33rd (November 2023) and 34th (June 2024) meetings, requested Members to encourage their national entities (government agencies, research institutes, private sector fusion companies) to support global fusion efforts.