Meeting Report

The 4^th biennial meeting of the Code Centres Network, 29 – 31 July 2015, was held at IAEA Headquarters in Vienna, Austria. The Scientific Secretaries were Hyun-Kyung CHUNG and Bastiaan BRAAMS (Atomic and Molecular Data Unit, IAEA).

The mission of the IAEA Atomic and Molecular (AM) data unit (Unit) is to provide internationally recommended numerical databases on atomic, molecular and plasma-material interaction data (AM/PMI) for fusion applications. Unfortunately, it is extremely difficult to find even evaluated data, let alone recommended data. Since 2012 the Unit has collaborated with AM physicists to increase AM data evaluation and uncertainty quantification (UQ) activities in the field. In July 2014 the Unit organized a joint workshop at ITAMP (NSF-funded Institute of Theoretical Atomic, Molecular and Optical Physics, Harvard-Smithsonian Center for Astrophysics, Cambridge, MA, USA) to address the issues of Uncertainty Assessment for Theoretical AM Scattering Data and as a result, a technical document on Guidelines for Uncertainty Estimates for Theoretical AM Data was developed.

Our activities are in accordance with an increasing effort in the Engineering and Physical Sciences communities to establish mathematical and statistical foundations of verification, validation and uncertainty quantification of complex models and simulations; for example see a National Research Council (NRC) report on this topic. In June 2015 the Unit attended a BIPM Workshop on Measurement Uncertainty in order to address the UQ activities in the theoretical AM sciences.

In addition to AM data, the Unit wants to support UQ activities for theoretical PMI data. The present Technical Meeting (TM) of the International Code Centre Network (CCN) on Simulations of Plasma-Material Interaction Experiments will bring together experts involved in PMI data to discuss the current status and future directions of the UQ activities for theoretical PMI data. In order to make this meeting relevant to fusion the meeitng will focus on PMI related to hydrogen retention. The relevant topics will be uncertainties with interatomic potentials, DFT simulations, MD simulations, KMC simulations and Rate simulations for hydrogen retention and migration in fusion material. The meeting will proceed with presentations by participants on uncertainties associated with PMI data followed by discussion sessions on UQ methods and procedures.