Flexible Atomic Code APiP tutorial _ by Dr. Ming-Feng Gu

The Flexible Atomic Code (FAC) is a powerful, relativistic, and user-friendly tool for modeling atomic processes in plasmas. Its ability to handle a wide range of radiative and collisional processes, combined with its open-source availability and flexible interfaces, makes it invaluable for researchers in astrophysics, fusion, and plasma physics. Its applications span from diagnosing plasma conditions in lightning and fusion devices to modeling spectral emissions in astrophysical systems. While it excels for high-Z ions and single charge state calculations, users should be aware of its limitations for near-neutral ions and complex charge balance scenarios.

For further details, you can explore the FAC GitHub repository (https://github.com/flexible-atomic-code/fac) or refer to the draft papers included in the distribution.
https://amdis.iaea.org/meetings/apip21/
In this tutorial, we will discuss the practical usage of the Flexible Atomic Code (FAC) for intermediate users. Basic knowledge of atomic physics and plasma spectroscopy is assumed, but familiarity with FAC in particular is not required. The topics covered in the tutorial include: • Download and installation. • Atomic processes implemented in FAC. • SFAC and PFAC interfaces. • Handling FAC binary and ASCII output files. • Basic usage for simple atomic systems. • Coupling atomic calculations and collisional radiative modeling. • Advanced features: Many-body perturbation theory and R-Matrix. We will follow the tutorial through several practical examples, both simple and more advanced. Simple examples will demonstrate the use of FAC in obtaining limited sets of atomic parameters, such as energy levels, radiative rates, and collisional cross sections. More complex examples will demonstrate the use of the PFAC interface (via the Python scripting language) to generate large-scale datasets, and use them as input to collisional radiative models for spectroscopic modeling applications.