IrOnIc: How to Consider Hundreds of Millions of Iron-Group Lines in NLTE Model-Atmosphere Calculations

TL;DR

IrOnIc introduces a parallelized, statistical method to efficiently incorporate hundreds of millions of iron-group spectral lines into NLTE stellar atmosphere models, enabling more accurate and feasible computations.

Contribution

The paper presents a novel parallelized statistical approach, IrOnIc, for handling vast iron-group line data in NLTE model atmospheres, improving computational efficiency.

Findings

Successfully reduces computation time for iron-group lines

Provides publicly accessible tools via the German Astrophysical Virtual Observatory

Enables more accurate NLTE modeling with extensive line data

Abstract

Iron-group elements have a very high number of atomic levels and an overwhelming number of spectral lines. No NLTE model-atmosphere code can cope with these in a classical way. A statistical approach was developed over the last decade to decrease the number of levels and lines to a manageable amount. The Iron Opacity and Interface (IrOnIc) calculates sampled cross-sections and model-atom files as input for model-atmosphere computations. IrOnIc is presently transferred into a parallelized code to reduce the calculation time to a reasonable value. It will be accessible by the public as a service of the German Astrophysical Virtual Observatory.