Journal
ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES
Volume 262, Issue 2, Pages -Publisher
IOP Publishing Ltd
DOI: 10.3847/1538-4365/ac8977
Keywords
-
Categories
Funding
- NASA-APRA [80NSSC19K0679]
Ask authors/readers for more resources
This study reports the velocity-dependent calculations of n l-resolved charge exchange cross sections using the time-dependent lattice method. It investigates the influence of these cross sections on emission line ratios and compares them to the analytical distributions commonly used. The results suggest a consensus among n and n l-resolved data for atomic H targets, while no consensus is found for atomic He targets.
Charge exchange (CX) between highly charged ions and neutrals within the geocorona and heliosphere introduces a problematic background for every X-ray observation. For H-like ions the l states within each n shell are degenerate. The majority of CX spectral models rely on calculated n-resolved cross sections, and the distribution of l states is assumed to follow one of several analytical expressions. Laboratory data to validate these distributions at solar wind velocities is not available. Explicitly velocity-dependent calculations of n l-resolved CX cross sections using the time-dependent lattice (TDL) method for Ne10+ incident on atomic H and He at 1-5 keV amu(-1) are reported. The cross sections are incorporated into a radiative cascade model, and the influence of n- and n l-resolved cross sections on possibly diagnostic emission line ratios is investigated. Comparisons of the l distribution extracted from the TDL cross sections to the predominantly used analytical distributions reveals a consensus among n and n l-resolved data at solar wind velocities, suggesting a statistical distribution is most appropriate for CX collisions involving atomic H. No consensus is found for atomic He targets, and the l distribution extracted from n l-resolved cross sections appears most appropriate. Open questions related to CX are discussed with emphasis on experimental methods to resolve them. Spectral measurements at an electron beam ion trap facility are planned to benchmark the presented cross section data.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available