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arXiv · 2605.01993

The connection between solar coronal abundances and the underlying lower atmospheric properties

Paola Testa·Juan Martinez-Sykora·Bart De Pontieu·Alberto Sainz Dalda·David Long·Deborah Baker·David H. Brooks
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Abstract

Elemental abundances in the solar corona and solar wind are often observed to differ from those in the solar photosphere, most commonly showing an enhancement of low first ionization-potential (FIP) elements (the FIP effect). The observational evidence of the connection between the chemical fractionation in the solar atmosphere with FIP suggests that the mechanisms responsible for this effect take place in the chromosphere, where low-FIP elements are mostly ionized, while high-FIP elements remain mostly neutral. We discuss the findings of recent observational studies that have investigated the possible footprint of coronal abundance anomalies in the lower atmosphere. We also discuss the limitations of current observations, and future perspectives on addressing this important open issue in solar physics.

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Paola Testa, Juan Martinez-Sykora, Bart De Pontieu, Alberto Sainz Dalda, David Long, Deborah Baker, David H. Brooks. 2026-05-03. The connection between solar coronal abundances and the underlying lower atmospheric properties. https://arxiv.org/abs/2605.01993

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