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Solar coronal plasma composition is typically characterized by first ionization potential (FIP) bias. Using spectra obtained by Hinode's EUV Imaging Spectrometer (EIS) instrument, we present a series of large-scale, spatially resolved…

Solar and Stellar Astrophysics · Physics 2015-06-23 D. Baker , D. H. Brooks , P. Démoulin , S. L. Yardley , L. van Driel-Gesztelyi , D. M. Long , L. M. Green

The element abundances in the solar corona and solar wind are often different from those of the solar photosphere, typically with a relative enrichment of elements with low first ionization potential (FIP effect). Here we study the spatial…

Solar and Stellar Astrophysics · Physics 2023-02-22 Paola Testa , Juan Martinez-Sykora , Bart De Pontieu

The plasma composition of the solar corona is different from that of the solar photosphere. Elements that have a low first ionisation potential (FIP) are preferentially transported to the corona and, therefore, show enhanced abundances in…

The chemical composition of solar and stellar atmospheres differs from that of their photospheres. Abundances of elements with low first ionization potential (FIP) are enhanced in the corona relative to high FIP elements with respect to the…

The composition of the solar corona differs from that of the photosphere, with the plasma thought to fractionate in the solar chromosphere according to the First Ionisation Potential (FIP) of the different elements. This produces a FIP…

Within the coronae of stars, abundances of those elements with low first ionization potential (FIP) often differ from their photospheric values. The coronae of the Sun and solar-type stars mostly show enhancements of low- FIP elements (the…

Using spectra obtained by the EIS instrument onboard Hinode, we present a detailed spatially resolved abundance map of an active region (AR)-coronal hole (CH) complex that covers an area of 359 arcsec x 485 arcsec. The abundance map…

Solar and Stellar Astrophysics · Physics 2015-06-17 D. Baker , D. H. Brooks , P. Demoulin , L. van Driel-Gesztelyi , L. M. Green , K. Steed , J. Carlyle

Plasma composition in the solar atmosphere differs between the photosphere and corona, producing an observable difference in elemental abundance known as the FIP effect. The FIP effect is characterised by the ratio of low to high FIP…

Solar and Stellar Astrophysics · Physics 2026-03-06 Kristena D. Spruksta , David M. Long , Andy S. H. To

Elemental abundances in the solar corona are known to be different from those observed in the solar photosphere. The ratio of coronal to photospheric abundance shows a dependence on the first ionisation potential (FIP) of the element. We…

Solar and Stellar Astrophysics · Physics 2020-12-16 S. Narendranath , P. Sreekumar , Netra S Pillai , S. Panini , K. Sankarasubramanian , Juhani Huovelin

The different elemental abundances of the photosphere and the corona are striking features of not only the Sun, but other stars as well. This phenomenon is known as the FIP effect (FIP stands for first ionization potential), and its…

Solar and Stellar Astrophysics · Physics 2022-03-14 B. Seli , K. Oláh , L. Kriskovics , Zs. Kővári , K. Vida , L. G. Balázs , J. M. Laming , L. van Driel-Gesztelyi , D. Baker

The composition of plasma in the solar corona is characterised by the First Ionisation Potential (FIP) bias, and is thought to be the result of a ponderomotive force acting in the chromosphere to separate ionised from neutral plasma.…

Solar and Stellar Astrophysics · Physics 2026-03-06 Éabha Power , David M. Long , Teodora Mihailescu , Laura A. Hayes

Understanding elemental abundance variations in the solar corona provides an insight into how matter and energy flow from the chromosphere into the heliosphere. Observed variations depend on the first ionization potential (FIP) of the main…

Solar flares exhibit complex variations in elemental abundances compared to photospheric values. We examine the spatial and temporal evolution of coronal abundances in the X8.2 flare on 2017 September 10, aiming to interpret the often…

Sun-as-a-star coronal plasma composition, derived from full-Sun spectra, and the F10.7 radio flux (2.8 GHz) have been shown to be highly correlated (r = 0.88) during solar cycle 24. However, this correlation becomes nonlinear during…

Elemental abundance effects in active coronae have eluded our understanding for almost three decades, since the discovery of the First Ionization Potential (FIP) effect on the sun. The goal of this paper is to monitor the same coronal…

Solar and Stellar Astrophysics · Physics 2012-12-04 Raanan Nordon , Ehud Behar , Stephen A. Drake

It is well established that elemental abundances vary in the solar atmosphere and that this variation is organized by first ionization potential (FIP). Previous studies have shown that in the solar corona low-FIP elements, such as Fe, Si,…

Solar and Stellar Astrophysics · Physics 2016-06-22 Harry P. Warren , David H. Brooks , George A. Doschek , Uri Feldman

The First Ionization Potential (FIP) bias, whereby elemental abundances for low FIP elements in different coronal structures vary from their photospheric values and may also vary with time, has been widely studied. In order to study the…

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…

Solar and Stellar Astrophysics · Physics 2026-05-05 Paola Testa , Juan Martinez-Sykora , Bart De Pontieu , Alberto Sainz Dalda , David Long , Deborah Baker , David H. Brooks

We review our state of knowledge of coronal element abundance anomalies in the Sun and stars. We concentrate on the first ionization potential (FIP) effect observed in the solar corona and slow-speed wind, and in the coronae of solar-like…

Solar and Stellar Astrophysics · Physics 2015-09-30 J. Martin Laming

We analyse the coronal elemental abundances during a small flare using Hinode/EIS observations. Compared to the pre-flare elemental abundances, we observed a strong increase in coronal abundance of Ca XIV 193.84 {\AA}, an emission line with…

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