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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 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 Solar First Ionization Potential (FIP) effect, where low-FIP elements are enriched in the corona relative to the photosphere, while high-FIP abundances remain unchanged, has been known for a long while. High resolution X-ray…

Astrophysics · Physics 2009-11-13 R. Nordon , E. Behar

We discuss the evolution of solar coronal element abundances over an active region lifetime. Magneto-convection drives the complexity of magnetic fields that emerge above the photosphere. This complexity is dissipated, together with that of…

Solar and Stellar Astrophysics · Physics 2025-12-16 David H. Brooks , Deborah Baker , David M. Long. Paola Testa , Harry P. Warren

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

Elemental abundances in solar flares are observed to vary both spatially and temporally, but the underlying mechanisms remain poorly understood. There is an interplay between advection and the preferential acceleration of low first…

The solar corona shows a distinctive pattern of elemental abundances that is different from that of the photosphere. Low first ionization potential (FIP) elements are enhanced by factors of several. A similar effect is seen in the…

Solar and Stellar Astrophysics · Physics 2018-08-29 David H. Brooks

We have used Chandra to resolve the nearby 70 Oph (K0 V+K5 V) and 36 Oph (K1 V+K1 V) binary systems for the first time in X-rays. The LETG/HRC-S spectra of all four of these stars are presented and compared with an archival LETG spectrum of…

Astrophysics · Physics 2009-11-11 Brian E. Wood , Jeffrey L. Linsky

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

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

The chemical composition of the solar corona is different from that of the solar photosphere, with the strongest variation being observed in active regions (ARs). Using data from the Extreme Ultraviolet (EUV) Imaging Spectrometer (EIS) on…

The abundances of low First Ionisation Potential (FIP) elements are three to four times higher (FIP bias) in the closed loop active corona than in the photosphere, known as the FIP effect. Observations suggest that the abundances vary in…

Solar and Stellar Astrophysics · Physics 2023-04-19 Lakshitha Nama , Biswajit Mondal , S Narendranath , KT Paul

Coronal elemental abundances are known to deviate from the photospheric values of their parent star, with the degree of deviation depending on the First Ionization Potential (FIP). This study focuses on the coronal composition of stars with…

Solar and Stellar Astrophysics · Physics 2015-05-13 Uria Peretz , Ehud Behar , Stephen A. Drake

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

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…

We examine the different element abundances exhibited by the closed loop solar corona and the slow speed solar wind. Both are subject to the First Ionization Potential (FIP) Effect, the enhancement in coronal abundance of elements with FIP…

We investigate the time evolution of relative elemental abundances in the context of the first ionization potential effect focusing on an active region. Our aim is to characterize this evolution in different types of solar active region…

Solar and Stellar Astrophysics · Physics 2026-02-11 T. Varesano , D. M. Hassler , N. Zambrana Prado , J. M. Laming , J. Plowman , D. J. Knipp , M. Molnar , K. Barczynski , The SPICE consortium

We revisit in more detail a model for element abundance fractionation in the solar chromosphere, that gives rise to the "FIP Effect" in the solar corona and wind. Elements with first ionization potential below about 10 eV, i.e. those that…

Solar and Stellar Astrophysics · Physics 2014-11-18 J. Martin Laming

The XMM-Newton Reflection Grating Spectrometer Team has obtained observations ofa large number of coronal sources of various activity levels, ages, and spectraltypes. In particular, X-ray bright RS CVn binary systems display saturated…

Astrophysics · Physics 2007-05-23 Marc Audard , Manuel Guedel

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
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