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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…

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…

We investigate in more detail the origin of chromospheric Alfven waves that give rise to the separation of ions and neutrals, the First Ionization Potential Effect (FIP), through the action of the ponderomotive force. In open field regions,…

Solar and Stellar Astrophysics · Physics 2017-08-09 J. Martin Laming

The relative abundances of chemical elements and isotopes have been our most effective tool in identifying and understanding energetic particles. The early surprise in solar energetic particles (SEPs) was 1000-fold enhancements in 3He/4He…

Solar and Stellar Astrophysics · Physics 2018-04-03 Donald V. Reames

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…

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

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

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 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…

In \citet{Stangalini20} and \citet{Deb20}, magnetic oscillations were detected in the chromosphere of a large sunspot and found to be linked to the coronal locations where a First Ionization Potential (FIP) effect was observed. In an…

Since the advent of X-ray and EUV spectroscopy, the discovery of the First Ionization Potential (FIP) effect--where coronal elemental compositions diverge from their photospheric values based on the element's FIP--has remained a key puzzle…

Solar and Stellar Astrophysics · Physics 2025-10-03 Biswajit Mondal , Amy R. Winebarger

We present evidences that anomalies in abundance of the chemical minor elements with the low first ionization potential (FIP) in the low corona of the late-type stars can be related with topology of the large-scale magnetic field. The solar…

Solar and Stellar Astrophysics · Physics 2018-05-09 V. V. Pipin , V. M. Tomozov

The ponderomotive force is suggested to be the main mechanism to produce the so-called first ionization potential (FIP) effect - the enrichment of low FIP elements observed in the outer solar atmosphere. It is well known that the ionization…

Solar and Stellar Astrophysics · Physics 2023-06-14 Juan Martínez-Sykora , Bart De Pontieu , Viggo H. Hansteen , Paola Testa , Q. M. Wargnier , Mikolaj Szydlarski

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 origin of the slow solar wind is not well understood, unlike the fast solar wind which originates from coronal holes. In-situ elemental abundances of the slow solar wind suggest that it originates from initially closed field lines that…

Solar and Stellar Astrophysics · Physics 2025-02-28 Alexandros Koukras , Daniel W. Savin , Michael Hahn

Accurate forecasting of space weather requires knowledge of the source regions where solar energetic particles (SEP) and eruptive events originate. Recent work has linked several major SEP events in 2014, January, to specific features in…

Solar and Stellar Astrophysics · Physics 2021-09-24 David H. Brooks , Stephanie L. Yardley

We present an analysis of the first connection mosaic made by the SPICE instrument on board of the ESA / NASA Solar Orbiter mission on March 2nd, 2022. The data will be used to map coronal composition that will be compared with in-situ…

The power spectrum of the evolving solar wind shows evidence of a spectral break between an inertial range of turbulent fluctuations at higher frequencies and a "$1/f$" like region at lower frequencies. In the ecliptic plane at $\sim 1$ AU,…

Solar and Stellar Astrophysics · Physics 2009-09-24 R. M. Nicol , S. C. Chapman , R. O. Dendy

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

Analysis of the Interball-1 spacecraft data (1995-2000) has shown that the solar wind ion flux sometimes increases or decreases abruptly by more than 20% over a time period of several seconds or minutes. Typically, the amplitude of such…

Space Physics · Physics 2011-02-08 Olga Khabarova , Georgy Zastenker