Hostname: page-component-cd9895bd7-gvvz8 Total loading time: 0 Render date: 2024-12-26T04:45:51.767Z Has data issue: false hasContentIssue false
  • English
  • Français

Looking for the FIP Effect in EUV Spectra: Examining the Solar Case

Published online by Cambridge University Press:  12 April 2016

Bernhard Haisch ,
Julia L. R. Saba  and
Jean-Paul Meyer
Bernhard Haisch
Affiliation:
Lockheed Solar and Astrophysics Laboratory, Dept. 91-30, Bldg. 252, 3251 Hanover St., Palo Alto, CA 94304, USA
Julia L. R. Saba
Affiliation:
Lockheed Solar and Astrophysics Laboratory, Dept. 91-30, Bldg. 252, 3251 Hanover St., Palo Alto, CA 94304, USA stationed at Solar Data Analysis Center, Code 682.2, NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
Jean-Paul Meyer
Affiliation:
Service dAstrophysique, CEA/DSM/DAPNIA, Centre d’Etudes de Saclay, 91191 Gif-sur-Yvette, France

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Systematic differences between elemental abundances in the corona and in the photosphere have been found in the Sun. The abundance anomalies are correlated with the first ionization potentials (FIP) of the elements. The overall pattern is that low-FIP elements are preferentially enhanced relative to high-FIP elements by about a factor of four; the transition occurs at about 10 eV. This phenomenon has been measured in the solar wind and solar energetic particle composition, and in EUV and X-ray spectra of the corona and flares. The FIP effect should eventually offer valuable clues into the process of heating, ionization and injection of material into coronal and flaring loops for the Sun and other stars. The situation for the Sun is remarkably complex: substantial abundance differences occur between different types of coronal structures, and variations occur over time in the same region and from flare to flare. Anomalies such as enhanced Ne/O ratios, distinctly at odds with the basic FIP pattern, have been reported for some flares. Are the high-FIP elements underabundant or the low-FIP elements overabundant with respect to hydrogen? This issue, which has a significant impact in physical interpretation of coronal spectra, is still a subject of controversy and an area of vigorous research.

Type
XII. The Solar/Stellar Connection in the EUV
Information
International Astronomical Union Colloquium , Volume 152: Astrophysics in the Extreme Ultraviolet , 1996 , pp. 511 - 518
Copyright
Copyright © Kluwer 1996

References

Anders, E. & Grevesse, N. 1989, Abundances of the Elements: Meteoritic and Solar, Geochim. Cosmochi. Acta, 53, 197 Google Scholar
Athay, R.G. 1994, Separation of Low First Ionization Potential Ions From High First Ioniza-tion Potential Neutrals in the Low Chromosphere, ApJ, 423, 516 Google Scholar
Brickhouse, N.S. 1995, Dissecting the EUV Spectrum of Capella, these proceedingsGoogle Scholar
Cassé, M. & Goret, P. 1978, Ionization models of cosmic ray sources, ApJ, 221, 703 Google Scholar
Drake, J.J., Laming, J.M., & Widing, K.G. 1995a, Stellar Coronal Abundances. II. The First Ionization Potential Effect and Its Absence in the Corona of Procyon, ApJ, 443, 393 Google Scholar
Drake, J.J., Laming, J.M., & Widing, K.G. 1996, The FIP Effect and Element Abundance Anomalies in Late-Type Stellar Coronae, these proceedingsCrossRefGoogle Scholar
Drake, J.J., Laming, J.M., Widing, K.G., Schmitt, J.H.M.M., Haisch, B.M., & Bowyer, S. 1995, The Elemental Composition of the Corona of Procyon: Evidence for the Absence of the FIP Effect, Science, 2677, 1470 Google Scholar
Feldman, U. 1992, Highly Ionized Atoms in Space; or Highly Ionized Atoms, What Are They Teaching Us About the Solar Coronal Heating Problem? Physica Scripta, 46, 202 Google Scholar
Fludra, A. & Schmelz, J.T. 1995, Absolute Abundances of Flaring Coronal Plasma Derived from SMM Spectral Observations, ApJ, 447, 936 Google Scholar
Grevesse, N. & Noels, A. 1993, Cosmic Abundances of the Elements, in Origin and Evolution of the Elements, ed. Prantzos, N., Vangioni-Flam, E., &: Cassé, M., Cambridge Univ. Press, 15 Google Scholar
Haisch, B., Antones, A., & Schmitt, J.H.M.M. 1995, Solar-Like M-Class X-ray Flares on Proxima Centauri Observed by the ASCA Satellite, Science, 268, 1327 Google Scholar
Laming, J.M., Drake, J.J., & Widing, K.G. 1995, Stellar Coronal Abundances. III. The Solar First Ionization Potential Effect Determined from Full-Disk Observations, ApJ, 443, 416 Google Scholar
Malinovsky, M. & Heroux, L. 1973, An Analysis of The Solar Extreme-Ultraviolet Spectrum between 50 and 300 Å, ApJ, 181, 1009 Google Scholar
Mazur, J.E., Mason, G.M., Klecker, B., & McGumE, R.E. 1993, The Abundances of Hydrogen, Helium, Oxygen, and Iron Accelerated in Large Solar Events, ApJ, 404, 810 Google Scholar
Meyer, J.-P. 1985a, The Baseline Composition of Solar Energetic Particles, ApJS, 151 Google Scholar
Meyer, J.-P. 1985b, Solar-Stellar Outer Atmospheres and Energetic Particles, and Galactic Cosmic Rays, ApJS, 173 Google Scholar
Meyer, J.-P. 1993a, Element Fractionation at Work in the Solar Atmosphere, in: Origin and Evolution of the Elements, ed. Prantzos, N., Vangioni-Flam, E., & Cassé, M., Cambridge Univ. Press, 26 Google Scholar
Meyer, J.-P. 1993b, Elemental Abundances in Active Regions, Flares and the Interplanetary Medium, Adv. Space Res., 13(9), 377 Google Scholar
Mewe, R., Van Den Oord, G.H.J., Schrijver, C.J., & Kaastra, J.S. 1996, DEM Analysis with the Utrecht Plasma Code, these proceedingsGoogle Scholar
Philips, K.J.H., Pike, C.D., Lang, J., Watanabe, T., & Takahashi, M. 1994, Iron Kβ Line Emission in Solar Flares Observed by Yohkoh and the Solar Abundance of Iron, ApJ, 435, 888 Google Scholar
Phillips, K.J.H. et al. 1995, Evidence for the Equality of the Solar Photospheric and Coronal Abundance of Iron, Adv. Space Res., 15(7), 33 Google Scholar
Pottasch, S. 1964, On the Interpretation of the Solar Ultraviolet Emission Line Spectrum, Space Science Revs., 3, 816 Google Scholar
Reames, D.V. 1995, Coronal Abundances of O, Ne, Mg, and Fein Solar Active Regions, Adv. Space Res. 15(7), 41 Google Scholar
Saba, J.L.R. 1995, Spectroscopie Measurements of Element Abundances in the Solar Corona: Variations on the FIP Theme, Adv. Space Res., 15(7), 13 Google Scholar
Saba, J.L.R. & Strong, K.T. 1993, Coronal Abundances of O, Ne, Mg, and Fe in Solar Active Regions, Adv. Space Res. 13(9), 391 Google Scholar
Schmelz, J.T. 1993, Elemental Abundances of Flaring Solar Plasma: Enhances Neon and Sulfur, ApJ, 408, 373 Google Scholar
Schmitt, J.H.H.M., Haisch, B.M., & Drake, J.J. 1994, A Spectroscopie Measurement of the Coronal Density of Procyon, Science, 265, 1420 Google Scholar
Sheeley, N.R. 1995, A Volcanic Origin for the Material in the Solar Atmosphere, ApJ, 440, 884 Google Scholar
Strong, K.T., Lemen, J.R., & Linford, G.A. 1991, Abundance variations in solar active regions Adv. Space Res., 11, 151 Google Scholar
Sylwester, J., Lemen, J.R., & Mewe, R. 1984, Variation in observed coronal calcium abundance of X-ray flare plasmas Nature, 310, 665 Google Scholar
Veck, N.J., & Parkinson, J.H. 1981, Solar Abundances from X-ray Flare Observations, MNRAS, 197, 41 Google Scholar
Von Steiger, R., Wimmer Schweingruber, R.F., Geiss, J., & Gloeckler, G. 1995, Abundances Variations in the Solar Wind, Adv. Space Res. 15(7), 3 Google Scholar
Widing, K.G. & Feldman, U. 1989, Abundance Variations in the Outer Solar Atmosphere Observed with Skylab Spectroheliograms, ApJ, 344, 1046 Google Scholar
Widing, K.G. & Feldman, U. 1992, Element Abundances and Plasma Properties in a Coronal Polar Plume, ApJ, 392, 715 Google Scholar