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Title: The Origin of Solar Filament Plasma Inferred from In Situ Observations of Elemental Abundances

Abstract

Solar filaments/prominences are one of the most common features in the corona, which may lead to energetic coronal mass ejections (CMEs) and flares when they erupt. Filaments are about 100 times cooler and denser than the coronal material, and physical understanding of their material origin remains controversial. Two types of scenarios have been proposed: one argues that the filament plasma is brought into the corona from photosphere or chromosphere through a siphon or evaporation/injection process, while the other suggests that the material condenses from the surrounding coronal plasma due to thermal instability. The elemental abundance analysis is a reasonable clue to constrain the models, as the siphon or evaporation/injection model would predict that the filament material abundances are close to the photospheric or chromospheric ones, while the condensation model should have coronal abundances. In this Letter, we analyze the elemental abundances of a magnetic cloud that contains the ejected filament material. The corresponding filament eruption occurred on 1998 April 29, accompanying an M6.8 class soft X-ray flare located at the heliographic coordinates S18E20 (NOAA 08210) and a fast halo CME with the linear velocity of 1374 km s{sup −1} near the Sun. We find that the abundance ratios of elementsmore » with low and high first ionization potential such as Fe/O, Mg/O, and Si/O are 0.150, 0.050, and 0.070, respectively, approaching their corresponding photospheric values 0.065, 0.081, and 0.066, which does not support the coronal origin of the filament plasma.« less

Authors:
; ;  [1];  [2];  [3]; ;  [4];  [5];  [6]
  1. Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment, and Institute of Space Sciences, Shandong University, Weihai, Shandong 264209 (China)
  2. Key Laboratory of Solar Activity, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 (China)
  3. Department of Climate and Space sciences and Engineering, University of Michigan, Ann Arbor, MI 48105 (United States)
  4. School of Earth and Space Sciences, Peking University, Beijing 100871 (China)
  5. School of Astronomy and Space Science, Nanjing University, Nanjing, Jiangsu 210093 (China)
  6. Department of Physics and Astronomy, George Mason University, Fairfax, VA 22030 (United States)
Publication Date:
OSTI Identifier:
22654542
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal Letters; Journal Volume: 836; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ABUNDANCE; CHROMOSPHERE; CLOUDS; EVAPORATION; FILAMENTS; HEAT EXCHANGERS; INJECTION; INSTABILITY; IONIZATION POTENTIAL; MASS; PHOTOSPHERE; PLASMA FILAMENT; SOFT X RADIATION; SOLAR FLARES; SUN; VELOCITY

Citation Formats

Song, H. Q., Chen, Y., Li, B., Li, L. P., Zhao, L., He, J. S., Duan, D., Cheng, X., and Zhang, J., E-mail: hqsong@sdu.edu.cn. The Origin of Solar Filament Plasma Inferred from In Situ Observations of Elemental Abundances. United States: N. p., 2017. Web. doi:10.3847/2041-8213/AA5D54.
Song, H. Q., Chen, Y., Li, B., Li, L. P., Zhao, L., He, J. S., Duan, D., Cheng, X., & Zhang, J., E-mail: hqsong@sdu.edu.cn. The Origin of Solar Filament Plasma Inferred from In Situ Observations of Elemental Abundances. United States. doi:10.3847/2041-8213/AA5D54.
Song, H. Q., Chen, Y., Li, B., Li, L. P., Zhao, L., He, J. S., Duan, D., Cheng, X., and Zhang, J., E-mail: hqsong@sdu.edu.cn. Fri . "The Origin of Solar Filament Plasma Inferred from In Situ Observations of Elemental Abundances". United States. doi:10.3847/2041-8213/AA5D54.
@article{osti_22654542,
title = {The Origin of Solar Filament Plasma Inferred from In Situ Observations of Elemental Abundances},
author = {Song, H. Q. and Chen, Y. and Li, B. and Li, L. P. and Zhao, L. and He, J. S. and Duan, D. and Cheng, X. and Zhang, J., E-mail: hqsong@sdu.edu.cn},
abstractNote = {Solar filaments/prominences are one of the most common features in the corona, which may lead to energetic coronal mass ejections (CMEs) and flares when they erupt. Filaments are about 100 times cooler and denser than the coronal material, and physical understanding of their material origin remains controversial. Two types of scenarios have been proposed: one argues that the filament plasma is brought into the corona from photosphere or chromosphere through a siphon or evaporation/injection process, while the other suggests that the material condenses from the surrounding coronal plasma due to thermal instability. The elemental abundance analysis is a reasonable clue to constrain the models, as the siphon or evaporation/injection model would predict that the filament material abundances are close to the photospheric or chromospheric ones, while the condensation model should have coronal abundances. In this Letter, we analyze the elemental abundances of a magnetic cloud that contains the ejected filament material. The corresponding filament eruption occurred on 1998 April 29, accompanying an M6.8 class soft X-ray flare located at the heliographic coordinates S18E20 (NOAA 08210) and a fast halo CME with the linear velocity of 1374 km s{sup −1} near the Sun. We find that the abundance ratios of elements with low and high first ionization potential such as Fe/O, Mg/O, and Si/O are 0.150, 0.050, and 0.070, respectively, approaching their corresponding photospheric values 0.065, 0.081, and 0.066, which does not support the coronal origin of the filament plasma.},
doi = {10.3847/2041-8213/AA5D54},
journal = {Astrophysical Journal Letters},
number = 1,
volume = 836,
place = {United States},
year = {Fri Feb 10 00:00:00 EST 2017},
month = {Fri Feb 10 00:00:00 EST 2017}
}
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