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Title: SOLAR MULTIPLE ERUPTIONS FROM A CONFINED MAGNETIC STRUCTURE

Abstract

How eruption can recur from a confined magnetic structure is discussed based on the Solar Dynamics Observatory observations of the NOAA active region 11444, which produced three eruptions within 1.5 hr on 2012 March 27. The active region (AR) had the positive-polarity magnetic fields in the center surrounded by the negative-polarity fields around. Since such a distribution of magnetic polarity tends to form a dome-like magnetic fan structure confined over the AR, the multiple eruptions were puzzling. Our investigation reveals that this event exhibits several properties distinct from other eruptions associated with magnetic fan structures: (i) a long filament encircling the AR was present before the eruptions; (ii) expansion of the open–closed boundary (OCB) of the field lines after each eruption was suggestive of the growing fan-dome structure, and (iii) the ribbons inside the closed magnetic polarity inversion line evolved in response to the expanding OCB. It thus appears that in spite of multiple eruptions the fan-dome structure remained undamaged, and the closing back field lines after each eruption rather reinforced the fan-dome structure. We argue that the multiple eruptions could occur in this AR in spite of its confined magnetic structure because the filament encircling the AR was adequatemore » for slipping through the magnetic separatrix to minimize the damage to its overlying fan-dome structure. The result of this study provides a new insight into the productivity of eruptions from a confined magnetic structure.« less

Authors:
;  [1]; ;  [2]
  1. Department of Physics and Astronomy, Seoul National University, Seoul 08826 (Korea, Republic of)
  2. Space Weather Research Laboratory, New Jersey Institute of Technology, Newark, NJ 07102 (United States)
Publication Date:
OSTI Identifier:
22654221
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal Letters; Journal Volume: 829; 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; DAMAGE; DISTRIBUTION; DOMED STRUCTURES; EXPANSION; FILAMENTS; MAGNETIC FIELDS; SUN

Citation Formats

Lee, Jeongwoo, Chae, Jongchul, Liu, Chang, and Jing, Ju. SOLAR MULTIPLE ERUPTIONS FROM A CONFINED MAGNETIC STRUCTURE. United States: N. p., 2016. Web. doi:10.3847/2041-8205/829/1/L1.
Lee, Jeongwoo, Chae, Jongchul, Liu, Chang, & Jing, Ju. SOLAR MULTIPLE ERUPTIONS FROM A CONFINED MAGNETIC STRUCTURE. United States. doi:10.3847/2041-8205/829/1/L1.
Lee, Jeongwoo, Chae, Jongchul, Liu, Chang, and Jing, Ju. 2016. "SOLAR MULTIPLE ERUPTIONS FROM A CONFINED MAGNETIC STRUCTURE". United States. doi:10.3847/2041-8205/829/1/L1.
@article{osti_22654221,
title = {SOLAR MULTIPLE ERUPTIONS FROM A CONFINED MAGNETIC STRUCTURE},
author = {Lee, Jeongwoo and Chae, Jongchul and Liu, Chang and Jing, Ju},
abstractNote = {How eruption can recur from a confined magnetic structure is discussed based on the Solar Dynamics Observatory observations of the NOAA active region 11444, which produced three eruptions within 1.5 hr on 2012 March 27. The active region (AR) had the positive-polarity magnetic fields in the center surrounded by the negative-polarity fields around. Since such a distribution of magnetic polarity tends to form a dome-like magnetic fan structure confined over the AR, the multiple eruptions were puzzling. Our investigation reveals that this event exhibits several properties distinct from other eruptions associated with magnetic fan structures: (i) a long filament encircling the AR was present before the eruptions; (ii) expansion of the open–closed boundary (OCB) of the field lines after each eruption was suggestive of the growing fan-dome structure, and (iii) the ribbons inside the closed magnetic polarity inversion line evolved in response to the expanding OCB. It thus appears that in spite of multiple eruptions the fan-dome structure remained undamaged, and the closing back field lines after each eruption rather reinforced the fan-dome structure. We argue that the multiple eruptions could occur in this AR in spite of its confined magnetic structure because the filament encircling the AR was adequate for slipping through the magnetic separatrix to minimize the damage to its overlying fan-dome structure. The result of this study provides a new insight into the productivity of eruptions from a confined magnetic structure.},
doi = {10.3847/2041-8205/829/1/L1},
journal = {Astrophysical Journal Letters},
number = 1,
volume = 829,
place = {United States},
year = 2016,
month = 9
}
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