TY - JOUR
T1 - Observational evidence of back reaction on the solar surface associated with coronal magnetic restructuring in solar eruptions
AU - Wang, Haimin
AU - Liu, Chang
N1 - Copyright:
Copyright 2015 Elsevier B.V., All rights reserved.
PY - 2010
Y1 - 2010
N2 - Most models of solar eruptions assume that coronal field lines are anchored in the dense photosphere and thus the photospheric magnetic fields would not have rapid, irreversible changes associated with eruptions resulted from the coronal magnetic reconnection. Motivated by the recent work of Hudson et al. on quantitatively evaluating the back reaction due to energy release from the coronal fields, in this Letter we synthesize our previous studies and present analysis of new events about flare-related changes of photospheric magnetic fields. For the 11 X-class flares where vector magnetograms are available, we always find an increase of transverse field at the polarity inversion line (PIL) although only four events had measurements with 1 minute temporal resolution. We also discuss 18 events with 1 minute cadence line-of-sight magnetogram observation, which all show prominent changes of magnetic flux contained in the flaring δ spot region. Except in one case, the observed limbward flux increases while diskward flux decreases rapidly and irreversibly after flares. This observational evidence provides support, either directly or indirectly, for the theory and prediction of Hudson et al. that the photospheric magnetic fields must respond to coronal field restructuring and turn to a more horizontal state near the PIL after eruptions.
AB - Most models of solar eruptions assume that coronal field lines are anchored in the dense photosphere and thus the photospheric magnetic fields would not have rapid, irreversible changes associated with eruptions resulted from the coronal magnetic reconnection. Motivated by the recent work of Hudson et al. on quantitatively evaluating the back reaction due to energy release from the coronal fields, in this Letter we synthesize our previous studies and present analysis of new events about flare-related changes of photospheric magnetic fields. For the 11 X-class flares where vector magnetograms are available, we always find an increase of transverse field at the polarity inversion line (PIL) although only four events had measurements with 1 minute temporal resolution. We also discuss 18 events with 1 minute cadence line-of-sight magnetogram observation, which all show prominent changes of magnetic flux contained in the flaring δ spot region. Except in one case, the observed limbward flux increases while diskward flux decreases rapidly and irreversibly after flares. This observational evidence provides support, either directly or indirectly, for the theory and prediction of Hudson et al. that the photospheric magnetic fields must respond to coronal field restructuring and turn to a more horizontal state near the PIL after eruptions.
KW - Sun: activity
KW - Sun: coronal mass ejections (CMEs)
KW - Sun: flares
KW - Sun: magnetic topology
KW - Sun: surface magnetism
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U2 - 10.1088/2041-8205/716/2/L195
DO - 10.1088/2041-8205/716/2/L195
M3 - Article
AN - SCOPUS:77956717018
VL - 716
SP - L195-L199
JO - Astrophysical Journal Letters
JF - Astrophysical Journal Letters
SN - 2041-8205
IS - 2 PART 2
ER -