OBSERVATIONAL EVIDENCE OF BACK REACTION ON THE SOLAR SURFACE ASSOCIATED WITH CORONAL MAGNETIC RESTRUCTURING IN SOLAR ERUPTIONS

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.

[1]  Haimin Wang,et al.  CORONAL IMPLOSION AND PARTICLE ACCELERATION IN THE WAKE OF A FILAMENT ERUPTION , 2009, 0908.1137.

[2]  A. Donea,et al.  Magnetic field variations and seismicity of solar active regions , 2009, 0902.3856.

[3]  Haimin Wang,et al.  Changes of Magnetic Structure in Three Dimensions Associated with the X3.4 Flare of 2006 December 13 , 2008 .

[4]  Chang Liu,et al.  Successive Flaring during the 2005 September 13 Eruption , 2007 .

[5]  A Statistical Study of Rapid Sunspot Structure Change Associated with Flares , 2007 .

[6]  Haimin Wang.  Rapid Changes of Photospheric Magnetic Fields around Flaring Magnetic Neutral Lines , 2006 .

[7]  J. Harvey,et al.  Longitudinal Magnetic Field Changes Accompanying Solar Flares , 2005 .

[8]  Chang Liu,et al.  Reevaluation of the Magnetic Structure and Evolution Associated with the Bastille Day Flare on 2000 July 14 , 2005 .

[9]  Chang Liu,et al.  Rapid Penumbral Decay Associated with an X2.3 Flare in NOAA Active Region 9026 , 2005 .

[10]  Philip R. Goode,et al.  Rapid Change of δ Spot Structure Associated with Seven Major Flares , 2005 .

[11]  Haimin Wang,et al.  Evidence of Rapid Flux Emergence Associated with the M8.7 Flare on 2002 July 26 , 2004 .

[12]  Haimin Wang,et al.  Magnetic Field, Hα, and RHESSI Observations of the 2002 July 23 Gamma-Ray Flare , 2004 .

[13]  Rapid Penumbral Decay following Three X-Class Solar Flares , 2004 .

[14]  D. Gary,et al.  Flare-related Magnetic Anomaly with a Sign Reversal , 2003 .

[15]  Haimin Wang,et al.  Rapid Changes of Magnetic Fields Associated with Six X-Class Flares , 2002 .

[16]  Haimin Wang,et al.  Rapid Changes in the Longitudinal Magnetic Field Related to the 2001 April 2 X20 Flare , 2002 .

[17]  H. Hudson,et al.  Onset of the Magnetic Explosion in Solar Flares and Coronal Mass Ejections , 2001 .

[18]  Valentina V. Zharkova,et al.  Magnetic Energy Release and Transients in the Solar Flare of 2000 July 14 , 2001 .

[19]  Haimin Wang,et al.  Comparison of the 1998 April 29 M6.8 and 1998 November 5 M8.4 Flares , 2000 .

[20]  T. Sakurai,et al.  Magnetic field evolution leading to solar flares II. Cases with high magnetic shear and flare-related shear change , 2000 .

[21]  T. Sakurai,et al.  Magnetic Field Evolution Leading to Solar Flares I. Cases with Low Magnetic Shear and Flux Emergence , 2000 .

[22]  H. Hudson,et al.  Implosions in Coronal Transients , 2000, The Astrophysical journal.

[23]  Ian Sammis,et al.  Tangential Field Changes in the Great Flare of 1990 May 24 , 1999, The Astrophysical journal.

[24]  S. Antiochos,et al.  A Model for Solar Coronal Mass Ejections , 1998, astro-ph/9807220.

[25]  A. Kosovichev,et al.  X-ray flare sparks quake inside Sun , 1998, Nature.

[26]  D. Melrose.  A Solar Flare Model Based on Magnetic Reconnection between Current-carrying Loops , 1997 .

[27]  H. Zirin,et al.  Vector magnetic field changes associated with X-class flares , 1994 .

[28]  M. Hagyard,et al.  Evolutionary and flare-associated magnetic shear variations observed in a complex, flare-productive active region , 1993 .

[29]  H. Hudson,et al.  Rapid sunspot motion during a major solar flare , 1993 .

[30]  H. Zirin,et al.  Observations of vector magnetic fields in flaring active regions , 1993 .

[31]  Haimin Wang.  Evolution of vector magnetic fields and the August 27 1990 X-3 flare , 1992 .

[32]  H. Zirin,et al.  Transient magnetic field changes in flares , 1981 .

[33]  R. Kopp,et al.  Magnetic reconnection in the corona and the loop prominence phenomenon , 1976 .