J/ApJ/885/49 Global energetics of solar flares. IX. (Aschwanden, 2019)
Global energetics of solar flares.
IX. Refined magnetic modeling.
Aschwanden M.J.
<Astrophys. J., 885, 49 (2019)>
=2019ApJ...885...49A 2019ApJ...885...49A
ADC_Keywords: Sun; Stars, flare; Magnetic fields; Ultraviolet
Keywords: Solar flares ; Magnetic fields
Abstract:
A more accurate analytical solution of the vertical-current
approximation nonlinear force-free field (VCA3-NLFFF) model is
presented that includes, besides the radial (Br) and azimuthal
(Bφ) magnetic field components, a poloidal component
(Bθ/=0) as well. This new analytical solution is of
second-order accuracy in the divergence-freeness condition and of
third-order accuracy in the force-freeness condition. We reanalyze the
sample of 173 GOES M- and X-class flares observed with the Atmospheric
Imaging Assembly and Helioseismic and Magnetic Imager on board the
Solar Dynamics Observatory (SDO). The new code reproduces helically
twisted loops with a low winding number below the kink instability
consistently, avoiding unstable, highly twisted structures of the
Gold-Hoyle flux rope type. The magnetic energies agree within
EVCA3/EW=0.99±0.21 with the Wiegelmann (W-NLFFF) code. The
time evolution of the magnetic field reveals multiple, intermittent
energy buildup and releases in most flares, contradicting both the
Rosner-Vaiana model (with gradual energy storage in the corona) and
the principle of timescale separation (τflare≪τstorage)
postulated in self-organized criticality models. The mean dissipated
flare energy is found to amount to 7%±3% of the potential energy,
or 60%±26% of the free energy, a result that can be used for
predicting flare magnitudes based on the potential field of active
regions.
Description:
We analyzed the same data set of 173 solar flares presented in PaperI,
which includes all M- and X-class flares observed with the Solar
Dynamics Observatory (SDO) during the first 3.5yr of the mission (2010
June 1 to 2014 January 31). We use the 45s line-of-sight magnetograms
from Helioseismic and Magnetic Imager (HMI/SDO) and make use of all
coronal Extreme Ultraviolet Variability (EUV) channels of Atmospheric
Imaging Assembly (AIA/SDO) (in the six wavelengths 94, 131, 171, 193,
211, 335Å), in the temperature range of T∼0.6-16MK. The spatial
resolution is ∼1.6" for AIA, and the pixel size of HMI is 0.5".
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 94 173 Energy parameters of the 174 M- and X-class flare
events in the longitude range of -45°,
+45°, computed with the new VCA3-NLFFF Code
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See also:
J/ApJ/747/L41 : Solar flares probabilities (Bloomfield+, 2012)
J/ApJ/757/94 : Solar flares observed with GOES and AIA (Aschwanden, 2012)
J/ApJ/797/50 : Global energetics of solar flares. I. (Aschwanden+, 2014)
J/A+A/574/A37 : Movies of 2012-10-16 solar flare (Dalmasse+, 2015)
J/ApJ/802/53 : Global energetics of solar flares. II. (Aschwanden+, 2015)
J/ApJ/831/105 : Global energetics of solar flares. IV. CME (Aschwanden, 2016)
J/ApJ/832/27 : Global energetics of solar flares. III. (Aschwanden+, 2016)
J/ApJ/847/115 : The solar flare complex network (Gheibi+, 2017)
J/ApJ/881/1 : Global energetics of solar flares. VIII. (Aschwanden+, 2019)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- Flare [3/399] Internal flare event number
5- 8 I4 yr Obs.Y [2010/2014] Year of the flare event beginning
10- 11 I2 "month" Obs.M Month of the flare event beginning
13- 14 I2 d Obs.D Day of the flare event beginning
16- 17 I2 h Obs.h Hour of the flare event beginning
19- 20 I2 min Obs.m Minute of the flare event beginning
22- 25 A4 --- GOES GOES classification
27- 32 A6 --- Helio Heliosphere coordinate code
34- 39 F6.1 10+23J Ep [53.4/5403] Potential field energy (1)
41- 46 F6.1 10+23J Enp [56.5/5865] Non-potential energy (1)
48- 52 F5.1 10+23J Efree [0/727] Free energy; Enp-Ep (1)
54- 58 F5.1 10+23J Ediss [0/639] Energy dissipated in flares (1)
60- 64 F5.1 10+23J Ent-e [0/396] Nonthermal energy in accelerated electrons
(1)
66- 70 F5.1 10+23J Ent-i [0/135] Nonthermal energy in accelerated ions (1)
72- 76 F5.1 10+23J Edir [0/216] Direct heating energy (1)
78- 82 F5.1 10+23J Eth [0/216] Thermal energy (1)
84- 88 F5.1 10+23J Ecme [0/620] Coronal mass ejection kinetic energy (1)
90- 94 F5.1 10+23J Esum [0.1/712] Sum of all the energies (1)
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Note (1): In units of 1e+30ergs.
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History:
From electronic version of the journal
References:
Aschwanden et al. Paper I: 2014ApJ...797...50A 2014ApJ...797...50A cat. J/ApJ/797/50
Aschwanden et al. Paper II: 2015ApJ...802...53A 2015ApJ...802...53A cat. J/ApJ/802/53
Aschwanden et al. Paper III: 2016ApJ...832...27A 2016ApJ...832...27A cat. J/ApJ/832/27
Aschwanden et al. Paper IV: 2016ApJ...831..105A 2016ApJ...831..105A cat. J/ApJ/831/105
Aschwanden et al. Paper V: 2017ApJ...836...17A 2017ApJ...836...17A
Aschwanden et al. Paper VI: 2017ApJ...847...27A 2017ApJ...847...27A
Aschwanden et al. Paper VII: 2019ApJ...877..149A 2019ApJ...877..149A
Aschwanden et al. Paper VIII: 2019ApJ...881....1A 2019ApJ...881....1A cat. J/ApJ/881/1
Aschwanden et al. Paper X: 2020ApJ...895..134A 2020ApJ...895..134A
Aschwanden et al. Paper XI: 2020ApJ...897...16A 2020ApJ...897...16A
Aschwanden et al. Paper XII: 2020ApJ...903...23A 2020ApJ...903...23A
(End) Prepared by [AAS], Coralie Fix [CDS], 19-Mar-2021