Photospheric Magnetic Free Energy Density of Solar Active Regions
arXiv:1608.07805 · doi:10.1007/s11207-016-1009-8
Abstract
We present the photospheric energy density of magnetic fields in two solar active regions inferred from observational vector magnetograms, and compare it with the possible different defined energy parameters of magnetic fields in the photosphere. We analyze the magnetic fields in active region NOAA 6580-6619-6659 and 11158. It is noticed that the quantity 1/4pi Bn.Bp is an important energy parameter that reflects the contribution of magnetic shear on the difference between the potential magnetic field (Bp) and non-potential one (Bn), and also the contribution to the free magnetic energy near the magnetic neutral lines in the active regions. It is found that the photospheric mean magnetic energy density changes obviously before the powerful solar flares in the active region NOAA 11158, it is consistent with the change of magnetic fields in the lower atmosphere with flares.
arXiv commentsubmit 20 pages, 12 figures, Solar Physics, 2016
References in corpus (23)
- Evolution of Magnetic Field and Energy in A Major Eruptive Active Region Based on SDO/HMI Observation
- Extrapolation of the Solar Coronal Magnetic Field from SDO/HMI Magnetogram by a CESE--MHD--NLFFF Code
- On the Role of Rotating Sunspots in the Activity of Solar Active Region NOAA 11158
- Interpreting Eruptive Behavior in NOAA AR 11158 via the Region's Magnetic Energy and Relative Helicity Budgets
- Abrupt changes in photospheric magnetic and Lorentz-force vectors during neutral-line flares
- Evidence for collapsing fields in corona and photosphere during the 15 February 2011 X2.2 flare: SDO AIA and HMI Observations
- Using Coronal Loops to Reconstruct the Magnetic Field of an Active Region Before and After a Major Flare
- Study on Triggering Process of Solar Flares Based on Hinode/SOT Observations
- On the injection of helicity by shearing motion of fluxes in relation to Flares and CMEs
- Magnetic Structure Producing X- and M-Class Solar Flares in Solar Active Region 11158
- Magnetic Systems Triggering the M6.6-class Solar Flare in NOAA Active Region 11158
- Temporal Evolution of the Magnetic Topology of the NOAA Active Region 11158
- Photospheric Electric Fields and Energy Fluxes in the Eruptive Active Region NOAA 11158
- Velocity and Magnetic Transients Driven by the X2.2 White-Light Flare of 2011 February 15 in NOAA 11158
- The Magnetic Field of Active Region 11158 During the 2011 February 12-17 Flares : Differences between Photospheric Extrapolation and Coronal Forward-Fitting Methods
- First observational application of a connectivity--based helicity flux density
- Evolution of Magnetic Helicity and Energy Spectra of Solar Active Regions
- A Statistical Study on Photospheric Magnetic Nonpotentiality of Active Regions and Its Relationship with Flares during Solar Cycles 22-23
- Calculating Separate Magnetic Free Energy Estimates for Active Regions Producing Multiple Flares: NOAA AR11158
- Flares and Magnetic Non-potentiality of NOAA AR 11158
- Sign singularity and flares in solar active region NOAA 11158
- 3-D nonlinear force-free field reconstruction of solar active region 11158 by direct boundary integral equation
- Spatio-temporal scaling of turbulent photospheric line-of-sight magnetic field in active region NOAA 11158