Recent studies indicate that measurements of fractal and multifractal parameters of active regions (ARs) are inefficient tools for distinguishing ARs on the basis of the flare activity or to predict flare events. In an attempt to validate this result on a large observation data set of higher spatial and temporal resolution and higher flux sensitivity than employed in previous studies, we analyzed high-cadence time series of line-of-sight magnetograms of 43 ARs characterized by different flare activity, which were observed with SDO/HMI from May 2010 to December 2013. On these data, we estimated four parameters, the generalized fractal dimensions D 0 and D 8, and the multifractal parameters C div and D div. We found distinct average values of the parameters measured on ARs that have hosted flares of different class. However, the dispersion of values measured on ARs that have produced the same class of events is such that the parameters deduced from distinct classes of flaring regions can also largely overlap. Based on the results of our measurements, C- and M-class flaring ARs are practically indistinguishable, and the same is true for M- and X-class flaring ARs. We only found consistent changes on the time series of the measured parameters on ≈ 50 % of the ARs and ≈ 50 % of the M- and X-class events. We show that these results hold for fractal and multifractal parameter estimates based on total unsigned and signed flux data of the ARs.
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Abramenko, V.I.: 2005, Multifractal analysis of solar magnetograms. Solar Phys. 228, 29. DOI .
Barnes, G., Leka, K.D.: 2008, Evaluating the performance of solar flare forecasting methods. Astrophys. J. Lett. 688, L107. DOI .
Burtseva, O., Petrie, G.: 2013, Magnetic flux changes and cancellation associated with X-class and M-class flares. Solar Phys. 283, 429. DOI .
Cliver, E.W., Petrie, G.J.D., Ling, A.G.: 2012, Abrupt changes of the photospheric magnetic field in active regions and the impulsive phase of solar flares. Astrophys. J. 756, 144. DOI .
Conlon, P.A., Gallagher, P.T., McAteer, R.T.J., Ireland, J., Young, C.A., Kestener, P., Hewett, R.J., Maguire, K.: 2008, Multifractal properties of evolving active regions. Solar Phys. 248, 297. DOI .
Criscuoli, S., Rast, M.P., Ermolli, I., Centrone, M.: 2007, On the reliability of the fractal dimension measure of solar magnetic features and on its variation with solar activity. Astron. Astrophys. 461, 331. DOI .
Criscuoli, S., Romano, P., Giorgi, F., Zuccarello, F.: 2009, Magnetic evolution of superactive regions. Complexity and potentially unstable magnetic discontinuities. Astron. Astrophys. 506, 1429. DOI .
Ermolli, I., Giorgi, F., Romano, P., Zuccarello, F., Criscuoli, S., Stangalini, M.: 2014, Fractal and multifractal properties of active regions as flare precursors: A case study based on SOHO/MDI and SDO/HMI observations. Solar Phys. 289, 2525. DOI .
Fan, Y.: 2009, Magnetic fields in the solar convection zone. Living Rev. Solar Phys. 6(4). DOI .
Georgoulis, M.K.: 2005, Turbulence in the solar atmosphere: Manifestations and diagnostics via solar image processing. Solar Phys. 228, 5. DOI .
Georgoulis, M.K.: 2012, Are solar active regions with major flares more fractal, multifractal, or turbulent than others? Solar Phys. 276, 161. DOI .
Georgoulis, M.K.: 2013, Toward an efficient prediction of solar flares: Which parameters, and how? Entropy 15, 5022. DOI .
Giannattasio, F., Stangalini, M., Del Moro, D., Berrilli, F.: 2013, On the asymmetry of velocity oscillation amplitude in bipolar active regions. Astron. Astrophys. 550, A47. DOI .
Hapgood, M.: 2012, Astrophysics: Prepare for the coming space weather storm. Nature 484, 311. DOI .
Leka, K.D., Barnes, G.: 2013, Solar flare forecasting: A ”state of the field” report for researchers. Bull. Am. Astron. Soc. 45, 100.82.
Li, Y., Luhmann, J., Fisher, G., Welsch, B.: 2004, Observational evidence for velocity convergence toward magnetic neutral lines as a factor in CME initiation. J. Atmos. Solar-Terr. Phys. 66, 1271. DOI .
McAteer, R.T.J., Gallagher, P.T., Ireland, J.: 2005, Statistics of active region complexity: A large-scale fractal dimension survey. Astrophys. J. 631, 628. DOI .
Romano, P., Zuccarello, F.: 2011, Flare occurrence and the spatial distribution of the magnetic helicity flux. Astron. Astrophys. 535, A1. DOI .
Sammis, I., Tang, F., Zirin, H.: 2000, The dependence of large flare occurrence on the magnetic structure of sunspots. Astrophys. J. 540, 583. DOI .
Shibata, K., Magara, T.: 2011, Solar flares: Magnetohydrodynamic processes. Living Rev. Solar Phys. 8, 6. DOI .
Scherrer, P.H., Bogart, R.S., Bush, R.I., Hoeksema, J.T., Kosovichev, A.G., Schou, J., Rosenberg, W., Springer, L., Tarbell, T.D., Title, A., Wolfson, C.J., Zayer, I. (MDI Engineering Team): 1995, The Solar Oscillations Investigation – Michelson Doppler Imager. Solar Phys. 162, 129. DOI .
Scherrer, P.H., Schou, J., Bush, R.I., Kosovichev, A.G., Bogart, R.S., Hoeksema, J.T., Liu, Y., Duvall, T.L., Zhao, J., Title, A.M., Schrijver, C.J., Tarbell, T.D., Tomczyk, S.: 2012, The Helioseismic and Magnetic Imager (HMI) investigation for the Solar Dynamics Observatory (SDO). Solar Phys. 275, 207. DOI .
Schou, J., Scherrer, P.H., Bush, R.I., Wachter, R., Couvidat, S., Rabello-Soares, M.C., Bogart, R.S., Hoeksema, J.T., Liu, Y., Duvall, T.L., Akin, D.J., Allard, B.A., Miles, J.W., Rairden, R., Shine, R.A., Tarbell, T.D., Title, A.M., Wolfson, C.J., Elmore, D.F., Norton, A.A., Tomczyk, S.: 2012, Design and ground calibration of the Helioseismic and Magnetic Imager (HMI) instrument on the Solar Dynamics Observatory (SDO). Solar Phys. 275, 229. DOI .
Wachter, R., Schou, J., Rabello-Soares, M.C., Miles, J.W., Duvall, T.L., Bush, R.I.: 2012, Image quality of the Helioseismic and Magnetic Imager (HMI) onboard the Solar Dynamics Observatory (SDO). Solar Phys. 275, 261. DOI .
Yamamoto, T.T.: 2012, The area asymmetry in bipolar magnetic fields. Astron. Astrophys. 539, A13. DOI .
The research leading to these results has received funding from the European Commission’s Seventh Framework Programme (FP7/2007-2013) under the grant agreements eHEROES (project no. 284461, www.eheroes.eu ) and SOLARNET (no. 312495, www.solarnet-east.eu ). This work was also supported by the Istituto Nazionale di Astrofisica (PRIN-INAF-2010). The authors acknowledge useful discussions from Giuseppe Consolini and Gherardo Valori.
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Giorgi, F., Ermolli, I., Romano, P. et al. The Signature of Flare Activity in Multifractal Measurements of Active Regions Observed by SDO/HMI. Sol Phys 290, 507–525 (2015). https://doi.org/10.1007/s11207-014-0609-4
- Flares, forecasting
- Flares, relation to magnetic field
- Magnetic fields, photosphere