Journal of The Korean Astronomical Society (천문학회지)

The Korean Astronomical Society (한국천문학회)
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AN INVERSION METHOD FOR DERIVING PHYSICAL PROPERTIES OF A SUBSURFACE MAGNETIC FIELD FROM SURFACE MAGNETIC FIELD EVOLUTION I. APPLICATION TO SIMULATED DATA

  • Magara, Tetsuya (Department of Astronomy and Space Science, School of Space Research, Kyung Hee University)
  • Received : 2017.10.28
  • Accepted : 2017.11.18
  • Published : 2017.12.31
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Abstract

We present a new method for solving an inverse problem of flux emergence which transports subsurface magnetic flux from an inaccessible interior to the surface where magnetic structures may be observed to form, such as solar active regions. To make a quantitative evaluation of magnetic structures having various characteristics, we derive physical properties of subsurface magnetic field that characterize those structures formed through flux emergence. The derivation is performed by inversion from an evolutionary relation between two observables obtained at the surface, emerged magnetic flux and injected magnetic helicity, the former of which provides scale information while the latter represents the configuration of magnetic field.

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References

  1. Berger, M. A., & Field, G. B. 1984, The Topological Properties of Magnetic Helicity, Journal of Fluid Mechanics, 147, 133 https://doi.org/10.1017/S0022112084002019
  2. Chae, J. 2001, Observational Determination of the Rate of Magnetic Helicity Transport through the Solar Surface via the Horizontal Motion of Field Line Footpoints, ApJ, 560, L95 https://doi.org/10.1086/324173
  3. Choudhuri, A. R., Chatterjee, P., & Jiang, J. 2007, Predicting Solar Cycle 24 With a Solar Dynamo Model, Physical Review Letters, 98, 131103 https://doi.org/10.1103/PhysRevLett.98.131103
  4. Demoulin, P., & Berger, M. A. 2003, Magnetic Energy and Helicity Fluxes at the Photospheric Level, Solar Physics, 215, 203 https://doi.org/10.1023/A:1025679813955
  5. Fan, Y. 2009, Magnetic Fields in the Solar Convection Zone, Living Reviews in Solar Physics, 6, 4
  6. Finn, J. M., & Antonsen, T. M. 1985, Magnetic Helicity: What Is It, and What Is It Good for?, Comments Plasma Phys. Controlled Fusion, 26, 111
  7. Gold, T., & Hoyle, F. 1960, On the Origin of Solar Flares, MNRAS, 120, 89 https://doi.org/10.1093/mnras/120.2.89
  8. Jeong, H., & Chae, J. 2007, Magnetic Helicity Injection in Active Regions, ApJ, 671, 1022 https://doi.org/10.1086/522666
  9. Kliem, B., & Torok, T. 2006, Torus Instability, Physical Review Letters, 96, 255002 https://doi.org/10.1103/PhysRevLett.96.255002
  10. Kusano, K., Maeshiro, T., Yokoyama, T., & Sakurai, T. 2002, Measurement of Magnetic Helicity Injection and Free Energy Loading into the Solar Corona, ApJ, 577, 501 https://doi.org/10.1086/342171
  11. Low, B. C. 1996, Solar Activity and the Corona, Solar Physics, 167, 217 https://doi.org/10.1007/BF00146338
  12. Magara, T. 2004, Injection of Magnetic Energy and Magnetic Helicity into the Solar Atmosphere by an Emerging Magnetic Flux Tube, The Solar-B Mission and the Forefront of Solar Physics, ASPC, 325, 185
  13. Magara, T., & Tsuneta, S. 2008, Hinode's Observational Result on the Saturation of Magnetic Helicity Injected into the Solar Atmosphere and Its Relation to the Occurrence of a Solar Flare, Publication of Astronomical Society of Japan, 60, 1181 https://doi.org/10.1093/pasj/60.5.1181
  14. Magara, T. 2012, How Much Does a Magnetic Flux Tube Emerge into the Solar Atmosphere?, ApJ, 748, 53 https://doi.org/10.1088/0004-637X/748/1/53
  15. Moreno-Insertis, F., & Emonet, T. 1996, The Rise of Twisted Magnetic Tubes in a Strati ed Medium, ApJ, 472, L53 https://doi.org/10.1086/310360
  16. Parker, E. N. 1955, The Formation of Sunspots from the Solar Toroidal Field, ApJ, 121, 491 https://doi.org/10.1086/146010
  17. Priest, E. R., & Forbes, T. G. 2000, Magnetic Reconnection: MHD Theory and Applications (Cambridge: Cambridge University Press), 268
  18. Priest, E. R., & Forbes, T. G. 2002, The Magnetic Nature of Solar Flares, A&SR, 10, 313
  19. Schwabe, M. 1844, Sonnenbeobachtungen im Jahre 1843. Von Herrn Hofrath Schwabe in Dessau, Astronomische Nachrichten, 21, 233 https://doi.org/10.1002/asna.18440211504
  20. Shibata, K., & Magara, T. 2011, Solar Flares: Magnetohydrodynamic Processes, Living Reviews in Solar Physics, 8, 6