DOI QR코드

DOI QR Code

CHROMOSPHERIC MAGNETIC RECONNECTION ON THE SUN

  • CHAE JONGCHUL (Department of Astronomy and Space Science, Chungnam National University) ;
  • CHOI BYUNG-Kyu (Department of Astronomy and Space Science, Chungnam National University) ;
  • PARK MIN-JU (Department of Astronomy and Space Science, Chungnam National University)
  • Published : 2002.03.01

Abstract

Solar observations support that magnetic reconnect ion ubiquitously occurs in the chromosphere as well as in the corona. It is now widely accepted that coronal magnetic reconnect ion is fast reconnect ion of the Petschek type, and is the main driver of solar flares. On the other hand, it has been thought that the traditional Sweet-Parker model may describe chromospheric reconnect ion without difficulty, since the electric conductivity in the chromoshphere is much lower than that in the corona. However, recent observations of cancelling magnetic features have suggested that chromospheric reconnect ion might proceed at a faster rate than the Sweet-Parker model predicts. We have applied the Sweet-Parker model and Petschek model to a well-observed cancelling magnetic feature. As a result, we found that the inflow speed of the Sweet-Parker reconnect ion is too small to explain the observed converging speed of the feature. On the other hand, the inflow speeds and outflow speeds of the Petschek reconnect ion are well compatible with observations. Moreover, we found that the Sweet-Parker type current sheet is subject to the ion-acoustic instability in the chromosphere, implying the Petschek mechanism may operate there. Our results strongly suggest that chromospheric reconnect ion is of the Petschek type.

Keywords

References

  1. Chae, J., Wang, H., Lee, C., Goode, P. R., & Schuhle,U. 1998, Photospheric Magnetic Field Changes Associ-ated with transition Region Explosive Events, ApJ, 497, L109 https://doi.org/10.1086/311289
  2. Chae, J., Qiu, J., Wang, H., & Goode, P. R. 1999, Extreme-Ultraviolet Jets and Halpha Surges in Solar Microflares ,ApJ, 513, L75 https://doi.org/10.1086/311910
  3. Chae, J., Denker, C., Spirock, T. J., Wang, H., & Goode,P. R. 2000, High-Resolution H Observations of Proper Motion in NOAA 8668: Evidence for Filament Mass Injection by Chromospheric Reconnection, Sol. Phys., 195, 333 https://doi.org/10.1023/A:1005242832293
  4. Chae, J., Wang, H., Qiu, J., Goode, P. R., Strous, L., &Yun, H. S. 2001, The Formation of a Prominence in Active Region NOAA 8668. I. SOHO/MDI Observations of Magnetic Field Evolution, ApJ, 560, 476 https://doi.org/10.1086/322491
  5. Chae, J., Moon, Y.-J., Wang, H., & Yun, H. S. 2002a, Flux Cancellation Rates and Converging Speeds of Cancelling Magnetic Features, Sol. Phys., in press
  6. Chae, J., Park, Y. D., Moon, Y. -J., Wang, H., & Yun, H.S. 2002b, Temperatures of EUV-Emitting Plasma Structures Observed by the Transition Region And Coronal Explorer, ApJ, 567, L159 https://doi.org/10.1086/340003
  7. Dere, K. P., Bartoe, J.-D. F., Brueckner, G. E., Ewing, J., & Lund, P. 1991, Explosive events and magnetic reconnection in the solar atmosphere, J. Geophys. Res., 96, 9399 https://doi.org/10.1029/90JA02572
  8. Dere, K. P. 1994, Explosive events, magnetic reconnection, and coronal heating, Adv. Space Res., 14, 13
  9. Feldman, U. 1993, Is it justified to assume that 'Everywherein the sun's photosphere-corona domain the electric Conductivity is HIGH?'; or, what drives the solar upper atmosphere?, ApJ, 411, 896 https://doi.org/10.1086/172894
  10. Harvey, K. L., Jones, H. P., Schrijver, C. J., & Penn, M. J.1999, Does Magnetic Flux Submerge at Flux Cancellation Sites?, Sol. Phys., 190, 35 https://doi.org/10.1023/A:1005237719407
  11. Hermans, L. M., & Martin, S. F. 1986, Small-scale eruptive filaments on the quiet sun, in Coronal and Prominence Plasmas, ed. A. I. Poland (Greenbelt: NASA GoddardSpace Flight Center), 369
  12. Kim, J., Yun, H. S., Lee, S., Chae, J., Goode, P. R., &Wang, H. 2001, A Rapid Change in Magnetic Connectivity Observed Before Filament Eruption and Its Assodated Flare, ApJ, 547, L85 https://doi.org/10.1086/318883
  13. Kovitya, P., & Cram, L. 1983, Electrical conductivity in sunspots and the quiet photosphere, Sol. Phys., 84, 45 https://doi.org/10.1007/BF00157441
  14. Kubat, J., &: Karlicky, M. 1986, Electrical conductivity in the solar photosphere and chromosphere, Bull. Astron.l Inst. Czechoslovakia, 37, 155
  15. Lee, C., Chae, J., & Wang, H. 2000, Dynamical Characteristics of Small-Scale Ha Upflow Events on the Quiet Sun, ApJ, 545, 1124 https://doi.org/10.1086/317821
  16. Lin, H. 1995, On the Distribution of the Solar Magnetic Fields, ApJ, 446, 421 https://doi.org/10.1086/175800
  17. Lisle, J., De Rosa, M., &; Toomre, J., 2000, New Approach to Study Extended Evolution of Supergranular Flows and Their Advection of Magnetic Elements, Sol. Phys., 197, 21 https://doi.org/10.1023/A:1026556721220
  18. Litvinenko, Y. 1999, Photospheric Magnetic Reconnection and Canceling Magnetic Features on the Sun, ApJ, 515, 435 https://doi.org/10.1086/307001
  19. Litvinenko, Y., & Martin, S. F. 1999, Magnetic reconnection as the cause of a photospheric canceling feature and mass flows in a filament, Sol. Phys., 190, 45 https://doi.org/10.1023/A:1005284116353
  20. Livi, S. H. B., Wang, J., & Martin, S. F. 1985, The cancallation of magnetic flux. I - On the quiet sun, Australian J. Phys., 38, 855 https://doi.org/10.1071/PH850855
  21. Livi, S. H. B., Martin, S., Wang, H., & Ai, G. 1989,, The association of flares to cancelling magnetic features on the sun, Sol. Phys., 121, 197
  22. Martin, S. F. 1986, Recent observations of the formation of filaments, in Coronal and Prominence Plasmas, ed. A. I. Poland (Greenbelt: NASA Goddard Space Flight Center), 73
  23. Martin, S. F. 1990, Small-Scale Magnetic Features Observed in the Photosphere, in IAU Symp. 138, Solar Photosphere: Structure, Convection and Magnetic Fields, ed. J. O. Stenflo (Dordrecht:Kluwer Academic Publishers), 129
  24. Martin, S. F., Livi, S. H. B., & Wang, J. 1985, The Cancellation of magnetic flux. II - In a decaying active region, Australian J. Phys., 38, 929 https://doi.org/10.1071/PH850929
  25. Parker, E. N. 1957, Sweet's Mechanism for Merging Magnetic Fields in Conducting Fluids, J. Geophys. Res., 62, 509 https://doi.org/10.1029/JZ062i004p00509
  26. Petschek, H. E. 1964, Magnetic Field Annihilation, in Physics of Solar Flares, ed. W. H. Hess (Washington, DC: NASA SP-50), 425
  27. Priest, E. & Forbes, T. 2000, Magnetic Reconnection: MHDTheory and Applications (Cambridge: Cambridge University Press)
  28. Scholer, M. 1989, Undriven magnetic recoimection in an isolated current sheet, J. Geophys. Res., 94, 8805 https://doi.org/10.1029/JA094iA07p08805
  29. Stenflo, J. O. 1985, Measurements of magnetic fields and the analysis of Stokes profiles, Sol. Phys., 100, 189 https://doi.org/10.1007/BF00158428
  30. Sturrock, P. A. 1999, Chromospheric Magnetic Reconnection and Its Possible Relationship to Coronal Heating, ApJ, 521, 451 https://doi.org/10.1086/307544
  31. Sweet, P. A. 1958, The Neutral Point Theory of Solar Flares, in IAU Symp. 6, Electromagnetic Phenomena in Cosmical Physics, ed. B. Lehnert (London: Cambridge University Press), 123
  32. Ugai, M. 1984, Self-consistent development of fast magnetic reconnection with anomalous plasma resitivity, Plasma Phys. Control. Fusion, 26, 1549 https://doi.org/10.1088/0741-3335/26/12B/010
  33. Vernazza, J. E., Avrett, E. H., & Loeser, R. 1981, Structure of the solar chromosphere. III - Models of the EUV brightness components of the quiet-sun, ApJS, 45, 635 https://doi.org/10.1086/190731
  34. Wang, J. 1993, Electric Conductivity of Lower Solar Atmosphere, in ASP Conf. Ser. 46, The Magnetic and Velocity Fields of Solar Active Regions, ed. H. Zirin, G. Ai, & H. Wang (San Francisco: ASP), 465
  35. Wang, J., & Shi, Z. 1993, The flare-associated magnetic changes in an active region. II - Flux emergence and cancellation, Sol. Phys., 143, 119 https://doi.org/10.1007/BF00619100
  36. Wang, J., Shi, Z., & Martin, S. F. 1996, Filament distur-bance and associated magnetic changes in the filamentenvironment, A&A, 316, 201
  37. Wang, H., & Zirin, H. 1988, The velocity pattern of weak solar magnetic fields, Sol. Phys., 115, 205 https://doi.org/10.1007/BF00148723
  38. Webb, D. F., Martin, S. F., Moses, D., & Harvey, J. W. 1993, The correspondence between X-ray bright points and evolving magnetic features in the quiet sun, Sol. Phys., 144, 15 https://doi.org/10.1007/BF00667979
  39. Yokoyama, T. & Shibata, K. 1994, What is the condition for fast magnetic reconnection?, ApJ, 436, L197 https://doi.org/10.1086/187666
  40. Zhang, J., Wang, J., Deng, Y., & Wu, D. 2001, Magnetic Flux Cancellation Associated with the Major Solar Event on 2000 July 14, ApJ, 548, L99 https://doi.org/10.1086/318934

Cited by

  1. CDS wide slit time-series of EUV coronal bright points vol.425, pp.3, 2004, https://doi.org/10.1051/0004-6361:20041069
  2. Reconnection in solar flares: Outstanding questions vol.30, pp.2, 2009, https://doi.org/10.1007/s12036-009-0007-8
  3. Determination of Magnetic Diffusivity from High‐Resolution Solar Magnetograms vol.683, pp.2, 2008, https://doi.org/10.1086/590074
  4. NEW SOLAR TELESCOPE OBSERVATIONS OF MAGNETIC RECONNECTION OCCURRING IN THE CHROMOSPHERE OF THE QUIET SUN vol.713, pp.1, 2010, https://doi.org/10.1088/2041-8205/713/1/L6
  5. Convection-driven Emergence of Small-Scale Magnetic Fields and their Role in Coronal Heating and Solar Wind Acceleration vol.679, pp.1, 2008, https://doi.org/10.1086/589150
  6. High speed magnetized flows in the quiet Sun vol.569, 2014, https://doi.org/10.1051/0004-6361/201424131
  7. Possible two-step solar energy release mechanism due to turbulent magnetic reconnection vol.12, pp.5, 2005, https://doi.org/10.1063/1.1862249