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J. Todd Hoeksema Stanford University

This study explores the causes and effects of superstorms in relation to the magnetic field in the corona and heliosphere. Observations before and after these superstorms reveal changes in the photosphere, the magnetic field, and the heliospheric field. The study also examines the evolution of the magnetic field during these periods and its relationship to active regions and halo CMEs.

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J. Todd Hoeksema Stanford University

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  1. Causes and Effects of SuperstormsAssociated with the Magnetic Field in the Corona and the Heliosphere J. Todd Hoeksema Stanford University

  2. Premonition of Activity 14 Days Before CMP!

  3. Observations of Regions 486 & 488 14D Before Central Meridian 14D Later Far Side

  4. The Photosphere

  5. The Magnetic Field

  6. Another View of the Surface

  7. The Coronal Response Tom Bridgman NASA/Goddard Space Flight Center Scientific Visualization Studio

  8. The Heliospheric Field

  9. The Heliospheric Field

  10. Several Rotations -3 +1 -1 +2 +6 0

  11. Did the open field line connections change? Thanks to Yang Liu at Stanford For the following figures

  12. Evolution of magnetic field in this period Central meridian: CR2007_290** degree in Longitude (Sept. 4) Central meridian: CR2008_290** degree in Longitude (Oct. 1) 0464 0488 Central meridian: CR2009_290** degree in Longitude (Oct. 28) 0484 0486 Central meridian: CR2010_290** degree in Longitude (Nov. 25) 0501 **Not usual 180 centering

  13. Evolution of magnetic field in this period Central meridian: CR2007_290 degree in Longitude (Sept. 4) Central meridian: CR2008_290 degree in Longitude (Oct. 1) 0464 0488 Central meridian: CR2009_290 degree in Longitude (Oct. 28) 0484 0486 Central meridian: CR2010_290 degree in Longitude (Nov. 25) 0501

  14. AR0464 (0484, 0501) and large-scale magnetic field CR2007:290: Sept 4 CR2008:290: Oct 1 0464 0464 0464

  15. AR0486, AR0488 and large-scale magnetic field CR2008:290: Oct 1 CR2009:290: Oct 28 0488 0486

  16. Extremely fast halo CMEs and active regions AR0486, together with AR0488, produced a big open field area after they emerged. AR0464 (a.k.a. 0484, 0501) emerged within/close to an area with large-scale open magnetic field . ? The active regions associated with these high speed halo CMEs are closely associated with sources of already open magnetic flux, except AR0498. In this way the open magnetic field provides an avenue for CMEs to blow out.

  17. AR0498 and large-scale magnetic field CR2009:160 0498

  18. Conclusions • The photospheric field changed dramatically in CR 2009; October 2003 • Numerous dramatic high-speed CME’s blasted through the corona and heliosphere • New flux emerged in such a way as to reinforce the existing structure • New open flux regions had easy access to the heliosphere • The ambient large-scale structure of the heliospheric current sheet changed very little! • This is consistent with earlier results of Zhao & Hoeksema, JGR, 1996.

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