Location via proxy:   [ UP ]  
[Report a bug]   [Manage cookies]                
Skip to main content

Solar Sector Structure

  • Published:
Space Science Reviews Aims and scope Submit manuscript

Abstract

The interplanetary magnetic field near 1 AU has a characteristic “sector” structure that reflects its polarity relative to the solar direction. Typically we observe large-scale coherence in these directions, with two or four “away” or “towards” sectors per solar rotation, from any platform in deep space and near the ecliptic plane. In a simple picture, this morphology simply reflects the idea that the sources of the interplanetary field lie mainly in or near the Sun, and that the solar-wind flow enforces a radial component in this field. The sector boundaries are sharply defined in the interplanetary field near one AU, but have more complicated sources within the Sun itself. Recent evidence confirms that the origins of this pattern also appear statistically at the level of the photosphere, with signatures found in the highly concentrated fields of sunspots and even solar flares. This complements the associations already known between the interplanetary sectors and large-scale coronal structures (i.e., the streamers). This association with small-scale fields strengthens at the Hale sector boundary, defining the Hale boundary as the one for which the polarity switch matches that of the leading-to-following polarity alternation in the sunspots of a given hemisphere. Surface features that appear 4.5 days prior to the sector crossings observed at 1 AU correlate with this sense of polarity reversal.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Subscribe and save

Springer+ Basic
$34.99 /Month
  • Get 10 units per month
  • Download Article/Chapter or eBook
  • 1 Unit = 1 Article or 1 Chapter
  • Cancel anytime
Subscribe now

Buy Now

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9
Fig. 10
Fig. 11

Similar content being viewed by others

Notes

  1. http://www.leif.org/research/sblist.txt.

References

Download references

Acknowledgements

We thank the International Space Science Institute for support during the preparation of this chapter. Author Hudson thanks NASA for support under contract NAS 5-98033 for RHESSI, and acknowledges hospitality at the University of Glasgow.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Hugh S. Hudson.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Hudson, H.S., Svalgaard, L. & Hannah, I.G. Solar Sector Structure. Space Sci Rev 186, 17–34 (2014). https://doi.org/10.1007/s11214-014-0121-z

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s11214-014-0121-z

Keywords