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Magnetic Helicity, Tilt, and Twist

  • Alexei A. Pevtsov
  • Mitchell A. Berger
  • Alexander Nindos
  • Aimee A. Norton
  • Lidia van Driel-Gesztelyi
Part of the Space Sciences Series of ISSI book series (SSSI, volume 53)

Abstract

Since its introduction to astro- and solar physics, the concept of helicity has proven to be useful in providing critical insights into physics of various processes from astrophysical dynamos, to magnetic reconnection and eruptive phenomena. Signature of helicity was also detected in many solar features, including orientation of solar active regions, or Joy’s law. Here we provide a summary of both solar phenomena and consider mutual relationship and its importance for the evolution of solar magnetic fields.

Keywords

Helicity Joy’s law Magnetic field 

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Copyright information

© Springer Science+Business Media New York 2015

Authors and Affiliations

  • Alexei A. Pevtsov
    • 1
  • Mitchell A. Berger
    • 2
  • Alexander Nindos
    • 3
  • Aimee A. Norton
    • 4
  • Lidia van Driel-Gesztelyi
    • 5
    • 6
    • 7
  1. 1.National Solar ObservatorySunspotUSA
  2. 2.University of ExeterExeterUK
  3. 3.University of IoanninaIpirosGreece
  4. 4.Stanford UniversityStanfordUSA
  5. 5.Mullard Space Science LaboratoryUniversity College LondonHolmbury St. Mary, DorkingUK
  6. 6.Observatoire de ParisLESIA, FRE 2461 (CNRS)Meudon Principal CedexFrance
  7. 7.Konkoly Observatory of the Hungarian Academy of SciencesBudapestHungary

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