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Magnetic Helicity, Tilt, and Twist

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.

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Acknowledgements

The National Solar Observatory (NSO) is operated by the Association of Universities for Research in Astronomy, AURA Inc under cooperative agreement with the National Science Foundation (NSF). AN’s research has been partly co-financed by the European Union (European Social Fund—ESF) and Greek national funds through the Operational Program “Education and Lifelong Learning” of the National Strategic Reference Framework (NSRF)—Research Funding Program: “Thales. Investing in knowledge society through the European Social Fund.” LvDG acknowledges support by STFC Consolidated Grant ST/H00260/1 and the Hungarian Research grants OTKA K-081421 and K-109276. AAP acknowledges support by NASA’s NNH09AL04I inter agency transfer. Data used in Fig. 9 were acquired by SOLIS instruments operated by NISP/NSO/AURA/NSF.

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Pevtsov, A.A., Berger, M.A., Nindos, A. et al. Magnetic Helicity, Tilt, and Twist. Space Sci Rev 186, 285–324 (2014). https://doi.org/10.1007/s11214-014-0082-2

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Keywords

  • Helicity
  • Joy’s law
  • Magnetic field