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Magnetic Helicity, Tilt, and Twist

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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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Authors and Affiliations

  1. National Solar Observatory, Sunspot, USA

    Alexei A. Pevtsov

  2. University of Exeter, Exeter, UK

    Mitchell A. Berger

  3. University of Ioannina, Ipiros, Greece

    Alexander Nindos

  4. Stanford University, Stanford, USA

    Aimee A. Norton

  5. Mullard Space Science Laboratory, University College London, Holmbury St. Mary, Dorking, Surrey, RH5 6NT, UK

    Lidia van Driel-Gesztelyi

  6. Observatoire de Paris, LESIA, FRE 2461 (CNRS), 92195, Meudon Principal Cedex, France

    Lidia van Driel-Gesztelyi

  7. Konkoly Observatory of the Hungarian Academy of Sciences, Budapest, Hungary

    Lidia van Driel-Gesztelyi

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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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