Space Science Reviews

, Volume 186, Issue 1–4, pp 285–324 | Cite as

Magnetic Helicity, Tilt, and Twist

  • Alexei A. PevtsovEmail author
  • Mitchell A. Berger
  • Alexander Nindos
  • Aimee A. Norton
  • Lidia van Driel-Gesztelyi


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.


Helicity Joy’s law Magnetic field 



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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Copyright information

© Springer Science+Business Media Dordrecht 2014

Authors and Affiliations

  • Alexei A. Pevtsov
    • 1
    Email author
  • 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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