Helicity in the large-scale Galactic magnetic field

  title={Helicity in the large-scale Galactic magnetic field},
  author={J. L. West and R N Henriksen and Katia M. Ferri{\`e}re and Alex Woodfinden and Tess R. Jaffe and Bryan M. Gaensler and Judith A. Irwin},
  journal={Monthly Notices of the Royal Astronomical Society},
We search for observational signatures of magnetic helicity in data from all-sky radio polarization surveys of the Milky Way Galaxy. Such a detection would help confirm the dynamo origin of the field and may provide new observational constraints for its shape. We compare our observational results to simulated observations for both a simple helical field, and for a more complex field that comes from a solution to the dynamo equation. Our simulated observations show that the large-scale helicity… Expand


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