Helicity in the large-scale Galactic magnetic field

@article{West2020HelicityIT,
  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},
  year={2020},
  volume={499},
  pages={3673-3689}
}
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

References

SHOWING 1-10 OF 86 REFERENCES
Planck intermediate results. XLII. Large-scale Galactic magnetic fields
Recent models for the large-scale Galactic magnetic fields in the literature were largely constrained by synchrotron emission and Faraday rotation measures. We select three different butExpand
Constraints from Faraday rotation on the magnetic field structure in the Galactic halo
We examine the constraints imposed by Faraday rotation measures of extragalactic point sources on the structure of the magnetic field in the halo of our Galaxy. Guided by radio polarizationExpand
Modeling the Magnetic Field in the Galactic Disk using New Rotation Measure Observations from the Very Large Array
We have determined 194 Faraday rotation measures (RMs) of polarized extragalactic radio sources using new, multi-channel polarization observations at frequencies around 1.4 GHz from the Very LargeExpand
Galactic dynamos and galactic winds
Spiral galaxies host dynamically important magnetic fields which can affect gas flows in the disks and halos. Total magnetic fields in spiral galaxies are strongest (up to 30 μG) in the spiral armsExpand
Probing magnetic helicity with synchrotron radiation and Faraday rotation
We present a first application of the recently proposed LITMUS test for magnetic helicity, as well as a thorough study of its applicability under different circumstances. In order to apply this testExpand
A New Model of the Galactic Magnetic Field
A new, much-improved model of the Galactic magnetic field (GMF) is presented. We use the WMAP7 Galactic synchrotron emission map and more than 40,000 extragalactic rotation measures to constrain theExpand
The Galactic Halo Magnetic Field Revisited
Recently, Sun et al. published new Galactic 3D-models of magnetic fields in the disk and halo of the Milky Way and the distribution of cosmic-ray electron density by taking into account the thermalExpand
Deriving the Global Structure of the Galactic Magnetic Field from Faraday Rotation Measures of Extragalactic Sources
We made use of the two latest sets of rotational measures (RMs) of extra-galactic radio sources, namely the NRAO VLA Sky Survey rotation measures catalog, and a compilation by Kronberg andExpand
Modelling the Galactic magnetic field on the plane in two dimensions
We present a method for parametric modelling of the physical components of the Galaxy's magnetized interstellar medium, simulating the observables and mapping out the likelihood space using a MarkovExpand
Radio observational constraints on Galactic 3D-emission models
Context. Our position inside the Galaxy requires 3D-modelling to obtain the distribution of the Galactic magnetic field, cosmic- ray (CR) electrons and thermal electrons. Aims. Our intention is toExpand
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