SPICE-RACS DR2 delivers the largest single Faraday rotation measure catalog from a radio survey, with 250,000-340,000 RMs across most of the sky at median uncertainty of 2 rad m^{-2}.
Magnetic Fields in Large Diameter HII Regions Revealed by the Faraday Rotation of Compact Extragalactic Radio Sources
4 Pith papers cite this work. Polarity classification is still indexing.
abstract
We present a study of the line-of-sight magnetic fields in five large-diameter Galactic HII regions. Using the Faraday rotation of background polarized radio sources, as well as dust-corrected H-alpha surface brightness as a probe of electron density, we estimated the strength and orientation of the magnetic field along 93 individual sight-lines through the HII regions. Each of the HII regions displayed a coherent magnetic field. The magnetic field strength (line-of-sight component) in the regions ranges from 2 to 6 microgauss, which is similar to the typical magnetic field strength in the diffuse interstellar medium. We investigated the relationship between magnetic field strength and electron density in the 5 HII regions. The slope of magnetic field vs. density in the low-density regime (0.8 < n_e < 30 per cubic cm) is very slightly above zero. We also calculated the ratio of thermal to magnetic pressure, beta_th, for each data point, which fell in the range 1.01 < beta_th < 25. Finally, we studied the orientation of the magnetic field in the solar neighborhood (d < 1.1 kpc) using our data from 5 HII regions along with existing measurements of the line-of-sight magnetic field strength from polarized pulsars whose distances have been determined from their annual parallax. We identify a net direction for the magnetic field in the solar neighborhood, but find no evidence for a preferred vertical direction of the magnetic field above or below the Galactic plane.
fields
astro-ph.GA 4years
2026 4verdicts
UNVERDICTED 4representative citing papers
Comparison of Galactic magnetic field models to polarized synchrotron observations shows good agreement on angles but poor match on intensity, indicating local foreground structures must be incorporated.
Review chapter summarizing the importance of small-scale galactic magnetic fields and proposing SKA observation strategies.
Review summarizing observational data on the Milky Way's magnetic field structure, including spiral alignment, halo components, turbulence, and correlations with interstellar gas and dust.
citing papers explorer
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The Rapid ASKAP Continuum Survey VII: Spectra and Polarisation In Cutouts of Extragalactic Sources (SPICE-RACS) Second Data Release -- Unveiling the Magnetised Sky
SPICE-RACS DR2 delivers the largest single Faraday rotation measure catalog from a radio survey, with 250,000-340,000 RMs across most of the sky at median uncertainty of 2 rad m^{-2}.
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A comparison between Galactic magnetic field models and polarized synchrotron emission with C-BASS at 4.76 GHz and S-PASS at 2.3 GHz
Comparison of Galactic magnetic field models to polarized synchrotron observations shows good agreement on angles but poor match on intensity, indicating local foreground structures must be incorporated.
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Small-scale Magnetic Fields in the Milky Way and Nearby Galaxies
Review chapter summarizing the importance of small-scale galactic magnetic fields and proposing SKA observation strategies.
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The magnetic field of the Milky Way: an observational perspective
Review summarizing observational data on the Milky Way's magnetic field structure, including spiral alignment, halo components, turbulence, and correlations with interstellar gas and dust.