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Magnetic field strengths in the hot spots of 3C33 and 3C111

M. J. Hardcastle·M. Birkinshaw·D. M. Worrall
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Abstract

We report on ROSAT HRI observations of the nearby powerful radio galaxies 3C33 and 3C111, which both have detected optical hot spots. We find nuclear X-ray sources in both objects, but no X-ray emission from the hot spots. This confirms the presence of a high-energy cutoff in the spectrum of synchrotron-emitting electrons. Since these electrons necessarily scatter the synchrotron photons by the inverse-Compton process, our upper limits on the X-ray fluxes of the hot spots allow us to set lower limits of a few nanotesla on their magnetic flux density, close to or greater than the fields implied by equipartition of energy between radiating particles and magnetic field.

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M. J. Hardcastle, M. Birkinshaw, D. M. Worrall. 1997-09-24. Magnetic field strengths in the hot spots of 3C33 and 3C111. https://doi.org/10.1111/j.1365-8711.1998.01159.x

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