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Register a new userUnveiling the 100 pc scale nuclear radio structure of NGC 6217 with e-MERLIN and the VLA
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David R. A. Williams
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We present high-sensitivity 1.51 GHz e-MERLIN radio images of the nearby galaxy NGC 6217. We resolve the compact radio source at the centre of NGC 6217 for the first time, finding a twin-lobed structure with a total linear size of ~4 arcsec (~400pc). The radio source does not have a compact central core but there is an unresolved hot spot near the outer edge of the southern lobe. Combining our e-MERLIN data with new VLA A-Array data and archival multi-wavelength data, we explore possible scenarios which might explain this complex radio morphology. We conclude that this radio source is most likely powered by a low-luminosity AGN (LLAGN) but with a possible important contribution from nuclear star formation. We also investigate the origin of a putative X-ray jet in NGC 6217, previously suggested in the literature. This `jet consists of three X-ray `knots in a line, pointed away from the nucleus, with a total size of ~3 arcmin (~15 kpc). We find no extended radio emission coincident with the `jet. An additional compact radio source, aligned with the knots but without an X-ray counterpart is detected. We detect IR/optical sources falling within the X-ray extraction regions of the `knots, but note that these sources could be chance associations due to high source density around the target field and we estimate the probability of three randomly aligned X-ray sources to be 0.3 per cent in this field.
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