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Gigahertz-Peaked Spectrum Radio Sources in Nearby Galaxies

N. M. Nagar·A. S. Wilson·H. Falcke·J. S. Ulvestad·C. G. Mundell
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Abstract

There is now strong evidence that many low-luminosity AGNs (LLAGNs) contain accreting massive black holes and that the nuclear radio emission is dominated by parsec-scale jets launched by these black holes. Here, we present preliminary results on the 1.4 GHz to 667 GHz spectral shape of a well-defined sample of 16 LLAGNs. The LLAGNs have a falling spectrum at high GHz frequencies. Several also show a low-frequency turnover with a peak in the 1-20 GHz range. The results provide further support for jet dominance of the core radio emission. The LLAGNs show intriguing similarities with gigahertz-peaked spectrum (GPS) sources.

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N. M. Nagar, A. S. Wilson, H. Falcke, J. S. Ulvestad, C. G. Mundell. 2002-01-10. Gigahertz-Peaked Spectrum Radio Sources in Nearby Galaxies. https://arxiv.org/abs/astro-ph/0201156

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