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arXiv · 0901.0167

Blazar nuclei in radio-loud narrow-line Seyfert 1?

L. Foschini·L. Maraschi·F. Tavecchio·G. Ghisellini·M. Gliozzi·R. M. Sambruna
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Abstract

It has been suggested that some radio-loud narrow-line Seyfert 1 contain relativistic jets, on the basis of their flat-spectrum radio nuclei and studies on variability. We present preliminary results of an ongoing investigation of the X-ray and multiwavelength properties of 5 radio-loud NLS1 based on archival data from Swift and XMM-Newton. Some sources present interesting characteristics, very uncharacteristic for a radio-quiet narrow-line Seyfert 1, such as very hard X-ray spectra, and correlated optical and ultraviolet variability. However, none of the studied sources show conclusive evidence for relativistic jets. gamma-ray observations with Fermi are strongly recommended to definitely decide on the presence or not of relativistic jets.

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L. Foschini, L. Maraschi, F. Tavecchio, G. Ghisellini, M. Gliozzi, R. M. Sambruna. 2009-01-01. Blazar nuclei in radio-loud narrow-line Seyfert 1?. https://doi.org/10.1016/j.asr.2008.12.021

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