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

TL;DR

This study investigates the X-ray and multiwavelength properties of five radio-loud narrow-line Seyfert 1 galaxies to assess the presence of relativistic jets, finding some unusual features but no conclusive jet evidence.

Contribution

It provides preliminary multiwavelength analysis of radio-loud NLS1 galaxies, highlighting their unique properties and the need for gamma-ray observations to confirm jet presence.

Findings

Some sources show very hard X-ray spectra.

Optical and ultraviolet variability are observed.

No conclusive evidence of relativistic jets is found.

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.