Radio jets and gamma-ray emission in radio-silent narrow-line Seyfert 1 galaxies

TL;DR

This study challenges the belief that radio-quiet narrow-line Seyfert 1 galaxies cannot produce jets, by detecting high-frequency radio emissions and gamma rays, indicating the presence of relativistic jets in these galaxies.

Contribution

It provides evidence that radio-quiet NLS1 galaxies can host powerful jets, contradicting previous assumptions based on their radio silence.

Findings

Six radio-quiet NLS1 galaxies detected at 37 GHz

One galaxy identified as a gamma-ray source

Three galaxies are potential future gamma-ray detections

Abstract

We have detected six narrow-line Seyfert 1 (NLS1) galaxies at 37 GHz that were previously classified as radio silent and two that were classified as radio quiet. These detections reveal the presumption that NLS1 galaxies labelled radio quiet or radio silent and hosted by spiral galaxies are unable to launch jets to be incorrect. The detections are a plausible indicator of the presence of a powerful, most likely relativistic jet because this intensity of emission at 37 GHz cannot be explained by, for example, radiation from supernova remnants. Additionally, one of the detected NLS1 galaxies is a newly discovered source of gamma rays and three others are candidates for future detections.