Spectacular 240 kpc double-sided relativistic jets in a spiral-hosted narrow-line Seyfert 1 galaxy

TL;DR

This paper reports the discovery of the largest double-sided relativistic jets in a spiral-hosted narrow-line Seyfert 1 galaxy, challenging previous beliefs about jet formation being exclusive to massive elliptical galaxies.

Contribution

It presents the first observation of extremely large, double-sided relativistic jets in a spiral-hosted NLS1 galaxy, demonstrating that powerful jets can originate from less massive black holes in spiral galaxies.

Findings

Largest double-sided jets in an NLS1 to date.

Jets extend nearly 250 kpc, larger than previously observed in similar galaxies.

Spiral galaxy host confirmed, challenging traditional jet-hosting galaxy models.

Abstract

Narrow-line Seyfert 1 (NLS1) galaxies are a peculiar subclass of active galactic nuclei (AGN). They have demonstrated that the presence of relativistic jets in an AGN is not strictly related to its radio-loudness, the black hole mass, or the host galaxy type. Here we present a remarkable example of a radio-quiet NLS1, 6dFGS gJ035432.8-134008 (J0354-1340). In our Karl G. Jansky Very Large Array observations at 5.5 GHz the source shows a bright core with a flat spectral index, and extended emission corresponding to very elongated jets. These are the largest double-sided radio jets found to date in an NLS1, with a deprojected linear size of almost 250 kpc. We also analysed near-infrared and optical images obtained by the Magellan Baade and the European Southern Observatory New Technology Telescope. By means of photometric decomposition and colour maps, we determined that J0354-1340 is hosted by a spiral/disk galaxy. Fully evolved relativistic jets have traditionally been associated with high-mass elliptical galaxies hosting the most massive black holes, but our results confirm that also less massive black holes in spiral galaxies can launch and sustain powerful jets, implying that the launching of the jets is governed by factors other than previously believed.