A (likely) X-ray jet from NGC6217 observed by XMM-Newton

TL;DR

This study confirms a potential X-ray jet in NGC6217, a spiral galaxy with a low-luminosity AGN, challenging existing notions of jet-host galaxy associations and suggesting an advection dominated accretion flow as a possible mechanism.

Contribution

First detailed X-ray analysis of a candidate jet in NGC6217, revealing spectral properties and host galaxy context that challenge traditional jet-host paradigms.

Findings

Confirmed X-ray knots aligned with galaxy center

Spectral analysis shows similar properties with Gamma~1.7

Jet candidate length ~15 kpc with luminosity ~5x10^38 erg/s

Abstract

NGC6217 is a nearby spiral galaxy with a starburst region near its center. Evidence for a low luminosity Active Galactic Nucleus (AGN) in its core has also been found in optical spectra. Intriguingly, X-ray observations by ROSAT revealed three knots aligned with the galaxy center, resembling a jet structure. This paper presents a study of XMM-Newton observations made to assess the hypothesis of a jet emitted from the center of NGC6217. The XMM data confirm the knots found with ROSAT and our spectral analysis shows that they have similar spectral properties with a hard photon index Gamma~1.7. The core of NGC6217 is well fitted by a model with an AGN and a starburst component, where the AGN contributes at most 46% of the total flux. The candidate jet has an apparent length ~15 kpc and a luminosity of ~5 X 10^38 erg/s. It stands out by being hosted by a spiral galaxy, since jets are more widely associated with ellipticals. To explain the jet launching mechanism we consider the hypothesis of an advection dominated accretion flow with a low accretion rate. The candidate jet emitted from NGC6217 is intriguing since it represents a challenge to the current knowledge of the connection between AGN, jets and host galaxies.