A 60-kpc Galactic Wind Cone in NGC 3079

TL;DR

This paper reports the detection of a large-scale galactic wind in NGC 3079 extending at least 60 kpc, revealing insights into its composition, velocity, and potential impact on galaxy evolution.

Contribution

It presents the first detailed multi-wavelength observations of a galactic wind extending to 60 kpc, providing new data on its properties and implications for galaxy feedback processes.

Findings

Wind detected in FUV and X-ray emissions up to 60 kpc

Wind velocity estimated at about 500 km/s from shock models

Wind's kinetic energy is smaller than in typical hot superwind models

Abstract

Galactic winds are associated with intense star formation and AGNs. Depending on their formation mechanism and velocity they may remove a significant fraction of gas from their host galaxies, thus suppressing star formation, enriching the intergalactic medium, and shaping the circumgalactic gas. However, the long-term evolution of these winds remains mostly unknown. We report the detection of a wind from NGC 3079 to at least 60 kpc from the galaxy. We detect the wind in FUV line emission to 60 kpc (as inferred from the broad FUV filter in GALEX) and in X-rays to at least 30~kpc. The morphology, luminosities, temperatures, and densities indicate that the emission comes from shocked material, and the O/Fe ratio implies that the X-ray emitting gas is enriched by Type II supernovae. If so, the speed inferred from simple shock models is about 500 km/s, which is sufficient to escape the galaxy. However, the inferred kinetic energy in the wind from visible components is substantially smaller than canonical hot superwind models.