First Science with SAMI: A Serendipitously Discovered Galactic Wind in ESO 185-G031

TL;DR

The SAMI instrument's first scientific results include discovering a galactic wind in ESO 185-G031, highlighting the potential of multi-object fiber spectroscopy for detecting extended galactic phenomena beyond nuclear regions.

Contribution

This study demonstrates the capability of the SAMI multi-object integral field spectrograph to identify extended galactic winds, revealing activity often missed by traditional single-fiber spectroscopy.

Findings

Detection of a large-scale galactic wind in ESO 185-G031

Multi-object fiber spectroscopy can uncover extranuclear activity

Galactic winds may be more common than previously thought

Abstract

We present the first scientific results from the Sydney-AAO Multi-Object IFS (SAMI) at the Anglo-Australian Telescope. This unique instrument deploys 13 fused fibre bundles (hexabundles) across a one-degree field of view allowing simultaneous spatially-resolved spectroscopy of 13 galaxies. During the first SAMI commissioning run, targeting a single galaxy field, one object (ESO 185-G031) was found to have extended minor axis emission with ionisation and kinematic properties consistent with a large-scale galactic wind. The importance of this result is two-fold: (i) fibre bundle spectrographs are able to identify low-surface brightness emission arising from extranuclear activity; (ii) such activity may be more common than presently assumed because conventional multi-object spectrographs use single-aperture fibres and spectra from these are nearly always dominated by nuclear emission. These early results demonstrate the extraordinary potential of multi-object hexabundle spectroscopy in future galaxy surveys.