The Sydney-AAO Multi-object Integral field spectrograph (SAMI)

TL;DR

SAMI is a novel multi-object integral field spectrograph that enables spatially-resolved spectroscopy of many galaxies simultaneously, combining wide-field coverage with detailed spectral information.

Contribution

It introduces a new multi-object IFS technology with hexabundles, allowing high multiplexing and spatial resolution over large fields at the AAT.

Findings

First spectroscopic results for galaxies at z~0.05.

Demonstrated capability of 13 hexabundles over 1-degree field.

Potential for large-scale spatially-resolved galaxy surveys.

Abstract

We demonstrate a novel technology that combines the power of the multi-object spectrograph with the spatial multiplex advantage of an integral field spectrograph (IFS). The Sydney-AAO Multi-object IFS (SAMI) is a prototype wide-field system at the Anglo-Australian Telescope (AAT) that allows 13 imaging fibre bundles ("hexabundles") to be deployed over a 1-degree diameter field of view. Each hexabundle comprises 61 lightly-fused multimode fibres with reduced cladding and yields a 75 percent filling factor. Each fibre core diameter subtends 1.6 arcseconds on the sky and each hexabundle has a field of view of 15 arcseconds diameter. The fibres are fed to the flexible AAOmega double-beam spectrograph, which can be used at a range of spectral resolutions (R=lambda/delta(lambda) ~ 1700-13000) over the optical spectrum (3700-9500A). We present the first spectroscopic results obtained with SAMI for a sample of galaxies at z~0.05. We discuss the prospects of implementing hexabundles at a much higher multiplex over wider fields of view in order to carry out spatially--resolved spectroscopic surveys of 10^4 to 10^5 galaxies.