Overview of the SAMI Survey
SAMI is the Sydney Australian Astronomical Observatory Multi-object Integral Field Spectrograph, a brand new instrument on the 4-meter Anglo-Australian Telescope at Siding Spring Observatory. Integral field spectroscopy (IFS) allows a unique view of how stars and gas zoom around inside distant galaxies because we collect dozens of spectra across the entire face of each galaxy.
The first version of SAMI was constructed and collecting photons within 9 months of inception. University of Sydney Research Fellow Lisa Fogarty published the first science with the initial SAMI spectra.
The above images show the coverage of the SAMI fiber bundle on a galaxy. The central image shows velocities of Hydrogen-alpha measured in each individual SAMI optical fiber. The image on the right shows the final measured velocities, smoothed from different pointings across the galaxy.
A thorough instrument upgrade to SAMI2 was successfully commissioned in February 2013 thanks to the efforts of the instrument and science teams and the support of staff at the newly-reopened Siding Spring Observatory.
This photo shows PhD student Samuel Richards with the original version of SAMI (right) and the upgraded SAMI2 (left).
The SAMI Galaxy Survey began in March 2013, with the intention of creating a large survey of 3000 galaxies across a large range of environment.
The key science goals of the SAMI Survey are to answer the following questions:
- what is the physical role of environment in galaxy evolution?
- What is the relationship between stellar mass growth and angular momentum development in galaxies?
- How does gas get into and out of galaxies, and how does this drive star formation?
The images below show another galaxy example, including the Hydrogen-alpha flux, velocity, and sigma.