Science Goals

EMU is a proposed radio sky survey project, designed to use the new ASKAP telescope to make a deep (~10µJy rms) radio survey covering the entire Southern Sky (perhaps as far North as 30°. It can be characterised as a “Southern NVSS”, except that it will have about 40 times the sensitivity of the NVSS. As a result, it will be able to probe typical star forming galaxies up to a redshift of 1 (i.e. looking back in time to about half the age of the Universe) and the most extreme starbursts to even greater redshifts. Quasars and galaxies hosting massive black holes will be seen right out near the edge of the observable Universe, where the first massive black holes were born. Perhaps even more importantly, EMU will almost certainly uncover new classes of object.

The project was one of 39 competing to use ASKAP. Expressions of Interest were solicited in November 2008, and selected proposals (including EMU) invited to submit a full proposal by 15 June 2009. EMU was ranked equal top (with WALLABY) of the projects, and so has been invited to play a significant role in ensuring that ASKAP is built and operated to maximise the science return. Potential participants are invited to join the team, and will then have the opportunity to participate in designing the parameters and processes of the survey, and the commissioning and quality control.

All radio data from the survey will be placed in the public domain as soon the data quality has been checked. An integral part of the proposed project will be to identify sources with other wavelengths, and produce public-domain VO-accessible catalogs of these and other “added-value” data products.

The  EMU survey will cover almost as much area as NVSS, but will be a factor of 40 times more sensitive. 

The key science goals for EMU include:

• To trace the evolution of star-forming galaxies from z=2 to the present day, using a wavelength unbiased by dust or molecular emission.
• To trace the evolution of massive black holes throughout the history of the Universe, and understand their relationship to star-formation.
• To use the distribution of radio sources to explore the large-scale structure and cosmological parameters of the Universe.
• To explore an uncharted region of observational parameter space, almost certainly finding new classes of object.
• To create the most sensitive wide-field atlas of Galactic continuum emission yet made in the Southern Hemisphere, addressing areas such as star formation, supernovae, and Galactic structure.
• To discover the unexpected.

For more information:

• EMU Survey Definition Paper
• Astronomers wiki pages