An international consortium representing more than 15 countries, including sites in Europe, the US, Australia, Canada, China, India and South Africa, is building the SKA, to be online in ~2012. This telescope will provide two orders of magnitude increase in sensitivity over existing facilities. To achieve this goal will require a telescope with one square kilometer of collecting area one hundred times more collecting area than the Very Large Array (VLA).
The SKA will probe the gaseous component of the early universe, addressing fundamental questions on the origin and evolution of the universe. The SKA will complement planned facilities at other wavelengths, such as the ALMA and James Webb Space Telescope (JWST). HI, CO and continuum radiation would be observed from the interstellar medium of most of the galaxies the JWST will discover in the infrared at large redshifts.
The SKA will be an interferometric array of individual antenna stations, synthesizing an aperture with a diameter of up to several 1000 kilometers. A number of configurations are under consideration to distribute the 1 million square meters of collecting area. These include 30 stations each with the collecting area equivalent to a 200-meter diameter telescope, and 150 stations each with the collecting area of a 90-meter telescope.
Following proposals for and the analysis of potential locations, and the advice of the International SKA Site Advisory Committee, the International SKA Steering Committee (ISSC) decided that the short-list of acceptable sites are Australia and Southern Africa. Additional studies of the characteristics of the short-listed sites will be carried out in 2007 and 2008. A final decision of the location of the SKA is expected thereafter.
Numerical Simulations to Optimize the SKA Design
www.isgtw.org/?pid=1000976
Towards the end of these Dark Ages, the Universe entered a new phase the Epoch of Reionization when UV and X-ray emissions from stars and quasars began to reionize the newly formed neutral atoms.
We have very few ways to gather observational information about the epoch of reionization, because the photons emitted by stars and quasars are absorbed by the intergalactic medium before they reach us, explained Benoit Semelin, an astrophysicist at the Paris Observatory in France. But, there is one kind of radiation to which the universe is transparent, even during the epoch of reionization: the 21-cm emission of neutral hydrogen. To detect these emissions, the world is building the international SKA radio telescope.
To optimize the design of this instrument we need to have the best possible models of the 21-cm emission, says Semelin. This is achieved by numerical simulations. Semelin and his team are using their grid-enabled LICORICE code to run Monte Carlo simulations of the radiative transfer of photons, including up to 109 virtual photons per simulation. These simulations are scheduled to run on EGEE grid.
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Collaborators:
Argentina:
SKA
Australia:
Consortium (Australian Square Kilometre Consortium; CSIRO Australia Telescope National Facility; University of Sydney; Swinburne SKA Simulation and Radio Interferometry Group)
Canada:
National Research Council of Canada
China:
Five-hundred-metre Aperture Spherical Telescope (FAST)
Europe:
SKA Design Studies on Aperture Array Tiles (SKADS)
Italy:
ASTRON
New Zealand:
Centre for Radiophysics and Space Research
India:
SKA Indian Consortium (SKAIC)
South Africa:
SKA; South Africa
USA:
US SKA Consortium
