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KAT - XDM First Light 2007/07/16


The eXperimental Development Model (XDM) is a 15-m diameter radio telescope antenna of novel design intended to reduce antenna construction cost per square metre and bring it close to that needed to make Square Kilometre Array (SKA) affordable. IST Holdings are the prime contractors building XDM at Hartebeesthoek.

The Karoo Array Telescope (KAT) will be used to test technology leading up to development of the Square Kilometer Array (SKA). The XDM is a testbed prototype for KAT.

xdm first light celebration
Click on image for LARGE version

The XDM was built between 2007 January and June 2007. Simple, single-polarization test receivers constructed by HartRAO were installed to verify the radio performance of the telescope in 2007 July. The 1.5GHz / 18cm wavelength receiver saw first light on the telescope on July 16. This is the design operating band for XDM. Two days later, after intensive testing, it was replaced by a 12GHz / 2.5cm wavelength receiver to measure the potential performance in a band well above the design band.

The image above shows the July 19 celebration of first light by testers from the KAT team, IST, HartRAO, Tellumat who are building the next receiver system, and visiting Jodrell Bank engineer Neil Roddis.

For a pictorial review of the construction and testing of XDM at HartRAO, see the XDM webpages.

Key contacts for XDM / KAT / SA-SKA: