Atacama Cosmology Telescope

The Atacama Cosmology Telescope ACT is a radio telescope to study the cosmic microwave background ( CMB).

ACT is a 6- m telescope at an altitude of 5148 m on Cerro Toco in the Atacama Desert in northern Chile. Telescope and instrumentation are designed to examine the irregularities of the cosmic microwave background and for the discovery of galaxy clusters by Sunyaev - Zeldovich from their effect induced local change of the microwave background. Together with follow-up observations, the discovery of many clusters of galaxies to understand the structural evolution of the universe and dark energy could contribute.

A first test receiver went into operation in June 2007 and the telescope saw first light on 22 October 2007. The main instrument is a bolometer camera ( millimeter bolometer array camera, MBAC ) with novel superconducting transition edge sensor for three frequencies between 145 GHz and 280 GHz. ACT is built jointly by 17 institutions from the United States (including Princeton University ), Canada, Mexico, Chile, South Africa and the UK, operated and funded primarily by the National Science Foundation. Was built the telescope of Dynamic Structures in Vancouver.

The CMB is measured with a resolution of millionths of a degree and an angular resolution in minutes of arc area.

First results were published in 2010 and there were gravitational lens effects observed and the first indications of Dark Energy from the CMB alone.

Similar objectives of the South Pole Telescope, which also saw first light in 2007.