The Cosmic Anisotropy Telescope

The Cosmic Anisotropy Telescope (CAT) was the first interferometer to measure fluctuations in the cosmic microwave background (CMB). Its first results, published in 1996, were the highest resultion CMB detection at that time, and showed that the rise in fluctuation power towards scales of ~1 degree (l ~ 200) measured by the Saskatoon experiment were matched by a decline in power at smaller angles (l = 500-700), thus showing the existence of the long-predicted acoustic peak in the CMB power spectrum. Further results were published in 1999. The telescope was turned off and partly dismantled in 2000.

Information about CAT

• Some details about the CAT
• Press release describing first CAT results
• O'Sullivan et al 1995 The first CAT observations.
• Scott et al 1996
The first CAT CMB power spectrum results.
• Baker et al 1999 The second CAT CMB results.

The successor telescope to the CAT is the The Very Small Array, a 14-element interferometer based in Tenerife.

Links to elsewhere

• Mullard Radio Astronomy Observatory (Cambridge, UK).
• Cambridge Astronomy (Cambridge, UK).
• The Cavendish Laboratory (Cambridge, UK).