Degree Angular Scale Interferometer
The Degree Angular Scale Interferometer (DASI) was a telescope installed at the U.S. National Science Foundation's Amundsen–Scott South Pole Station in Antarctica. It was a 13-element interferometer operating between 26 and 36 GHz (Ka band) in ten bands. The instrument is similar in design to the Cosmic Background Imager (CBI) and the Very Small Array (VSA). In 2001 The DASI team announced the most detailed measurements of the temperature, or power spectrum of the cosmic microwave background (CMB). These results contained the first detection of the 2nd and 3rd acoustic peaks in the CMB, which were important evidence for inflation theory. This announcement was done in conjunction with the BOOMERanG and MAXIMA experiment. In 2002 the team reported the first detection of polarization anisotropies in the CMB.
| Part of | Amundsen–Scott South Pole Station |
|---|---|
| Location(s) | South Pole, Antarctic Treaty area |
| Coordinates | 89°59′29″S 44°30′00″W |
| Organization | Centre for Astrophysical Research in Antarctica National Science Foundation University of Chicago |
| Altitude | 2,800 m (9,200 ft) |
| Wavelength | 0.83 cm (36 GHz)–1.2 cm (25 GHz) |
| Built | 1999–2000 |
| Telescope style | cosmic microwave background experiment radio interferometer |
| Number of telescopes | 13 |
| Diameter | 20 cm (7.9 in) |
| Website | astro |
Location of Degree Angular Scale Interferometer | |
In 2005, the vacant DASI mount was used for the QUaD experiment, which was another CMB imager focussed on the E-mode spectrum. In 2010, the DASI mount was again repurposed for the Keck Array, which also measures CMB polarization anisotropy.