QUaD, an acronym for QUEST at DASI, is a ground based cosmic microwave backrground (CMB

CMB

CMB can mean:*The IATA airport code for Bandaranaike International Airport, Colombo – Sri Lanka's only international airport*C.M.B., the debut album of American R&B and pop group Color Me Badd...

) polarization experiment located at the South Pole

South Pole

The South Pole, also known as the Geographic South Pole or Terrestrial South Pole, is one of the two points where the Earth's axis of rotation intersects its surface. It is the southernmost point on the surface of the Earth and lies on the opposite side of the Earth from the North Pole...

. QUEST (Q and U Extragalactic Sub-mm Telescope) was the original name attributed to the bolometer

Bolometer

A bolometer is a device for measuring the power of incident electromagnetic radiation via the heating of a material with a temperature-dependent electrical resistance. It was invented in 1878 by the American astronomer Samuel Pierpont Langley...

 detector instrument, while DASI

Degree Angular Scale Interferometer

The Degree Angular Scale Interferometer was a telescope located in Antarctica. It was a 13-element interferometer operating between 26 and 36 GHz in ten bands. The instrument is similar in design to the Cosmic Background Imager and the Very Small Array...

 is a famous CMB interferometry

Interferometry

Interferometry refers to a family of techniques in which electromagnetic waves are superimposed in order to extract information about the waves. An instrument used to interfere waves is called an interferometer. Interferometry is an important investigative technique in the fields of astronomy,...

 experiment credited with the first detection of CMB polarization. QUaD uses the existing DASI mechanical infrastructure but replaces the DASI interferometric array with a bolometer detector at the end of a cassegrain

Cassegrain reflector

The Cassegrain reflector is a combination of a primary concave mirror and a secondary convex mirror, often used in optical telescopes and radio antennas....

 optical system.

See also

• Cosmic microwave background radiation
  Cosmic microwave background radiation
  In cosmology, cosmic microwave background radiation is thermal radiation filling the observable universe almost uniformly....
  
  
• Cosmic microwave background experiments
  Cosmic microwave background experiments
  There have been a variety of experiments to measure the Cosmic microwave background radiation anisotropies and polarization since its first observation in 1964 by Penzias and Wilson. These include a mix of ground-, balloon- and space-based receivers...
  
  

External links

• http://www.stanford.edu/~schurch/quad.html
• http://find.uchicago.edu/quad/