page_title: QUaD
hierarchical_section_title: QUaD
caption_attribution_description: A photograph of the en:QUaD telescope inside its groundshield taken from a crane above the telescope. The telescope structure consists of a en:cassegrain optical system mated to the existing DASI mount surrounded by a reflective groundshield which limits signal contamination by the warm ~200K ground below. The secondary mirror is suspended by a large white foam cone, which is transparent to microwave frequency radiation.
context_page_description: QUaD, an acronym for QUEST at DASI, was a ground-based cosmic microwave background polarization experiment at the South Pole. QUEST was the original name attributed to the bolometer detector instrument, while DASI is a famous CMB interferometry experiment credited with the first detection of CMB polarization. QUaD used the existing DASI mechanical infrastructure but replaced the DASI interferometric array with a bolometer detector at the end of a cassegrain optical system. The mount has housed the Keck Array since 2011.
context_section_description: QUaD, an acronym for QUEST at DASI, was a ground-based cosmic microwave background (CMB) polarization experiment at the South Pole. QUEST (Q and U Extragalactic Sub-mm Telescope) was the original name attributed to the bolometer detector instrument, while DASI is a famous CMB interferometry experiment credited with the first detection of CMB polarization. QUaD used the existing DASI mechanical infrastructure but replaced the DASI interferometric array with a bolometer detector at the end of a cassegrain optical system. The mount has housed the Keck Array since 2011.
caption: A photograph of the QUaD telescope inside its groundshield taken from a crane above the telescope.
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