QUaD is a bolometric array receiver that is being used to search for polarization
in the CMB. The spatial distribution of polarization contains important information about cosmological parameters and about the origin of temperature anisotropies in the CMB. Although the signal is tiny (1-10% of the temperature fluctuations) the scientific rewards are large. A measurement of polarization has the potential to distinguish between inflationary models by measuring the amount of primordial gravitational waves that are a relic of the inflationary epoch.
QUaD has completed its observations and new results are now available.