Noise Equivalent Power of Background Limited Thermal Detectors at Submillimeter Wavelengths

With the advent of large submillimeter telescopes at high, dry sites, the atmospheric background noise in a moderate bandwidth can be low enough to challenge the ability of instrument designers to produce su ciently low noise bolometers to be background limited. We compare the predictions for the noise power of a bolometer observing through an emissive atmosphere, considering the e ect of atmospheric absorption, telescope optical e ciency, and detector optical e ciency, with measurements through the atmosphere over Mauna Kea.