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- List_of_cosmic_microwave_background_experiments abstract "There have been a variety of experiments to measure the Cosmic microwave background (CMB) 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. The most notable of these are COBE, which first detected the temperature anisotropies of the CMB, and showed that it had a black body spectrum; DASI, which first detected the polarization signal from the CMB; CBI that made high-resolution observations and obtained the first E-mode polarization spectrum, WMAP, and the Planck spacecraft, which has produced the highest resolution all-sky map to-date of both the temperature anisotropies and polarization signals, as well as various ground-based experiments primarily intended to investigate small-scale anisotropies and trying to detect the polarization caused by gravitational waves in the early universe.The design of cosmic microwave background experiments is a very challenging task. The greatest problems are the receivers, the telescope optics and the atmosphere. Many improved microwave amplifier technologies have been designed for microwave background applications. Some technologies used are HEMT, MMIC, SIS and bolometers. Experiments generally use elaborate cryogenic systems to keep the amplifiers cool. Often, experiments are interferometers which only measure the spatial fluctuations in signals on the sky, and are insensitive to the average 2.7 K background.Another problem is the 1/f noise intrinsic to all detectors. Usually the experimental scan strategy is designed to minimize the effect of such noise. To minimize side lobes, microwave optics usually utilize elaborate lenses and feed horns. Finally, the atmosphere is an issue because water absorbs microwave radiation (a fact utilized in the operation of microwave ovens), it is rather difficult to observe the microwave background with ground-based instruments. CMB research therefore makes increasing use of air and space-borne experiments. Ground-based observations are usually made from dry, high altitude locations such as the Chilean Andes and the South Pole.The list below consists of a partial list of past, current and planned CMB experiments. The name, start and end years of each experiment are given, followed by the basis of the experiment—whether space, balloon or ground based—and the location where appropriate. The frequency and amplifier technologies used are given, as is the main targets of the experiments.".
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- List_of_cosmic_microwave_background_experiments subject Category:Cosmic_microwave_background_experiments.
- List_of_cosmic_microwave_background_experiments comment "There have been a variety of experiments to measure the Cosmic microwave background (CMB) 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.".
- List_of_cosmic_microwave_background_experiments label "List of cosmic microwave background experiments".
- List_of_cosmic_microwave_background_experiments label "Lista degli esperimenti della radiazione cosmica di fondo".
- List_of_cosmic_microwave_background_experiments sameAs Lista_degli_esperimenti_della_radiazione_cosmica_di_fondo.
- List_of_cosmic_microwave_background_experiments sameAs Q3391224.
- List_of_cosmic_microwave_background_experiments sameAs Q3391224.
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