Large-scale anisotropy at centimeter wavelengths

Abstract

Intrinsic effects in the case of large-scale anisotropy measurements could possibly provide much information about the early universe. Techniques for experimental investigations at centimeter wavelengths are discussed, taking into account the basic problem to measure the difference in the radiation temperature form two directions in the sky with an accuracy of better than 0.0001 K. The largest anisotropy in the 2.7 K background radiation is a dipole distribution, most of which is due to the sun's velocity with respect to the radiation frame. It is pointed out that two very recent results how good agreement with older dipole data. A cooled 3 mm mixer radiometer and a 1.2 cm maser radiometer were flown in balloon. The results of a search for evidence of a quadrupole distribution in the 2.7 K radiation are also reported.