The Astrophysical Journal · 1984 · 63 citations · 0 references
Natural SciencesAstronomyPhysicsCosmologyObservational AstronomyRadio AstronomyCosmic Microwave BackgroundCosmic Microwave Background ObservationsExtragalactic Radio AstronomyObservational CosmologyRadio TelescopesSpace-based Gamma-ray ObservatoriesAnisotropy MeasurementsAnisotropy Of The Cosmic Microwave BackgroundBeamwidthCmb Secondary AnisotropiesCmb Temperature AnisotropiesCosmic Microwave Background AnisotropiesMaser EmissionPrimary Anisotropies
The authors have searched for small-scale anisotropy in the cosmic microwave background using the maser receiver and 140 foot telescope of the NRAO, operating at a frequency of 19.5 GHz. The half-power beamwidth was 1arcmin.5. Beam switching by 4arcmin.5 was used in order to minimize variable contributions from ground and atmospheric emission and from the instrument. The data set an upper limit of (ΔT/T)<SUB>rms</SUB> < 4.5×10<SUP>-5</SUP> at the 95% confidence level on fluctuations at the 4arcmin.5 scale.