We report on the preliminary result of a search for anisotropy in the cosmic background radiation (CBR) with a beam size of ~1.5^deg^ FWHM over a wavelength range of 8-12 mm. The system operated successfully for 500 hr at the South Pole during the 1990-1991 austral summer. The data from one region, representing 25 hr after editing, are presented here. A strong signal is present in the lower frequency channels with a spectrum unlike CBR fluctuations, and is probably due to foreground emission. The highest frequency channel has the smallest contribution from this signal and has been used to set a 95% confidence level upper limit of {DELTA}T/T<=1.4 x 10^-5^ for fluctuations with a Gaussian autocorrelation function at a coherence angle of 102. This is significantly more sensitive than previous experiments at this angular scale.
No takes yet. Share an insight, caveat, or question.
Gaier et al. (1992) studied this question.