Measurements of the Cosmic Background Radiation

Abstract

Maps of the large scale structure (θ>6 °) of the cosmic background radiation covering 90% of the sky are now available. The data show a very strong 50–100 σ (statistical error) dipole component, interpreted as being due to our motion, with a direction of α = 11.25 ± 0.15 hours, δ = -5.6 ± 2.0° The inferred direction of the velocity of our galaxy relative to the cosmic background radiation is α = 10.6 ± 0.3 hours, δ = -23 ± 5° (l ^II = 267 °, b ^II = 31 °). This is 44° from the center of the Virgo cluster. After removing the dipole component the data show a Galactic signature but no apparent residual structure. An autocorrelation of the residual data, after subtraction of the Galactic component from a combined Berkeley (3 mm) and Princeton (12 mm) data set, shows no apparent structure from 10° to 180° with a rms of 0.01 mK². A 90% confidence level limit of 7x 10^-5 is placed on a quadrupole component.