Measurements of the Cosmic Microwave Background Temperature at 1.47 GHz

We have used a radio-frequency-gain total-power radiometer to measure the intensity of the cosmic microwave background (CMB) at a frequency of 1.47 GHz (20.4 cm wavelength) from White Mountain, California in 1988 September and from the South Pole, Antarctica in 1989 December. The CMB thermodynamic temperature, T_CMB_ is 2.27+/-0.25 K (68% confidence limit) measured from White MountaIn and 2.26+/-0.20 K from the South Pole site. The combined result is 2.26 +/- 0.19 K. The correction for Galactic emission has been derived from scaled low-frequency maps and constitutes the main source of error. The atmospheric signal is extrapolated from our zenith scan measurements at higher frequencies. These results are consistent with our previous measurement at 1.41 GHz (Levin et al. 1988) and ~2.5 σ from the 2.74 +/- 0.01 K global average CMB temperature.