An analysis of recent measurements of the temperature of the cosmic microwave background radiation

Nobel Lecture: Cosmic microwave background radiation anisotropies: Their discovery and utilization

“…We conducted a series of campaigns in successive summers at White Mountain and then for two successive years at the South Pole which is also a high and very dry site with a very stable and relatively small atmospheric signal. We published a series of papers on the theory, observations, and interpretation leading to a much improved set of measurements at long wavelengths ͑Danese and de Zotti, 1977Zotti, , 1982Smoot et al, 1983aSmoot et al, , 1983bSmoot et al, , 1984Smoot et al, , 1987Smoot et al, , 1988Mather et al, 1994͒. The few additional observations that have tried to improve on these measurements have been generally balloon-borne versions with the same basic concept but above much more of the atmospheric signal.…”

The Cosmic Microwave Background: 25 Years Later

“…The most extensive analysis of all recent (i.e., eversince 1980) measurements of the CMB spectrum was carried out by Smoot et al (1988). These authors find that a NR Comptonized spectrum is an acceptable fit to the data.…”

“…In this case, significant distortions may arise even at low redshifts. If, however, electron heating occurred at early times and the baryon density is not too low, free-free emission may be observed at radio frequencies Stebbins and Silk, 1986), particularly around>. ::::: 40 em where the other backgrounds are low.…”

“…The upper limits set by Bernstein et al (1989) on intermediate-to-Iarge scale fluctuations of this excess sharply constrain the possibility of a local origin. On the assumption that it is real and non-local, various possible explanations have been proposed and discussed Carr, 1988;Smoot et al, 1988;Bond et ai., 1989;). …”

The temperature of the cosmic microwave background radiation at a frequency of 10 GHz

“…(The cosmological baryon density parameter fh has been taken to be O.lfor the purposes of this discussion). A more complete discussion of the CMBR spectrum and resulting cosmological implications will be published in a forthcoming paper (Smoot et al 19876).…”