CrossCorrelation between the 170 GHz Survey Map and the COBE Differential Microwave Radiometer FirstYear Maps
Abstract
This letter describes results of a crosscorrelation between the 170 GHz partialsky survey, made with a 3.8 deg beam balloonborne instrument, and the COBE DMR 'Fit Technique' reduced galaxy allsky map with a beam of 7 deg. The strong correlation between the data sets implies that the observed structure is consistent with thermal variations in a 2.7 K emitter. A chisquare analysis applied to the correlation function rules out the assumption that there is no structure in either of the two maps. A second test shows that if the DMR map has structure but the 170 GHz map does not, the probability of obtaining the observed correlation is small. Further analyses support the assumption that both maps have structure and that the 170 GHzDMR crosscorrelation is consistent with the analogous DMR correlation function. Maps containing various combinations of noise and HarrisonZel'dovich power spectra are simulated and correlated to reinforce the result. The correlation provides compelling evidence that both instruments have observed fluctuations consistent with anisotropies in the cosmic microwave background.
 Publication:

The Astrophysical Journal
 Pub Date:
 June 1993
 DOI:
 10.1086/186879
 Bibcode:
 1993ApJ...410L..57G
 Keywords:

 Cosmic Background Explorer Satellite;
 Cross Correlation;
 Microwave Radiometers;
 Relic Radiation;
 Satellite Observation;
 Sky Surveys (Astronomy);
 Astrophysics;
 COSMOLOGY: COSMIC MICROWAVE BACKGROUND