Session B14 - Galaxies, Supernovae, and Cosmology.
ORAL session, Saturday morning, April 28
Room 14, Renaissance Hotel$
The Diffuse Infrared Background Experiment (DIRBE) flew on the Cosmic Background Explorer (COBE) in 1989--90 and executed a full--sky survey in 10 bands from 1.2 to 240 \mum. The DIRBE data were used to construct a model of the signal from the interplanetary dust cloud so that it could be removed from the data as a first step in determining the faint IR signal from the cosmic infrared background (CIRB). An analysis of the results after removing the model disclosed that the Zodiacal IR signal is variable and is correlated with solar variations. The variations show wavelength--dependent periodicities, have amplitudes at levels of the estimated CIRB for most of the bands, and are spatially nonuniform. The nature of this discovery and its consequences in determining the CIRB will be discussed.