COBE FIRAS Products
Galactic Dust Spectra and Interstellar Dust Parameters
The two dust spectrum maps (FIRAS_DUST_SPECTRUM_HIGH.FITS and FIRAS_DUST_SPECTRUM_LOWF.FITS) cover the whole sky and give the residual sky spectrum after modelled emission from the CMBR, interplanetary dust (zodiacal emission), and interstellar lines have been subtracted. The remaining signal is dominated by thermal continuum emission from Galactic interstellar dust.
Maps of the interstellar dust temperature and the 167 micron (1800 GHz) optical depth are included in the high-frequency Line Emission Map file. A single-temperature dust model was used to make these maps and the far-infrared dust emissivity was assumed to have a power law spectral index of 2.0. Different models can be used and assumptions made, and corresponding temperature and optical depth maps can be derived straightforwardly from the Dust Spectrum Maps, The continuum dust maps, and Interstelar Dust Maps .