Determination of the Cosmic Infrared Background from COBE/FIRAS and Planck HFI Observations

Understand

New determinations are presented of the cosmic infrared background monopole brightness in the Planck HFI bands from 100 GHz to 857 GHz.

• Planck was not designed to measure the monopole component of sky brightness, so cross-correlation of the 2015 HFI maps with COBE/FIRAS data is used to recalibrate the zero level of the HFI maps.
• For the HFI 545 and 857 GHz maps, the brightness scale is also recalibrated.
• Correlation of the recalibrated HFI maps with a linear combination of Galactic H I and H alpha data is used to separate the Galactic foreground emission and determine the cosmic infrared background brightness in each of the HFI bands.