Measurement of CIB power spectra over large sky areas from Planck HFI
  maps
  We present new measurements of the power spectra of the cosmic infrared
background (CIB) anisotropies using the Planck 2015 full-mission HFI data at
353, 545, and 857 GHz over 20000 square degrees. We use techniques similar to
those applied for the cosmological analysis of Planck, subtracting dust
emission at the power spectrum level. Our analysis gives stable solutions for
the CIB power spectra with increasing sky coverage up to about 50% of the sky.
These spectra agree well with Hi cleaned spectra from Planck measured on much
smaller areas of sky with low Galactic dust emission. At 545 and 857 GHz our
CIB spectra agree well with those measured from Herschel data. We find that the
CIB spectra at l > 500 are well fitted by a power-law model for the clustered
CIB, with a shallow index {\gamma}^cib = 0.53\pm0.02. This is consistent with
the CIB results at 217 GHz from the cosmological parameter analysis of Planck.
We show that a linear combination of the 545 and 857 GHz Planck maps is
dominated by CIB fluctuations at multipoles l > 300.
