Lensing reconstructions 02.00

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J.Carron 27 Sept. 2018

This page documents the 600 lensing maps (healpy alm fits files, lmax=3000) available at


There are 6 type of maps, labeled with

  • sim_ptt_????_lmax3000.fits

lensing map from temperature only, simulation index ???? 0000 to 0099

  • sim_p_p_????_lmax3000.fits

lensing map from polarization only

  • sim_p_????_lmax3000.fits

lensing map from temperature and polarization (MV)

  • sim_xtt_????_lmax3000.fits

lensing curl map from temperature, useful for null tests

  • sim_x_p_????_lmax3000.fits

lensing curl map from polarization

  • sim_x_????_lmax3000.fits

lensing curl from temperature and polarization (MV)

The maps were built using the quadratic estimator implementation described in the 2018 CMB lensing paper, with the exception of the filtering, which is isotropic after application of a slightly apodized mask.

For illustration, the temperature (TT), polarization (PP) and Minimum Variance (MV) Wiener-filtered displacement reconstructions, together with the input, for realization 99:

Recmaps cmbs4 apo.png

Reconstruction parameters

  • CMB multipoles from 200 to 3000
  • Analysis mask: fmask.fits in same folder
  • Gaussian beam of 4 arcmin FWHM
  • Flat noise of 1.5 and 2.12 muK-arcmin
  • FFP10 fiducial lensing spectra
  • Separate temperature and polarization filtering

Fidelity to the input

The cross-correlation correlation to the input maps, as calculated across the entire patch is like this:



The mean-field (here, contribution from the mask and noise anisotropies) has not been subtracted out from the maps on disk. The mean-field spectra look like this:

MF cmbs4.png

The mean-field subtraction can be performed subtracting the lensing reconstructed maps averaged over a subset of the simulations.