Specially processed maps

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Lensing map[edit]


Here we present the minimum-variance (MV) lens reconstruction which forms the basis for the main results of #planck2013-p12. This map is produced using a combination of the 143 and 217 GHz Planck maps on approximately 70% of the sky, and is the same map on which the Planck lensing likelihood is based.

We distribute:

A (transfer-function convolved) map of the lensing potential, in NSIDE 2048 HEALPix RING format. It is obtained by convolving the lensing potential estimate $\hat{\phi}$ with the lensing response function $R_L^{\phi\phi}$. This map has been band-limited between multipoles $10 \le L \le 2048$.
This is a NSIDE = 2048 HEALPix map, containing the analysis mask used in the lens reconstruction. Note: the lensing map PHIBAR may take small but non-zero values inside the masked regions because it has been bandlimited.
This column contains the response function $R_L^{\phi\phi}$.
This column contains a sky-averaged estimate of the noise power spectrum of PHIBAR, $N_L^{\phi\phi}$. The noise is highly coloured. There is a weak dependence of the noise power spectrum with the local noise level of the map, discussed in Appendix A of #planck2013-p12. Note that the noise power spectrum estimate here is not sufficiently accurate for a power spectrum analysis.

Production process[edit]

The construction PHIBAR, RLPP and NLPP are described in detail in Sec. 2.1 of #planck2013-p12. The response function $R_L^{\phi\phi}$ here is analogous to the the beam transfer function in a CMB temperature or polarization map. We have chosen to distribute this transfer-function convolved map rather than the normalized lens reconstruction as it is a significantly more localized function of the CMB temperature map from which it is derived, and therefore more useful for cross-correlation studies.


This product is built from the 143 and 217 GHz Planck sky maps.


<biblio force=false>

  1. References


File names and format[edit]

A single file named

  • COM_CompMap_Lensing_2048_R1.10.fits

with two BINTABLE extensions containing the items described below.

FITS file structure
Column Name Data Type Units Description
PHIBAR Real*4 none Map of the lensing potential estimate, convolved with RLPP
MASK Int none Region over which the lensing potential is reconstructed
Keyword Data Type Value Description
COORDSYS string GALACTIC Coordinate system
ORDERING string NESTED Healpix ordering
NSIDE Int*4 2048 Healpix Nside
LASTPIX Int*4 50331647
2. EXTNAME = TransFun
Column Name Data Type Units Description
RLPP Real*4 none Response function
NLPP Real*4 none Sky-averaged noise power spectrum estimate
Keyword Data Type Value Description
L_MIN Int*4 0 First multipole
L_MAX Int*4 2048 Last multipole

(Hierarchical Equal Area isoLatitude Pixelation of a sphere, <ref name="Template:Gorski2005">HEALPix: A Framework for High-Resolution Discretization and Fast Analysis of Data Distributed on the Sphere, K. M. Górski, E. Hivon, A. J. Banday, B. D. Wandelt, F. K. Hansen, M. Reinecke, M. Bartelmann, ApJ, 622, 759-771, (2005).

Cosmic Microwave background

Flexible Image Transfer Specification