Specially processed maps

Overview

A general description of the product, including e.g. figures related to the contents (e.g. maps, tables), and some explanation of its scientific meaning. If there are scientific warnings about the use of the product (User’s caveats), they should also be given here, or at least references to other explanatory documents (papers etc).

Lensing map

Description

The fiducial Planck lensing potential map is made from a minimum variance combination of the 143 and 217 GHz Planck maps on approximately 70% of the sky, using 857GHz as a dust template. This is the same lens reconstruction on which the Planck lensing likelihood is based.

We distribute:

PHIBAR 

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 $R_L^{\phi\phi}$.

MASK 

This is a NSIDE 2048 HEALPix map, containing the analysis mask used in the lens reconstruction.

RLPP 

This column contains the response function $R_L^{\phi\phi}$.

NLPP 

This column contains a sky-averaged estimate of the noise power spectrum of PHIBAR. The noise is highly coloured. Note that there is some dependence of the noise power spectrum with the local noise level of the map. Note that the noise power spectrum estimate here is not sufficiently accurate for a power spectrum analysis.

[From Duncan Hanson, Feb.2013]

Production process

The construction of these quantities are described in detail in Sec. 2.1 of P12_Lensing. This map has been band-limited between multipoles $10 \le L \le 2048$. 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. This is discussed further in Appendix A of P12_Lensing.

Inputs

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

File names and format

A single file named COM_CompMap_Lensing_2048_R1.10.fits with two BINTABLE extensions containing the items described above.

Column Name	Data Type	Units	Description
1. EXTNAME = 'LENS-MAP' : Data columns
PHIBAR	Real*4	none	Map of the lensing potential
MASK	Int	none	Region over which the lensing potential is reconstructed
Keywords
PIXTYPE	HEALPIX
COORDSYS	GALACTIC	Coordinate system
ORDERING	NESTED	Healpix ordering
NSIDE	2048	Healpix Nside
FIRSTPIX	0
LASTPIX	50331647
2. EXTNAME = 'TransFun' : Data columns
RLPP	Real*4	none	Response function (see above)
NLPP	Real*4	none	sky-averaged noise spectrum
Keywords
L_MIN	0
L_MAX	2048

The maps in Ext 1 are, as usual, in GALACTIC coordinates, Nside=2048 and in NESTED ordering. The vectors in Ext 2 run from $l_{min} = 0$ to $l_{max} =2028$.