Specially processed maps

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Overview[edit]

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[edit]

Description[edit]

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 $R_L^{\phi\phi}$. 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.
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[edit]

Description of the Pipeline used to generate the product. In particular any limitations and approximations used in the data processing should be listed. Avoiding detailed descriptions of methods and referring to other parts of the ES and/or the relevant Planck papers for the details. References however should be quite detailed (i.e. it is not enough to direct the user to a paper, but the relevant section in the paper should be provided).

Inputs[edit]

A list (and brief description to the extent possible) of the input data used to generate this product (down to file names), as well as any external ancillary data sets which were used.

Related products[edit]

A description of other products that are related and share some commonalities with the product being described here. E.g. if the description is of a generic product (e.g. frequency maps), all the products falling into that type should be listed and referenced.

File names and format[edit]

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'
PHIBAR Real*4 none Map of the lensing potential
MASK Int none Region over which the lensing potential is reconstructed
2. EXTNAME = 'TransFun'
RLPP Real*4 none Response function (see above)
NLPP Real*4 none sky-averaged noise spectrum

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 $l_{max} =2028$.

(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