Compton-y Map from Planck HFI Data (v1)
We provide a map of the Compton-y parameter over roughly one-quarter
of the sky, constructed using data from the nominal mission maps
of the Planck High-Frequency Instrument.
The methodology is described in Hill & Spergel (2014).
Brief notes (see the paper for full details):
The Internal Linear Combination (ILC) techniques used to make the map explicitly remove contamination from the CMB and preserve the thermal SZ signal. Amongst the various other sources of contamination, the ILC is primarily focused on removing contamination due to extragalactic dust emission from the Cosmic Infrared Background, which is the largest contaminant to our CMB lensing cross-correlation measurement. Galactic dust emission and some level of emission from unresolved radio and infrared sources will also be present in this map (note that the associated mask covers essentially all resolved Planck sources). Keeping these caveats in mind, we anticipate that this map could be useful for additional cross-correlation studies, as long as potential contamination and leakage issues are carefully treated. Thus, we make the Compton-y map and its associated mask available here in HEALPix format (these are FITS files at HEALPix resolution Nside=2048) under the condition that you cite the above paper when using the map in any scientific analyses.
y-map mask (unapodized)
contact: jch at ias dot edu
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