PR3 Legacy CMB Maps

CMB maps have been produced using four different methods: COMMANDER, NILC, SEVEM, and SMICA, as described in the CMB and foreground separation section and also in Appendices AD of Planck 2018 results L04 and references therein.For each method the Planck Collaboration has produced: Fullmission CMB intensity map, with corresponding confidence mask and effective beam transfer function. Full mission CMB polarisation map, with corresponding confidence mask and effective beam transfer function.All CMB products are provided at an approximate angular resolution of 5 arcmin FWHM, and HEALPix resolution Nside2048. Explicit effective beam profiles are provided for each foreground reduced CMB map.For a complete description of the above data structures, see below; the content of the first extensions is illustrated and commented in the table below.Four separate component separation methods are used, which we now describe in turn. Commander The Commander approach implements Bayesian component separation, fitting a parametric model to the data by sampling the corresponding posterior distribution. The computational engine in this approach is standard Gibbs sampling. The general Commander model includes both cosmological parameters (i.e., the CMB map and power spectrum), astrophysical parameters (e.g., synchrotron, freefree, spinning and thermal dust, and CO emission), and instrumental parameters (e.g., calibration factors, absolute zerolevels, and bandpass corrections). The full model was employed in the Planck 2015 analysis (Planck 2015 results X) which included both singledetector Planck maps and external observations from WMAP and Haslam. For the reduction of the Planck 2018 data set, which includes only fullfrequency maps, a simpler model is employed, in which only a single joint powerlaw low frequency foreground model is included in the fit, accounting simultaneously for synchrotron, free free and spinning dust emissi[truncated, see actual data for full text]