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SRoll 2.0 data release



Data set description

The SRoll 2.0 data set is made of 28 FITS files each containing the I, Q and U Stokes parameters of a single frequency, multi-bolometer, full-sky observation in KCMB, as well as its hit count and covariance matrix elements (II, IQ, IU, QQ, QU, UU, in KCMB2). These maps are generated using only the 8 polarised HFI bolometers ("PSB") of each polarised HFI frequency (100 GHz, 143 GHz, 217 GHz and 353 GHz) to obtain the best possible polarised maps. The maps are stored in HEALPix format at Nside=2,048 (50,331,648 pixels per map). They are named and formatted in the same way as the Planck HFI 2018 products (see the Planck Legacy Archive (PLA)):



Click on a filename to download it


filenameunset pixels (1)total hit count (2)monopole [KCMB] (3)
SRoll20_SkyMap_100psb_full.fits 1 73,610,049,461 1.084146e-04
SRoll20_SkyMap_100psb_halfmission-1.fits 2,528 35,159,616,608 1.084146e-04
SRoll20_SkyMap_100psb_halfmission-2.fits 50,976 38,445,797,009 1.084147e-04
SRoll20_SkyMap_100psb_full-oddring.fits 245,997 36,813,155,142 1.084146e-04
SRoll20_SkyMap_100psb_full-evenring.fits 250,726 36,763,865,185 1.084151e-04
SRoll20_SkyMap_100ds1_full.fits 506 37,361,828,313 1.084146e-04
SRoll20_SkyMap_100ds2_full.fits 14 36,248,157,754 1.084146e-04
SRoll20_SkyMap_143psb_full.fits 0 68,843,796,891 1.572528e-04
SRoll20_SkyMap_143psb_halfmission-1.fits 7,163 32,872,886,255 1.572528e-04
SRoll20_SkyMap_143psb_halfmission-2.fits 67,297 35,966,598,664 1.572539e-04
SRoll20_SkyMap_143psb_full-oddring.fits 6,360 34,365,731,398 1.572529e-04
SRoll20_SkyMap_143psb_full-evenring.fits 4,866 34,476,945,981 1.572529e-04
SRoll20_SkyMap_143ds1_full.fits 8,963 34,020,139,934 1.572528e-04
SRoll20_SkyMap_143ds2_full.fits 1 34,822,520,382 1.572528e-04
SRoll20_SkyMap_217psb_full.fits 1 66,504,719,750 5.400523e-04
SRoll20_SkyMap_217psb_halfmission-1.fits 13,618 31,516,161,239 5.400523e-04
SRoll20_SkyMap_217psb_halfmission-2.fits 116,377 34,980,457,031 5.400522e-04
SRoll20_SkyMap_217psb_full-oddring.fits 23,361 33,123,866,721 5.400523e-04
SRoll20_SkyMap_217psb_full-evenring.fits 20,931 33,377,208,031 5.400525e-04
SRoll20_SkyMap_217ds1_full.fits 9,716 33,394,633,451 5.400523e-04
SRoll20_SkyMap_217ds2_full.fits 21,624 33,107,556,356 5.400525e-04
SRoll20_SkyMap_353psb_full.fits 0 67,059,476,595 3.783446e-03
SRoll20_SkyMap_353psb_halfmission-1.fits 1,403 31,840,611,619 3.783446e-03
SRoll20_SkyMap_353psb_halfmission-2.fits 39,832 35,216,695,886 3.783447e-03
SRoll20_SkyMap_353psb_full-oddring.fits 3,102 33,480,025,683 3.783446e-03
SRoll20_SkyMap_353psb_full-evenring.fits 2,483 33,578,820,901 3.783446e-03
SRoll20_SkyMap_353ds1_full.fits 5,029 33,521,826,342 3.783446e-03
SRoll20_SkyMap_353ds2_full.fits 1 33,536,882,370 3.783446e-03


1. unset pixels are pixels either not seen by any bolometer of the detector set, or with an ill-conditioned covariance matrix due to the insufficient detector polarisation orientation distribution related to the Planck pointing. Unset pixels in SRoll 2.0 maps are set to HEALPix UNSEEN value (-1.6375e+30) in I_STOKES, Q_STOKES and U_STOKES maps, and to 0.0 in the covariance matrix elements (II, IQ, IU, QQ, QU, UU). Pixels with ill-conditioned covariance matrix still have a valid hit count in the HIT map.


2. total hit count is the the sum of HIT map valid pixel values. In Python, this is:



3. monopoles of the intensity maps are set to the same values as in Planck Legacy HFI2018 maps with the same frequency. The values given in the table are the results of the fit_monopole() function of the HEALPix library.


The dipole removed from the SRoll 2.0 intensity maps is the same one as for Planck Legacy Release:

Amplitude: 3362.08 microK
Galactic Longitude: 264.021 deg.
Galactic Latitude: 48.253 deg.



Data file format description

The SRoll 2.0 data files use the same FITS file format as the Planck Legacy Archive (PLA). More details can be found in the FITS file format description page.