A&A special issue: Planck 2015 results
Astronomy & Astrophysics, 2016, 594, October 2016
Table of contents of the A&A special feature
Astronomy & Astrophysics is publishing a special issue of 28 articles to describe the latest release of data gathered by the European Space Agency's Planck satellite, which took place between February and August 2015. This series of papers presents the data products released and the scientific results extracted from them by the Planck Collaboration.
Planck is ESA's mission to observe the cosmic microwave background (CMB) - the first light in the Universe. Planck was designed to image the temperature and polarization anisotropies of the CMB over the whole sky, with unprecedented sensitivity and angular resolution. The Planck data is used to test theories of the early universe and the origin of cosmic structure and provides a major source of information relevant to many cosmological and astrophysical issues.
Planck was launched on 14 May 2009, and the minimum requirement for success was that the spacecraft should complete two whole surveys of the sky. In the end, Planck operated continuously for ~50 months. It completed five full-sky surveys with both Low and High Frequency instruments (LFI and HFI), and more than eight full-sky surveys with the LFI. Planck eventually stopped acquiring data in October 2013.
The early release of the Planck data in 2011 included cluster and point source catalogs. The first public release of Planck data took place in March 2013. It included maps of the temperature anisotropies of the CMB, built from data gathered by Planck over its initial 15 months of operations. This release was described in an A&A special issue published in November 2014 (volume 571).
The most recent 2015 data release is much more extensive than the previous one: it uses the complete Planck dataset to build maps of both temperature and polarization anisotropies of the CMB covering the entire sky. The all-sky polarization maps at high frequencies offer a completely new view of the sky, and the entire set constitutes a very important new scientific tool for both cosmology and astrophysics.
The polarization maps allow us to estimate cosmological parameters independently of temperature data - the degree of consistency of these two lines of analysis is very good, giving high confidence in the Planck data's reliabiitey. The bst >Planck15 dataological parameters indeidencrem by ''ic strunt ipe''t the descri">Deiny Planck over011 in3MB)see4 (2con59>A&ass-releases" >nck-2015-re3ults" /> >s-rel ase ).embpletete, ighevce in thed" (C bothcosmnsive t= est modelarchthcosmneo testirementmnsoes/ ics.
The ophysics articlso ofaof tbenefinit them by>Planck dataset e bsteviization maps at high frequencies offeted e cosmed bmaraeion to ooperd2015pcles to dh tookhbackg Feicld to ihe Pl ificees/ fieapsturmfao ige LFI.MilolaWayis relen in scie for both (C in nedthe en ics artic(CMBene="_bartihe sky,Galve">cernatisite,esoa/syum>
The polars presuded mapshe