2019/08/31 by L. Pagano, J. -M. Delouis, S. Mottet +2 · 2 citations
Physics and Astronomy · #astro-ph.CO
paper · pdf · doi:10.1051/0004-6361/201936630
published as A&A 635, A99 (2020) · 11 pages, 18 figures; matches published version. Maps and simulations available at http://sroll20.ias.u-psud.fr, likelihood at https://web.fe.infn.it/~pagano/low_ell_datasets/sroll2
arxiv created 2020/05/26 · arxiv updated 2020/05/27
We present an estimation of the reionization optical depth τ from an improved analysis of the High Frequency Instrument (HFI) data of Planck satellite. By using an improved version of the HFI map-making code, we greatly reduce the residual large scale contamination affecting the data, characterized, but not fully removed, in the Planck 2018 legacy release. This brings the dipole distortion systematic effect, contaminating the very low multipoles, below the noise level. On large scale polarization only data, we measure τ=0.0566-0.0062+0.0053 at 68% C.L., reducing the Planck 2018 legacy release uncertainty by ∼40%. Within the ΛCDM model, in combination with the Planck large scale temperature likelihood, and the high-ℓ temperature and polarization likelihood, we measure τ=0.059±0.006 at 68% C.L. which corresponds to a mid-point reionization redshift of z\rm re=8.14±0.61 at 68% C.L.. This estimation of the reionization optical depth with 10% accuracy is the strongest constraint to date.