Improved constraints on reionisation from CMB observations: a parameterisation of the kSZ effect

0545146 - FZÚ 2022 RIV FR eng J - Journal Article
Gorce, A. - Ilić, Stephane - Douspis, M. - Aubert, D. - Langer, M.
Improved constraints on reionisation from CMB observations: a parameterisation of the kSZ effect.
Astronomy & Astrophysics. Roč. 640, Aug (2020), č. článku A90. ISSN 0004-6361. E-ISSN 1432-0746
R&D Projects: GA MŠMT EF15_003/0000437
Grant - others:OP VVV - CoGraDS(XE) CZ.02.1.01/0.0/0.0/15_003/0000437
Institutional support: RVO:68378271
Keywords : methods: analytical * cosmic background radiation * dark ages * reionization * first stars
OECD category: Particles and field physics
Impact factor: 5.803, year: 2020
Method of publishing: Open access

We show that, in the context of patchy reionisation, an accurate description of the angular power spectrum of the kinetic Sunyaev–Zel’dovich (kSZ) effect is not possible with simple scaling relations between the amplitude of the spectrum and global parameters, such as the reionisation midpoint and its duration. We introduce a new parameterisation of this spectrum, based on a novel description of the power spectrum of the free electrons density contrast Pee(k, z) in terms of the reionisation global history and morphology. We directly relate features of the spectrum to the typical ionised bubble size at different stages in the process and, subsequently, to the angular scale at which the patchy kSZ power spectrum reaches its maximum. We successfully calibrated our results on a custom set of advanced radiative hydrodynamical simulations and later found our parameterisation to be a valid description of a wide range of other simulations and, therefore, reionisation physics.
Permanent Link: http://hdl.handle.net/11104/0321899