BibTeX

@article{2506.19925v2,
Author        = {Yannic Pietschke and Caroline Heneka and Tom Schlenker and Ayodele Ore and Benedikt Schosser},
Title         = {Direct reconstruction of the Reionization history from 21cm 2D Power
  Spectra},
Eprint        = {2506.19925v2},
DOI           = {10.1088/1475-7516/2025/10/039},
ArchivePrefix = {arXiv},
PrimaryClass  = {astro-ph.CO},
Abstract      = {The 21cm line from the spin-flip transition of neutral hydrogen (HI) provides
a unique window into the Epoch of Reionization (EoR), the final phase
transition of our Universe. The Square Kilometre Array (SKA) enables precise
measurements of 21cm fluctuations that trace ionization, temperature, and
density fluctuations of the intergalactic medium (IGM). Nevertheless, a direct
reconstruction of the timeline of the EoR in terms of the progress of
ionization remains an ongoing challenge due to the highly non-Gaussian nature
and thus intractable likelihood of the 21cm signal. Here, we present EoRFlow, a
simulation-based inference (SBI) framework for reconstructing the global
neutral hydrogen fraction $x_{\mathrm{HI}}(z)$ directly from 2D cylindrically
averaged power spectra (2DPS) of the 21cm signal. We validate our method on
realistic mock datasets for SKA-Low. Bypassing the need for explicit likelihood
formulations, our approach enables fast, unbiased posterior estimation of the
$x_{\mathrm{HI}}$ evolution in narrow redshift slices, allowing for piecewise
reconstruction of the global reionization history. By directly inferring the
reionization history from 21cm power spectra, our framework provides a scalable
and robust path forward for 21cm cosmology in the SKA era.},
Year          = {2025},
Month         = {Jun},
Note          = {JCAP10(2025)039},
Url           = {http://arxiv.org/abs/2506.19925v2},
File          = {2506.19925v2.pdf}
}