Papers › The effect of inhomogeneous reionisation on the Lyman-α forest power spectrum at...
The effect of inhomogeneous reionisation on the Lyman-α forest power spectrum at redshift z>4: implications for thermal parameter recovery
Margherita Molaro, Vid Iršič, James S. Bolton, Laura C. Keating, Ewald Puchwein, Prakash Gaikwad, Martin G. Haehnelt, Girish Kulkarni, Matteo Viel
The archive published only this paper's code-link row. Authors, date and abstract are from arXiv's metadata (CC0), read from the Kaggle arXiv metadata snapshot of 2026-09-12 where its title matched the archive's; the title is the archive's.
We use the Sherwood-Relics suite of hybrid hydrodynamical and radiative transfer simulations to model the effect of inhomogeneous reionisation on the 1D power spectrum of the \Lya forest transmitted flux at redshifts 4.2≤z ≤5. Relative to models that assume a homogeneous UV background, reionisation suppresses the power spectrum at small scales, k ∼0.1 km⁻¹ s by ∼10 per cent because of spatial variations in the thermal broadening kernel and the divergent peculiar velocity field associated with over-pressurised intergalactic gas. On larger scales, k<0.03 km⁻¹ s, the power spectrum is instead enhanced by $10$--$50$ per cent by large scale spatial variations in the neutral hydrogen fraction. The effect of inhomogeneous reionisation must therefore be accounted for in analyses of forthcoming high precision measurements. We provide a correction for the Lyα forest power spectrum at 4.1≤z ≤5.4 that can be easily applied within other parameter inference frameworks using similar reionisation models. We perform a Bayesian analysis of mock data to assess the extent of systematic biases that may arise in measurements of the intergalactic medium if ignoring this correction. At the scales probed by current high resolution Lyα forest data at z>4, 0.006 km⁻¹ s≤k ≤0.2 km⁻¹ s, we find inhomogeneous reionisation does not introduce any significant bias in thermal parameter recovery for the current measurement uncertainties of ∼10 per cent. However, for $5$ per cent uncertainties, ∼1σ shifts between the estimated and true parameters occur.
Code
Repository list and official/mentioned flags are the archive's, frozen 2025-07-28. Reachability, where shown, is from one Syntology probe window (2026-09-16 to 2026-09-18); repositories not probed show nothing. GitHub stars are not tracked.
Code Syntology ran Syntology
Not run by Syntology. Nothing on this page verifies that the listed code works.
Results from the paper archive 2025-07-28
No leaderboard rows for this paper in the archive.
Report a problem or propose a change · a person checks every report against the paper or source before anything changes; decisions are listed on /corrections