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arXiv · 2412.01906

The ionizing photon budget and effective clumping factor in radiative transfer simulations calibrated to Lyman-alpha forest data

Shikhar Asthana·Girish Kulkarni·Martin G. Haehnelt·James S. Bolton·Laura C. Keating·Charlotte Simmonds
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Abstract

Recent JWST observations have allowed for the first time to obtain comprehensive measurements of the ionizing photon production efficiency $\xi_\text{ion} $ for a wide range of reionization-epoch galaxies. We explore implications for the inferred UV luminosity functions and escape fractions of ionizing sources in our suite of simulations. These are run with the GPU-based radiative transfer code ATON-HE and are calibrated to the XQR-30 Lyman-alpha forest data at $5 50$% at $z> 10$, disfavouring the oligarchic source model at very high redshift. The inferred effective clumping factors in our simulations are in the range of $3-6$, suggesting consistency between the observed ionizing properties of reionization-epoch galaxies and the ionizing photon budget in our simulations.

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Shikhar Asthana, Girish Kulkarni, Martin G. Haehnelt, James S. Bolton, Laura C. Keating, Charlotte Simmonds. 2024-12-02. The ionizing photon budget and effective clumping factor in radiative transfer simulations calibrated to Lyman-alpha forest data. https://arxiv.org/abs/2412.01906

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