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arXiv · 2210.09156

Two Modes of LyC Escape From Bursty Star Formation: Implications for [C II] Deficits and the Sources of Reionization

Harley Katz·Aayush Saxena·Joki Rosdahl·Taysun Kimm·Jeremy Blaizot·Thibault Garel·Leo Michel-Dansac·Martin Haehnelt·Richard S. Ellis·Laura Penterrici·Julien Devriendt·Adrianne Slyz
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Abstract

We use the SPHINX$^{20}$ cosmological radiation hydrodynamics simulation to study how Lyman Continuum (LyC) photons escape from galaxies and the observational signatures of this escape. We define two classes of LyC leaker: Bursty Leakers and Remnant Leakers, based on their star formation rates (SFRs) that are averaged over 10 Myr (SFR$_{10}$) or 100 Myr (SFR$_{100}$). Both have $f_{\rm esc}>20\%$ and experienced an extreme burst of star formation, but Bursty Leakers have ${\rm SFR_{10}>SFR_{100}}$, while Remnant Leakers have ${\rm SFR_{10} 20\%$ dominate the ionizing photon budget at $z\gtrsim7.5$ but the contribution from galaxies with $f_{\rm esc}<5\%$ becomes significant at the tail-end of reionization.

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Harley Katz, Aayush Saxena, Joki Rosdahl, Taysun Kimm, Jeremy Blaizot, Thibault Garel, Leo Michel-Dansac, Martin Haehnelt, Richard S. Ellis, Laura Penterrici, Julien Devriendt, Adrianne Slyz. 2022-10-17. Two Modes of LyC Escape From Bursty Star Formation: Implications for [C II] Deficits and the Sources of Reionization. https://doi.org/10.1093/mnras%2Fstac3019

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