The production of ionizing photons in UV-faint z~3-7 galaxies

Gonzalo Prieto-Lyon; Victoria Strait; Charlotte A. Mason; Gabriel Brammer; Gabriel B. Caminha; Amata Mercurio; Ana Acebron; Pietro Bergamini; Claudio Grillo; Piero Rosati; Eros Vanzella; Marco Castellano; Emiliano Merlin; Diego Paris; Kristan Boyett; Antonello Calabrò; Takahiro Morishita; Sara Mascia; Laura Pentericci; Guido Roberts-Borsani; Namrata Roy; Tommaso Treu; Benedetta Vulcani

doi:10.1051/0004-6361/202245532

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arXiv · 2211.12548

The production of ionizing photons in UV-faint z~3-7 galaxies

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Abstract

The demographics of the production and escape of ionizing photons from UV-faint early galaxies is a key unknown in discovering the primary drivers of reionization. With the advent of JWST it is finally possible to observe the rest-frame optical nebular emission from individual sub-L$^*$ z>3 galaxies to measure the production of ionizing photons, $\xi_\mathrm{ion}$. Here we study a sample of 370 z~3-7 galaxies spanning -23 0.5) in our sample, based on their photometric properties, even amongst the Lyman-alpha selected galaxies. This work demonstrates that considering the full distribution of $\xi_\mathrm{ion}$ across galaxy properties is important for assessing the primary drivers of reionization.

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Gonzalo Prieto-Lyon, Victoria Strait, Charlotte A. Mason, Gabriel Brammer, Gabriel B. Caminha, Amata Mercurio, Ana Acebron, Pietro Bergamini, Claudio Grillo, Piero Rosati, Eros Vanzella, Marco Castellano, Emiliano Merlin, Diego Paris, Kristan Boyett, Antonello Calabrò, Takahiro Morishita, Sara Mascia, Laura Pentericci, Guido Roberts-Borsani, Namrata Roy, Tommaso Treu, Benedetta Vulcani. 2022-11-22. The production of ionizing photons in UV-faint z~3-7 galaxies. https://doi.org/10.1051/0004-6361%2F202245532

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