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arXiv · 2404.10040

Anatomy of an ionized bubble: NIRCam grism spectroscopy of the $z=6.6$ double-peaked Lyman-$\alpha$ emitter COLA1 and its environment

Alberto Torralba-Torregrosa·Jorryt Matthee·Rohan P. Naidu·Ruari Mackenzie·Gabriele Pezzulli·Anne Hutter·Pablo Arnalte-Mur·Siddhartha Gurung-López·Sandro Tacchella·Pascal Oesch·Daichi Kashino·Charlie Conroy·David Sobral
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Abstract

The increasingly neutral intergalactic gas at $z>6$ impacts the Lyman-$\alpha$ flux observed from galaxies. One luminous galaxy, COLA1, stands out because of its unique double-peaked Ly$\alpha$ line at $z=6.6$, unseen in any simulation of reionization. Here we present JWST/NIRCam wide-field slitless spectroscopy in a 21 arcmin$^2$ field centered on COLA1. We find 141 galaxies spectroscopically-selected through the [OIII]($\lambda4969,5008$) doublet at $5.35 M_{\rm UV}>-19.5$).

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Alberto Torralba-Torregrosa, Jorryt Matthee, Rohan P. Naidu, Ruari Mackenzie, Gabriele Pezzulli, Anne Hutter, Pablo Arnalte-Mur, Siddhartha Gurung-López, Sandro Tacchella, Pascal Oesch, Daichi Kashino, Charlie Conroy, David Sobral. 2024-04-15. Anatomy of an ionized bubble: NIRCam grism spectroscopy of the $z=6.6$ double-peaked Lyman-$\alpha$ emitter COLA1 and its environment. https://doi.org/10.1051/0004-6361/202450318

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