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arXiv · 1606.01304

Lyman-alpha and CIII] Emission in z=7-9 Galaxies: Accelerated Reionization Around Luminous Star Forming Systems?

Daniel P. Stark·Richard S. Ellis·Stephane Charlot·Jacopo Chevallard·Mengtao Tang·Sirio Belli·Adi Zitrin·Ramesh Mainali·Julia Gutkin·Alba Vidal-Garcia·Rychard Bouwens·Pascal Oesch
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Abstract

We discuss new Keck/MOSFIRE spectroscopic observations of four luminous galaxies at z~7-9 selected to have intense optical line emission by Roberts-Borsani et al. (2016). Previous follow-up has revealed Lyman-alpha in two of the four galaxies. Our new MOSFIRE observations confirm that Lyman-alpha is present in the entire sample. We detect Lyman-alpha emission in COS-zs7-1, confirming its redshift as z=7.154, and we detect Lyman-alpha in EGS-zs8-2 at z=7.477, verifying a tentative detection presented in an earlier study. The ubiquity of Lyman-alpha in this sample is puzzling given that the IGM is likely significantly neutral over 7 7 is expected to be strongly luminosity-dependent, with the most effective transmission occurring in systems with intense star formation.

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Daniel P. Stark, Richard S. Ellis, Stephane Charlot, Jacopo Chevallard, Mengtao Tang, Sirio Belli, Adi Zitrin, Ramesh Mainali, Julia Gutkin, Alba Vidal-Garcia, Rychard Bouwens, Pascal Oesch. 2016-06-03. Lyman-alpha and CIII] Emission in z=7-9 Galaxies: Accelerated Reionization Around Luminous Star Forming Systems?. https://doi.org/10.1093/mnras%2Fstw2233

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