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arXiv · 2311.14558

GN-z11: witnessing the formation of second generation stars and an accreting massive black hole in a massive star cluster

F. D'Antona·E. Vesperini·F. Calura·P. Ventura·A. D'Ercole·V. Caloi·A. F. Marino·A. P. Milone·F. Dell'Agli·M. Tailo
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Abstract

We explore the possibility that the N-rich young proto-galaxy GN-z11 recently observed at z=10.6 by the James Webb Space Telescope is the result of the formation of second generation stars from pristine gas and Asymptotic Giant Branch (AGB) ejecta in a massive globular cluster or nuclear star cluster. We show that a second generation forming out of gas polluted by the ejecta of massive AGB stars and mixed with gas having a standard composition accounts for the unusually large N/O in the GN-z11 spectrum. The timing of the evolution of massive (4-7.5M$_{\odot}$) AGBs also provides a favourable environment for the growth of a central stellar mass black hole to the Active Galactic Nucleus stage observed in GN-z11. According to our model the progenitor system was born at an age of the Universe of $\simeq 260 - 380$Myr, well within the pre-reionization epoch.

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F. D'Antona, E. Vesperini, F. Calura, P. Ventura, A. D'Ercole, V. Caloi, A. F. Marino, A. P. Milone, F. Dell'Agli, M. Tailo. 2023-11-24. GN-z11: witnessing the formation of second generation stars and an accreting massive black hole in a massive star cluster. https://arxiv.org/abs/2311.14558

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