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arXiv · 2502.18098

The mass distribution of the first stars can be determined via the 21-cm signal

T. Gessey-Jones·N. S. Sartorio·H. T. J. Bevins·A. Fialkov·W. J. Handley·E. de Lera Acedo·G. M. Mirouh·R. G. Izzard·R. Barkana
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Abstract

The formation of the first stars and the subsequent population of X-ray binaries represents a fundamental transition in the state of the Universe as it evolves from near homogeneity to being abundant in collapsed structures such as galaxies. Due to a lack of direct observations, the properties of these stars remain highly uncertain. By considering the impact of the first stars and their remnant X-ray binaries on the cosmological 21-cm signal, we demonstrate that upcoming observations have the potential to significantly improve our understanding of these objects. We find a 25 mK sensitivity measurement of the 21-cm global signal by a wide-beam radiometer, such as REACH, or 3,000 hours of foreground avoidance observations of the 21-cm power spectrum by SKA-Low, could provide three-sigma constraints on the mass distribution of the first stars. Such measurements will fill a critical gap in our understanding of the early Universe and aid in interpreting high-redshift galaxy observations.

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T. Gessey-Jones, N. S. Sartorio, H. T. J. Bevins, A. Fialkov, W. J. Handley, E. de Lera Acedo, G. M. Mirouh, R. G. Izzard, R. Barkana. 2025-02-25. The mass distribution of the first stars can be determined via the 21-cm signal. https://doi.org/10.1038/s41550-025-02575-x

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