Observations suggest that UV-bright, compact star-forming galaxies produce enough ionizing (Lyman continuum; LyC) photons to reionize the Universe. Yet, the efficiency of LyC escape and the roles of radiation, stellar winds, and supernovae remain uncertain. Using medium-resolution spectra of six nearly identical local star-forming galaxies, we directly trace, for the first time, the evolution of a multiphase wind through individual spectral lines alongside measurements of the LyC escape fraction. We find that LyC escape peaks early, during a period dominated by intense radiation and stellar winds but lacking a fast galactic wind. As the starbursts age, supernovae drive and accelerate the wind, progressively suppressing LyC escape. These results highlight the need for cosmological simulations to incorporate early feedback as a key driver of reionization.
@article{arxiv.2510.21197,
title = {Supernovae Driven Winds Impede Lyman Continuum Escape from Dwarf Galaxies in First 10 Myr},
author = {Cody Carr and Renyue Cen and Stephan McCandliss and Jack Ford and Alberto Saldana-Lopez and Claudia Scarlata and Mason Huberty and Anne Jaskot and Sophia Flury and M. S. Oey and Ricardo O. Amorín and Sanchayeeta Borthakur and Matthew Hayes and Timothy Heckman and Zhiyuan Ji and Lena Komarova and Alexandra Le Reste and Floriane Leclercq and Rui Marques-Chaves and Leo Michel-Dansac and Göran Östlin and Swara Ravindranath and Michael J. Rutkowski and Daniel Schaerer and Trinh Thuan and Eros Vanzella and Bingjie Wang and Xinfeng Xu},
journal= {arXiv preprint arXiv:2510.21197},
year = {2025}
}