UC San Diego

We describe how thermally produced antielectron neutrinos (ν̄e) from the homologously collapsing core of a supermassive star (M ≳ 5 × 104 M⊙) can lead to significant deuterium enrichment in the ejected envelope of such a star. Deuterium-enriched material at high redshift might then serve as a clue to the existence of pregalactic supermassive stars. Conceivably, the ejected deuterium-enriched material could intercept the line of sight to a distant QSO and mimic a Lyman limit absorber. In such a case, the deuterium abundance inferred from absorption lines might not reflect the true primordial abundance of deuterium. We discuss relevant theoretical uncertainties in supermassive star physics as well as potential observational signatures in Lyα absorber clouds for processing by stars of this kind. © 1997. The American Astronomical Society. All rights reserved.