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arXiv · 1002.3854

Electron fraction constraints based on Nuclear Statistical Equilibrium with beta equilibrium

A. Arcones·G. Martinez-Pinedo·L. F. Roberts·S. E. Woosley
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Abstract

The electron-to-nucleon ratio or electron fraction is a key parameter in many astrophysical studies. Its value is determined by weak-interaction rates that are based on theoretical calculations subject to several nuclear physics uncertainties. Consequently, it is important to have a model independent way of constraining the electron fraction value in different astrophysical environments. Here we show that nuclear statistical equilibrium combined with beta equilibrium can provide such a constraint. We test the validity of this approximation in presupernova models and give lower limits for the electron fraction in type Ia supernova and accretion-induced collapse.

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A. Arcones, G. Martinez-Pinedo, L. F. Roberts, S. E. Woosley. 2010-02-22. Electron fraction constraints based on Nuclear Statistical Equilibrium with beta equilibrium. https://doi.org/10.1051/0004-6361/201014276

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