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Fine-tuning carbon-based life in the universe by the triple-alpha process in red giants

Heinz Oberhummer·Attila Csoto·Helmut Schlattl
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Abstract

Through the triple-alpha process occurring in red giant stars the bulk of the carbon existing in our universe is produced. We calculated the change of the triple-alpha reaction rate for slight variations of the nucleon-nucleon force using a microscopic 12-body model. Stellar model calculations for a low-mass, intermediate-mass and massive star using the different triple-alpha reaction rates obtained with different strengths of the N-N interaction have been performed. Even with a change of 0.4% in the strength of N-N force, carbon-based life appears to be impossible, since all the stars then would produce either almost solely carbon or oxygen, but could not produce both elements.

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Heinz Oberhummer, Attila Csoto, Helmut Schlattl. 1999-08-23. Fine-tuning carbon-based life in the universe by the triple-alpha process in red giants. https://doi.org/10.1142/9789812793324_0020

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