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Computation of Atmospheric Concentrations of Molecular Clusters from ab initio Thermochemistry
Published on: April 8, 2020
Ab initio calculation of the Hoyle state.
Evgeny Epelbaum1, Hermann Krebs, Dean Lee
1Institut für Theoretische Physik II, Ruhr-Universität Bochum, D-44870 Bochum, Germany.
Physical Review Letters
|June 15, 2011
Summary
Researchers used supercomputer lattice simulations to uncover the nature of the Hoyle state, a key excited state in carbon-12 nuclei crucial for stellar helium burning and life
Area of Science:
- Nuclear Physics
- Computational Astrophysics
- Stellar Nucleosynthesis
Background:
- The Hoyle state is an excited state of carbon-12 essential for helium burning in stars and the production of elements necessary for life.
- Despite experimental observation over 50 years ago, the fundamental nature of the Hoyle state remains unexplained by nuclear theorists.
- Understanding the Hoyle state is critical for accurately modeling stellar evolution and nucleosynthesis in stars heavier than the Sun.
Purpose of the Study:
- To perform the first ab initio calculation of low-lying states in carbon-12.
- To elucidate the fundamental nature of the Hoyle state from first principles using advanced computational methods.
- To validate theoretical predictions against experimental observations of the Hoyle state's properties.
Main Methods:
- Employed supercomputer lattice simulations to model the carbon-12 nucleus.
- Utilized a theoretical framework based on effective field theory for the calculations.
- Calculated the ground state, an excited spin-2 state, and a resonance characteristic of the Hoyle state.
Main Results:
- Successfully calculated the ground state and an excited spin-2 state of carbon-12.
- Identified a resonance at -85(3) MeV, exhibiting all properties consistent with the experimentally observed Hoyle state.
- The calculated energy of the Hoyle state resonance agrees with experimental measurements.
Conclusions:
- This study presents the first ab initio calculation of the Hoyle state, providing fundamental insights into its nature.
- The results confirm the existence and properties of the Hoyle state using advanced computational nuclear physics.
- The findings offer a significant step forward in understanding stellar nucleosynthesis and the origin of elements essential for life.
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