The anthropic significance of the existence of an excited state of 12C

@article{Livio1989TheAS,
  title={The anthropic significance of the existence of an excited state of 12C},
  author={Mario Livio and David Earl Hollowell and Achim Weiss and James W. Truran},
  journal={Nature},
  year={1989},
  volume={340},
  pages={281-284}
}
Were it not for the presence of an excited state of 12C at 7.6 MeV, at the endpoint of the triple-alpha reaction, it would be difficult for stars to manufacture carbon and heavier elements. Calculations using modified triple-alpha rates test the sensitivity of stellar nucleosynthesis to the exact position of this excited state, and allow an empirical assessment of its importance in the anthropic principle in cosmology. 
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References

SHOWING 1-10 OF 12 REFERENCES
The 7.68-Mev state in C12
Magnetic analysis of the alpha-particle spectrum from N14(d, α)C12 covering the excitation energy range from 4.4 to 9.2 Mev in C12 shows a level at 7.68±0.03 Mev. At Ed=620 kev, θlab=90°, transitions
Large Number Coincidences and the Anthropic Principle in Cosmology
Prof. Wheeler has asked me to say something for the record about some ideas that I once suggested (at the Clifford Memorial meeting in Princeton in 1970) and to which Hawking and Collins have
Pulsation and Mass Loss for AGB Stars
Mechanisms of mass loss are reviewed, with some general comments. The effects of pulsation on the structure of the atmosphere and on the efficiency with which mass loss occurs are described, and
Asymptotic giant branch evolution of intermediate-mass stars as a function of mass and composition. II. Through the first major thermal pulse and the consequences of convective dredge-up
The aysmptotic giant branch evolution of intermediate-mass stars is further investigated following the end of the second dredge-up phase. The limiting mass for nondegenerate core carbon ignition is
Theoretical Aspects of Pulsation and Envelope Ejection in Red Giants
Observational Q values for globular cluster red variables, Mira variables and red supergiant variables have been compared with appropriate theoretical Q values in an attempt to find the mode(s) of
...
1
2
...