A new ${}^{12}$C + ${}^{12}$C nuclear reaction rate: impact on stellar evolution

Abstract

This work presents new ${}^{12}$C + ${}^{12}$C reaction rates in the form of numerical tables with associated uncertainty estimation, as well as analytical formulae that can be directly implemented into stellar evolution codes. This article further describes the impact of these new rates on C-burning in stars. We determine reaction rates for two cross-section extrapolation models: one based on the fusion-hindrance phenomenon, and the other on fusion-hindrance plus a resonance, and compare our results to previous data. Using the GENEC stellar evolution code, we study how these new rates impact the C-burning phases in two sets of stellar models for stars with 12 M${}_{\odot }$ and 25 M${}_{\odot }$ initial masses chosen to be highly representative of the diversity of massive stars. The effective temperatures of C-burning in both sets of stellar models are entirely covered by the sensitivity of the present experimental data, and no extrapolation of the rates is required. Although, the rates may differ by more than an order of magnitude for temperatures typical of C-burning, the impacts on the stellar structures during that phase remain modest. This is a consequence of the readjustment of the stellar structure to a change of nuclear reaction rate for reactions important for energy production. For the hindrance case, the C-burning phase is found to occur at central temperatures 10\% higher than with the hindrance plus resonance rate. Its C-burning lifetime is reduced by a factor of two. This model, nevertheless, loses more entropy than the other one thus enters earlier into the degeneracy regime which will impact the last stages of the evolution at the pre-core collapse time. The hindrance model produces up to 60% more neon. The impact of the different rates on the s-process occurring during the C-burning phase is modest, changing final abundances of s-processed elements by at most 20% (cobalt).

13 pages, 9 figures

References in corpus (9)

• Hindrance of heavy-ion fusion due to nuclear incompressibility
• Study of the 12C+12C fusion reactions near the Gamow energy
• The 12C + 12C reaction and the impact on nucleosynthesis in massive stars
• How the Pauli exclusion principle affects fusion of atomic nuclei
• On the proper use of the Schwarzschild and Ledoux criteria in stellar evolution computations
• New measurement of ${}^{12}$C+${}^{12}$C fusion reaction at astrophysical energies
• Existence of One-Body Barrier Revealed in Deep Sub-Barrier Fusion
• The impact of the new measurement of the ${}^{12}\mathrm{C}{+}^{12}\mathrm{C}$ fusion cross section on the final compactness of the massive stars
• The first direct measurement of 12C(12C,n)23Mg at stellar energies

Cited by in corpus (9)

• Nuclear Quantum Many-Body Dynamics: From Collective Vibrations to Heavy-Ion Collisions (2nd edition)
• Massive stars evolution with new C12+C12 nuclear reaction rate -- the core carbon-burning phase
• Cluster model of 12C in density functional theory framework
• Stellar Neutrino Emission Across The Mass-Metallicity Plane
• The composition of massive white dwarfs and their dependence on the C-burning modeling
• Refining the deep sub-barrier 12C+12C excitation function with STELLA
• Nuclear Reactions in Evolving Stars
• Impact of stellar rotation on type II supernova progenitor masses from pre-explosion imaging
• Carbon burning at stellar energies