Measurement of the C12(C12,p)Na23 cross section near the Gamow energy

The fusion reaction C-12 (C-12 ,p)Na-23 has been studied from E = 2.00 to 4.00 MeV by particle spectroscopy. The data reveal broad resonances above E = 3.00 MeV and are compatible with previously reported resonance structure around E = 2.1 MeV. The data were limited at low energies by low count rates as well as possible background contributions. This experiment extends the previously achieved low-energy measurement by charged particle spectroscopy to 2 MeV, which corresponds to the high-energy side of the astrophysically relevant temperature. Present knowledge of level structures and nonresonant contribution cannot explain the results of the present experiment, which may change the C-12 + C-12 reaction rate significantly. Despite the progress decreasing the low-energy limit, any extrapolation into the astrophysical energy range remains highly uncertain based on available experimental data