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Temperature dependence of modified CNO nuclear reaction rates in dense stellar plasmas

F. Ferro·A. Lavagno·P. Quarati
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Abstract

We study the dependence of the CNO nuclear reaction rates on temperature, in the range of $10^7÷10^8$ K, the typical range of temperature evolution from a Sun-like star towards a white dwarf. We show that the temperature dependence of the CNO nuclear reaction rates is strongly affected by the presence of non-extensive statistical effects in the dense stellar core. A very small deviation from the Maxwell-Boltzmann particle distribution implies a relevant enhancement of the CNO reaction rate and could explain the presence of heavier elements (e.g. Fe, Mg) in the final composition of a white dwarf core. Such a behavior is consistent with the recent experimental upper limit to the fraction of energy that the Sun produces via the CNO fusion cycle.

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F. Ferro, A. Lavagno, P. Quarati. 2003-12-24. Temperature dependence of modified CNO nuclear reaction rates in dense stellar plasmas. https://doi.org/10.1016/j.physa.2004.04.043

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