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arXiv · 1410.1652

Sensitivity of the Blue Loops of Intermediate-Mass Stars to Nuclear Reactions

Ghina M. Halabi·Mounib El Eid
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Abstract

We investigate the effects of a modification of the $^{14}$N(p,γ)$^{15}$O reaction rate, as suggested by recent evaluations, on the formation and extension of the blue loops encountered during the evolution of the stars in the mass range 5M$_{\odot}$ to 12M$_{\odot}$. We show that the blue loops of stars in the mass range 5M$_{\odot}$ to 8M$_{\odot}$, that is the range of super ABG stars, are severely affected by a modification of the important $^{14}$N(p,γ)$^{15}$O reaction rate. We also show that the blue loops can be restored if envelope overshooting is included, which is necessary to explain the observations of the Cepheid stars.

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Ghina M. Halabi, Mounib El Eid. 2014-10-07. Sensitivity of the Blue Loops of Intermediate-Mass Stars to Nuclear Reactions. https://arxiv.org/abs/1410.1652

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