Sensitivity of the Blue Loops of Intermediate-Mass Stars to Nuclear   Reactions
  We investigate the effects of a modification of the $^{14}$N(p,{\gamma})$^{15}$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,{\gamma})$^{15}$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. 
Ghina M. Halabi, Mounib El Eid
astro-ph.SR