Constraining the 6.05 MeV 0$^+$ and 6.13 MeV 3$^-$ cascade transitions   in the $^{12}$C($\alpha$,$\gamma$)$^{16}$O reaction using the Asymptotic   Normalization Coefficients
  Background. The $^{12}$C$(\alpha,\gamma)^{16}$O reaction plays a fundamental role in astrophysics and needs to be known with accuracy better than 10%. Cascade $\gamma$ transitions through the excited states of $^{16}$O are contributing to the uncertainty.   Purpose. To constrain the contribution of the 0$^+$ (6.05 MeV) and 3$^-$ (6.13 MeV) cascade transitions.   Method. The $\alpha$ Asymptotic Normalization Coefficient for these states were measured using the $\alpha$-transfer reaction $^{12}$C$(^6$Li,$d)^{16}$O at sub-Coulomb energies.   Results. The 0$^+$ and 3$^-$ cascade transitions contribution was found to be 1.96$\pm$0.3 keV b and 0.12$\pm$0.04 keV b for destructive interference of the direct and resonance capture and 4.36$\pm$0.45 keV b and 1.44$\pm$0.12 keV b for constructive interference respectively.   Conclusions. The combined contribution of the 0$^+$ and 3$^-$ cascade transitions to the reaction at 300 keV does not exceed 4%. Significant uncertainties have been dramatically reduced. 
M. L. Avila, G. V. Rogachev, E. Koshchiy, L. T. Baby, J. Belarge, K.   W. Kemper, A. N. Kuchera, A. M. Mukhamedzhanov, D. Sa...
nucl-ex