Low-Energy Direct Capture in the 8Li(n,gamma)9Li and 8B(p,gamma)9C Reactions

The cross sections of the 8Li(n,gamma)9Li and 8B(p,gamma)9C capture reactions have been analyzed using the direct capture model. At low energies which is the astrophysically relevant region the capture process is dominated by E1 transitions from incoming s-waves to bound p-states. The cross sections of both mirror reactions can be described simultaneously with consistent potential parameters, whereas previous calculations have overestimated the capture cross sections significantly. However, the parameters of the potential have to be chosen very carefully because the calculated cross section of the 8Li(n,gamma)9Li reaction depends sensitively on the potential strength.