Determination of the astrophysical S factor of the 8B(p,γ)9C capture reaction from the d(8B,9C)n reaction

Breakup and Finite-Range Effects on the 8B(d,n)9C Reaction

“…The result for S 18 (0) in the present study, 22 ± 6 eV b, is somewhat smaller than the result from the previous analysis (45 ± 13 eV b) extracted from the same experimental data [4] with the distorted-wave Born approximation (DWBA), which does not explicitly take into account the breakup states of nuclei. In this section we discuss this difference in view of the breakup effects of d and 9 C in the transfer reaction.…”

“…A problem with the results of the indirect measurements of S 18 (0) is that they are not consistent with each other, with values of 46 ± 6 eV b (from inclusive 9 C breakup [2]), 77 ± 15 eV b (from exclusive 9 C breakup [3]), and 45 ± 13 eV b (from transfer [4]). In Ref.…”

“…The solid line shows the CCBA result. We have normalized the result to reproduce the experimental data [4] multiplied by S = 0.361. Note that, from the present transfer reaction, S cannot be determined because the reaction is peripheral, as will be confirmed below.…”

“…By compiling the uncertainties due to peripherality (2%) and the optical potential (3%) as well as the experimental error of 22% [4], we obtain (C 9 C p 8 B ) 2 = 0.59 ± 0.02 (theor.) ± 0.13 (exp.)…”

“…The proton capture reaction of 8 B, 8 B(p,γ) 9 C, is expected to lead to this hot pp chain. Since it is very difficult to measure the cross section σ pγ for the 8 B(p,γ) 9 C reaction at stellar energies, several experiments of alternative reactions such as the inclusive [2] and exclusive [3] 9 C breakup reactions and the proton transfer reaction 8 B(d,n) 9 C [4] have been done to determine the astrophysical factor S 18 (ε pB ) = σ pγ ε pB exp[2πη].…”