Influence of the three-body coulomb effects on the values of asymptotic normalization coefficients (nuclear vertex constants) of astrophysical interest extracted from the modified DWBA approach for the peripheral proton-transfer reactions

Asymptotic normalization coefficients for Be7+p→B8 from the peripheral Tojiboev1, Yarmukhamedov2, Artemov3 et al. 2016Phys. Rev. CSelf Cite14150View full textAdd to dashboardCite

“…However, the obtained value for C 2 B differs noticeably from that recommended in [16,24,46,47]. As we discussed above, the ANC value of [16] is model dependent [9,19,20,51] on account of using the first order over the ∆V C f potential. The ANC value of [24] and the discussed theoretical uncertainty of it, which can easily be obtained using the S 17 (0) value derived in [24] (see , Table 4) and its relation with the ANC given there, is also model dependent because of the fairly large ambiguity for the spectroscopic factors.…”

“…The analysis was performed within the modified DWBA restricting by the first order of the perturbation theory over the Coulomb polarization potential (∆V C f ) in the transition operator and assuming that its contribution to the total transition operator is small. But, the ANC values proposed in [16] may not have sufficient accuracy because of the aforementioned assumption made for the transition operators [19,20]. Nevertheless, in [16] the obtained ANC values were then used for the estimation of S 17 (0), which also differs noticeably from that recommended in [8,10,21].…”

“…Thus, introduction of the conditions (5) and (6) into the DWBA analysis guarantees the correct absolute normalization of the peripheral reaction cross section and supports the assumption about the dominance of the peripheral character of the proton transfer within (or near) the main peak region of the angular distribution, which is mainly determined by the true peripheral partial-wave amplitudes at l >>1 [19]. Therefore, fulfilment (or weak violation within the errors of the experimental differential cross section dσ exp /dΩ) of the conditions (5) and (6) makes it possible to obtain the experimental ("indirectly determined") value of squared…”

“…The main contribution to the full transition operator in the amplitude (at least near the main peak region in the angular distribution) comes from the proton-neutron nuclear V N np potential [19,30,31] since ∆V C f =0 in the full transition operator because of the presence of a neutron in the final state. Then the single particle DWBA cross section can be calculated within the finite range DWBA in the "post"-approximation with the DWUCK5 code.…”

Extrapolation of astrophysical S factors for the reaction 14N((p, γ) 15O to near-zero energies

“…The contribution of three-particle (p−d− 14 N) Coulomb dynamics (associated with all possible Coulomb rescattering processes involving p, d, and 14 N particles in the intermediate reaction state) in the pole mechanism of proton transfer in expression (1) was taken into account by a method similar to that used in [29][30][31]-that is, by introducing the Coulomb renormalization factor R 2 on the right-hand side of Eq. (1).…”