Coulomb displacement energy and the low-energy astrophysical S17 factor for the 7Be(p,γ)8B reaction

Abstract

The relationship between the Coulomb displacement energy for the A=8, J=2 + , T=1 state and the low-energy astrophysical S 17 factor for the 7 Be(p,γ) 8 B reaction is discussed. The displacement energy is interpreted in a particle-hole model. The dependence of the particle displacement energy on the potential well geometry is investigated and is used to relate the particle displacement energy to the rms radius and the asymptotic normalization of the valence proton wave function in 8 B. The asymptotic normalization is used to calculate the astrophysical S 17 factor for the 7 Be(p,γ) reaction. The relationship to the 7 Li(n,γ) reaction, the 8 B quadrupole moment, radial density, and break-up momentum distribution are also discussed.

Structure of8B and astrophysicalS17factor

“…However, once the relevant integration distances are sufficiently enhanced in [11] the value of κ there comes out to be 37.2, which is in good agreement with that of the microscopic model. In our calculations, we have used our HF overlap function directly in the calculation of the amplitudes for the direct capture reaction.…”

“…The SkHF method with density-dependent pairing correlation and SLy4 interaction parameters has been successful in reproducing the binding energies and rms radii [14] in the light neutron halo nuclei 6 He, 8 He, 11 Li and 14 Be. We solve spherically symmetric Hartree-Fock (HF) equations with SLy4 [15] Skyrme interaction which has been constructed by fitting to the experimental data on radii and binding energies of symmetric and neutron-rich nuclei.…”

Effects of 8B size on the low-energy 7Be(p,γ)8B cross section

“…This effect is estimated to cause a ≈130 keV shift in the E( [16]. So we should compare our results to a phenomenological value of ∆ = 3.54 − 0.13 = 3.41 MeV.…”

“…A possible way to constrain the interaction radius is to study some key properties of the A = 7 and 8 nuclei [15]. The observables that are most sensitive to the interaction radius are "size-like" properties, for example, quadrupole moment, radius, Coulomb displacement energy [16], etc. These are the quantities which we will calculate in our microscopic cluster model and then study their effect on the astrophysical S factor.…”

Breakup reactions of the halo nucleiBe11andBHencken1, Bertsch2, Esbensen3 1996Phys. Rev. C185102501View full textAdd to dashboardCite

“…The determination of the size of the core potential is crucial for the prediction of the S-factor for the p + 7 Be → 8 B radiative capture process, see, e.g, ref. [23].…”