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The astrophysical $^7{rm Be}(p, gamma)^8{rm B}$ direct capture process is studied in the framework of a two-body single-channel model with potentials of the Gaussian form. A modified potential is constructed to reproduce the new experimental value of the $S$-wave scattering length and the known astrophysical $S$ factor at the Gamow energy, extracted from the solar neutrino flux. The resulting potential is consistent with the theory developed by Baye [Phys. Rev. C {bf 62} (2000) 065803] according to which the $S$-wave scattering length and the astrophysical $S$ factor at zero energy divided by the square of ANC are related. The obtained results for the astrophysical $S$ factor at intermediate energies are in good agreement with the two data sets of Hammache {it et al.} [Phys. Rev. Lett. {bf 86}, 3985 (2001); {it ibid.} {bf 80}, 928 (1998)]. Linear extrapolation to zero energy yields $ S_{17}(0) approx (20.5 pm 0.5) , rm eV , b $, consistent with the Solar Fusion II estimate. The calculated reaction rates are substantially lower than the results of the NACRE II collaboration.
The astrophysical $^{3}{rm He}(alpha, gamma)^{7}{rm Be}$ and $^{3}{rm H}(alpha, gamma)^{7}{rm Li}$ direct capture processes are studied in the framework of the two-body model with the potentials of a simple Gaussian form, which describe correctly the
Astrophysical $S$ factors and reaction rates of the direct radiative capture processes $^{3}{rm He}(alpha, gamma)^{7}{rm Be}$ and $^{3}{rm H}(alpha,gamma)^{7}{rm Li}$, as well as the primordial abundance of the $^{7}{rm Li}$ element, are estimated in
The ${^3{rm He}}(alpha,gamma){^7{rm Be}}$ and ${^3{rm H}}(alpha,gamma){^7{rm Li}}$ astrophysical $S$ factors are calculated within the no-core shell model with continuum using a renormalized chiral nucleon-nucleon interaction. The ${^3{rm He}}(alpha,
The reaction rates of the direct astrophysical capture processes $^{3}{rm He}(alpha, gamma)^{7}{rm Be}$ and $^{3}{rm H}(alpha,gamma)^{7}{rm Li}$, as well as the abundance of the $^{7}{rm Li}$ element are estimated in the framework of a two-body poten
At the long-wavelength approximation, electric dipole transitions are forbidden between isospin-zero states. In an $alpha+n+p$ model with $T = 1$ contributions, the $alpha(d,gamma)^6$Li astrophysical $S$-factor is in agreement with the experimental d