Astrophysical S factors and reaction rates of the direct radiative capture processes ${}^3\mathrm{He}{(\alpha ,\gamma )}^7\mathrm{Be}$ and ${}^3\mathrm{H}{(\alpha ,\gamma )}^7\mathrm{Li}$, as well as the primordial abundance of the ${}^7\mathrm{Li}$ element, are estimated in the framework of a modified two-body potential model. It is shown that suitable modification of phase-equivalent $\alpha {-}^3$He potentials in the d waves can improve the description of the astrophysical S factor for the direct ${}^3\mathrm{He}{(\alpha ,\gamma )}^7\mathrm{Be}$ radiative capture reaction at energies above 0.5 MeV. An estimated ${}^7\mathrm{Li}/\mathrm{H}$ abundance ratio of $(4.89\pm 0.18)\times {10}^{-10}$ is in very good agreement with the recent measurement of $(5.0\pm 0.3)\times {10}^{-10}$ by the LUNA collaboration.

中文翻译：

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改进势模型法分析³ He（α，γ）⁷ Be和³ H（α，γ）⁷ Li天体物理直接捕获反应

天体物理S因子和直接辐射捕获过程的反应速率${}^3\mathrm{他}{（\alpha ，\gamma ）}^7\mathrm{是}$ 和 ${}^3\mathrm{H}{（\alpha ，\gamma ）}^7\mathrm{里}$以及原始的丰度 ${}^7\mathrm{里}$元素，是在修改后的两体电势模型的框架中估算的。结果表明，相当量的适当修改$\alpha {-}^3$d波中的势能可以直接描述天体S因子${}^3\mathrm{他}{（\alpha ，\gamma ）}^7\mathrm{是}$能量高于0.5 MeV时发生辐射捕获反应。估计${}^7\mathrm{里}/\mathrm{H}$ 的丰度比 $（4.89\pm 0.18）\times {10}^{-10}$ 与最近的测量非常吻合 $（5.0\pm 0.3）\times {10}^{-10}$ 由LUNA合作。