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تسجيل مستخدم جديدAstrophysical reaction rate for $^9$Be formation within a three-body approach
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The structure of the Borromean nucleus $^9$Be ($alpha+alpha+n$) is addressed within a three-body approach using the analytical transformed harmonic oscillator method. The three-body formalism provides an accurate description of the radiative capture reaction rate for the entire temperature range relevant in Astrophysics. At high temperatures, results match the calculations based on two-step sequential processes. At low temperatures, where the particles have no access to intermediate two-body resonances, the three-body direct capture leads to reaction rates larger than the sequential processes. These results support the reliability of the method for systems with several charged particles.
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The structure of the $^9$Be low-lying spectrum is studied within the cluster model $alpha+alpha+n$. In the model the total orbital momentum is fixed for each energy level. Thus each level is determined as a member of the spin-flip doublet correspondi
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