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تسجيل مستخدم جديدSpin-flip doublets of $^9$Be spectrum within a cluster model
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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 corresponding to the total orbital momentum ($L^pi=0^+, 2^+,4^+, 1^-, 2^-,3^-, 4^-$) of the system. The Ali-Bodmer potential (model E) is applied for the $alphaalpha$ interaction. We employ a local $alpha n$ potential which was constructed to reproduce the $alpha-n$ scattering data. The Pauli blocking is simulated by the repulsive core of the $s$-wave components of these potentials. Configuration space Faddeev equations are used to calculate the energy of the bound state ($E_{cal.}$=-1.493 MeV v.s. $E_{exp.}$=-1.5735 MeV) and resonances. A variant of the method of analytical continuation in the coupling constant is applied to calculate the energies of low-lying levels. Available $^9$Be spectral data are satisfactorily reproduced by the proposed model.
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