Low - lying resonances of 9 Λ Be : Faddeev calculation with Pade - approximants
نویسنده
چکیده
Configuration space Faddeev equations are applied to describe the ΛBe hypernucleus in the ααΛ cluster model. For calculation of resonance state energies a variant of the method of analytical continuation in coupling constant is used. To realize this method, an auxiliary three-body potential is added to the Hamiltonian of the equations. A proper choice of strength parameter of the potential converts a resonance state into a bound state and an energy trajectory is obtained by variations of this parameter. To fulfill analytical continuation of this trajectory as a function of the strength parameter onto the complex plane, the Pade’ approximation is used. Spectrum of low-lying resonances is calculated with two αΛ phenomenological potentials. We predict existence of the 02 and 41 virtual states as well as the 2 + 2 resonance state near by the ααΛ threshold. The Be(L)+Λ(s-wave) configuration for description of the ΛBe ground band is discussed.
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