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arXiv · 1907.11013

Studies of quasiclassical approach applicability to true three-body decays

O. M. Sukhareva·L. V. Grigorenko·D. A. Kostyleva·M. V. Zhukov
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Abstract

Within the hyperspherical harmonics approach the three-body problem is reduced to a motion of one effective particle in a "strongly deformed" field, which is described in coupled-channel formalism. This method is especially suited to studies of phenomena characterized by genuine three-body dynamics, e.g. Borromean haloes and true three-body decays. The reduction of the hyperspherical equations set to a single-channel Schrödinger equation provides the basis for the use of the standard quasiclassical expression for calculations of widths for true three-body decays. We demonstrate that the quasiclassical approach by itself is quite precise in application to typical profiles of the three-body effective potentials. However, the reduction to single-channel formalism leads to significant overestimation of the two-proton width $Γ_{2p}$. This is demonstrated by the example of the $^{17}$Ne first excited $3/2^-$ state decay, questioning, however, the applicability of such an approximation in general.

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O. M. Sukhareva, L. V. Grigorenko, D. A. Kostyleva, M. V. Zhukov. 2019-07-25. Studies of quasiclassical approach applicability to true three-body decays. https://arxiv.org/abs/1907.11013

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