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Structure of and E2 transition in $^{16}$C in a $^{14}$C+n+n model

W. Horiuchi·Y. Suzuki
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Abstract

A three-body model of $^{14}$C+n+n is applied to study the energy spectrum and the hindered $E$2 transition in $^{16}$C. A realistic two-nucleon potential is used for the valence neutrons. Both spin singlet and triplet components for the neutrons are taken into account. The three-body problem with a Pauli constraint is solved in a stochastic variational method. For the n-$^{14}$C potential chosen to reproduce the properties of $^{15}$C, the low-lying energy spectrum agrees reasonably well with experiment, but the ground state is predicted to be about 1 MeV high. The calculated $B(E2$; $2_1^+ \to 0^+_1)$ value is about twice the measured value if the polarization charge of the valence neutrons is taken to be the same as that required to fit the $^{15}$C data. The correlated motion of the valence neutrons is displayed through the two-neutron density distribution.

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W. Horiuchi, Y. Suzuki. 2006-01-20. Structure of and E2 transition in $^{16}$C in a $^{14}$C+n+n model. https://doi.org/10.1103/physrevc.73.037304%2010.1103%2Fphysrevc.74.019901

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