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Deformation effects in low-momentum distributions of heavy nuclei

V. O. Nesterenko·V. P. Likhachev·P. -G. Reinhard·J. Mesa·W. Kleinig·J. D. T. Arruda-Neto·A. Deppman
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Abstract

Momentum distributions (MD) of deep hole proton states in $^{238}$U are studied paying particular attention to the influence of deformation. Two essentially different mean-field models, Woods-Saxon (WS) and Skyrme-Hartree-Fock with the SkM$^*$ force, are used. Noticeable deviations between the WS and SkM$^*$ results are found. They are mainly due to the difference in effective nucleon mass. In particular, SkM$^*$ gives much weaker deformation effects at low momenta than WS. It is shown that, in spite of the deformation mixing, MD at low momenta can serve for identification of $K^π=1/2^+$ hole states originating from $s_{1/2}$ spherical sub-shells. Moreover, following the WS calculations, the deformation results in additional $K^π=1/2^+$ states with strong $l=0$ contributions. A possibility to probe such states in knock-out experiments is discussed.

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V. O. Nesterenko, V. P. Likhachev, P. -G. Reinhard, J. Mesa, W. Kleinig, J. D. T. Arruda-Neto, A. Deppman. 2003-02-13. Deformation effects in low-momentum distributions of heavy nuclei. https://arxiv.org/abs/nucl-th/0301046

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