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arXiv · 1204.6260

Fragmentation of spin-dipole strength in $^{90}$Zr and $^{208}$Pb

T. Marketin·E. Litvinova·D. Vretenar·P. Ring
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Abstract

An extension of time-dependent covariant density functional theory that includes particle-vibration coupling is applied to the charge-exchange channel. Spin-dipole excitation spectra are calculated an compared to available data for $^{90}$Zr and $^{208}$Pb. A significant fragmentation is found for all three angular-momentum components of the spin-dipole strength as a result of particle-vibration coupling, as well as a shift of a portion of the strength to higher energy. A high-energy tail is formed in the strength distribution that linearly decreases with energy. Using a model-independent sum rule,the corresponding neutron skin thickness is estimated and shown to be consistent with values obtained at the mean-field level.

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T. Marketin, E. Litvinova, D. Vretenar, P. Ring. 2012-04-27. Fragmentation of spin-dipole strength in $^{90}$Zr and $^{208}$Pb. https://doi.org/10.1016/j.physletb.2011.11.050

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