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arXiv · 0807.0089

A dependence of the enhancement factor in energy-weighted sums for isovector giant resonances

V. M. Kolomietz·S. V. Lukyanov
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Abstract

We consider the energy weighted sums (EWS) for isovector giant dipole resonances (IVGDR) in finite nuclei within Landau kinetic theory. The dependence of both IVGDR energy, $E_{IVGDR}$, and the EWS enhancement factor, $κ(A)$, on the mass number $A$ occurs because of the boundary condition on the moving nuclear surface. The values of $E_{IVGDR}A^{1/3}$ and $κ(A)$ increase with $A$. The obtained value of the enhancement factor is about 10% for light nuclei and reaches approximately 20% for heavy nuclei. A fit of the enhancement factor to the proper experimental data provides a value for the isovector Landau amplitude of $F'_1\simeq 1.1$.

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V. M. Kolomietz, S. V. Lukyanov. 2009-04-21. A dependence of the enhancement factor in energy-weighted sums for isovector giant resonances. https://doi.org/10.1103/physrevc.79.024321

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