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arXiv · 1302.6007

Anti-analog giant dipole resonances and the neutron skin of nuclei

A. Krasznahorkay·N. Paar·D. Vretenar·M. N. Harakeh
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Abstract

We examine a method to determine the neutron-skin thickness of nuclei using data on the charge-exchange anti-analog giant dipole resonance (AGDR). Calculations performed using the relativistic proton-neutron quasiparticle random-phase approximation (RQRPA) reproduce the isotopic trend of the excitation energies of the AGDR, as well as that of the spin-flip giant dipole resonances (IVSGDR), in comparison to available data for the even-even isotopes 112-124Sn. It is shown that the excitation energies of the AGDR, obtained using a set of density-dependent effective interactions which span a range of the symmetry energy at saturation density, supplemented with the experimental values, provide a stringent constraint on the value of the neutron-skin thickness. For 124Sn, in particular, we determine the value DRpn=0.21(5) fm. The result of the present study shows that a measurement of the excitation energy of the AGDR in (p,n) reactions using rare-isotope beams in inverse kinematics, provides a valuable method for the determination of the neutron-skin thickness in exotic nuclei.

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A. Krasznahorkay, N. Paar, D. Vretenar, M. N. Harakeh. 2013-02-25. Anti-analog giant dipole resonances and the neutron skin of nuclei. https://doi.org/10.1016/j.physletb.2013.02.043

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