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Isoscalar giant monopole resonance and its overtone in microscopic and macroscopic models

S. Shlomo·V. M. Kolomietz·B. K. Agrawal
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Abstract

We calculate the transition density for the overtone of the isosclar giant monopole resonance (ISGMR) from the response to an appropriate external field $\hat{f}_ξ(r)$ obtained using the seemiclassical fluid dynamic approximation and the Hartree-Fock (HF) based random phase approximation (RPA). We determine the mixing parameter $ξ$ by maximizing the ratio of the energy weighted sum for the overtone mode to the total energy weighted sum rule and derive a simple expression for the microscopic transition density associated with the overtone mode. This macroscopic transition density agrees well with that obtained from the HF-RPA calculations. We also point out that the ISGMR and its overtone can be clearly identified by considering the response to the electromagnetic external field $\hat{j}_o(qr)$ .

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S. Shlomo, V. M. Kolomietz, B. K. Agrawal. 2003-10-31. Isoscalar giant monopole resonance and its overtone in microscopic and macroscopic models. https://doi.org/10.1103/physrevc.68.064301

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