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arXiv · 1304.5155

A beyond-mean-field example with zero-range effective interactions in infinite nuclear matter

K. Moghrabi·M. Grasso·X. Roca-Maza·G. Coló·N. Van Giai
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Abstract

Zero-range effective interactions are commonly used in nuclear physics to describe a many-body system in the mean-field framework. If they are employed in beyond- mean-field models, an artificial ultraviolet divergence is generated by the zero-range of the interaction. We analyze this problem in symmetric nuclear matter with the t0-t3 Skyrme model. In this case, the second-order energy correction diverges linearly with the momentum cutoff. After that, we extend the work to the case of nuclear matter with the full Skyrme interaction. A strong divergence related to the velocity-dependent terms of the interaction is obtained. Moreover, a global fit can be simultaneously performed for both symmetric and nuclear matter with different neutron-to-proton ratios. These results pave the way for applications to finite nuclei in the framework of beyond mean-field theories.

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K. Moghrabi, M. Grasso, X. Roca-Maza, G. Coló, N. Van Giai. 2013-04-18. A beyond-mean-field example with zero-range effective interactions in infinite nuclear matter. https://doi.org/10.1051/epjconf%2F20123806002

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