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arXiv · 1710.09159

Phonon-particle coupling effects in odd-even mass differences of semi-magic nuclei

E. E. Saperstein·M. Baldo·S. S. Pankratov·S. V. Tolokonnikov
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Abstract

A method to evaluate the particle-phonon coupling (PC) corrections to the single-particle energies in semi-magic nuclei, based on a direct solving the Dyson equation with PC corrected mass operator, is used for finding the odd-even mass difference between 18 even Pb isotopes and their odd-proton neighbors. The Fayans energy density functional (EDF) DF3-a is used which gives rather high accuracy of the predictions for these mass differences already on the mean-field level, with the average deviation from the existing experimental data equal to 0.389 MeV. It is only a bit worse than the corresponding value of 0.333 MeV for the Skyrme EDF HFB-17 which belongs to a family of Skyrme EDFs with the highest overall accuracy in describing the nuclear masses. Account for the PC corrections induced by the low-laying phonons $2^+_1$ and $3^-_1$ significantly diminishes the deviation of the theory from the data till 0.218 MeV.

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E. E. Saperstein, M. Baldo, S. S. Pankratov, S. V. Tolokonnikov. 2017-10-25. Phonon-particle coupling effects in odd-even mass differences of semi-magic nuclei. https://doi.org/10.1134/s0021364017210032

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