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Ground state particle-particle correlations and double beta decay

A. A. Raduta·P. Sarriguren·Amand Faessler·E. Moya de Guerra
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Abstract

A self-consistent formalism for the double beta decay of Fermi type is provided. The particle-particle channel of the two-body interaction is considered first in the mean field equations and then in the QRPA. The resulting approach is called the QRPA with a self-consistent mean field (QRPASMF). The mode provided by QRPASMF, does not collapse for any strength of the particle-particle interaction. The transition amplitude for double beta decay is almost insensitive to the variation of the particle-particle interaction. Comparing it with the result of the standard pnQRPA, it is smaller by a factor 6. The prediction for transition amplitude agrees quite well with the exact result. The present approach is the only one which produces a strong decrease of the amplitude and at the same time does not alter the stability of the ground state.

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A. A. Raduta, P. Sarriguren, Amand Faessler, E. Moya de Guerra. 2001-04-27. Ground state particle-particle correlations and double beta decay. https://doi.org/10.1006/aphy.2001.6183

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