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arXiv · 0908.2607

Three-body forces and the limit of oxygen isotopes

Takaharu Otsuka·Toshio Suzuki·Jason D. Holt·Achim Schwenk·Yoshinori Akaishi
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Abstract

The limit of neutron-rich nuclei, the neutron drip-line, evolves regularly from light to medium-mass nuclei except for a striking anomaly in the oxygen isotopes. This anomaly is not reproduced in shell-model calculations derived from microscopic two-nucleon forces. Here, we present the first microscopic explanation of the oxygen anomaly based on three-nucleon forces that have been established in few-body systems. This leads to repulsive contributions to the interactions among excess neutrons that change the location of the neutron drip-line from $^{28}$O to the experimentally observed $^{24}$O. Since the mechanism is robust and general, our findings impact the prediction of the most neutron-rich nuclei and the synthesis of heavy elements in neutron-rich environments.

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Takaharu Otsuka, Toshio Suzuki, Jason D. Holt, Achim Schwenk, Yoshinori Akaishi. 2010-06-19. Three-body forces and the limit of oxygen isotopes. https://doi.org/10.1103/physrevlett.105.032501

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