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arXiv · 1112.1231

Fragmentation of electric dipole strength in N=82 isotones

Mitsuru Tohyama·Takashi Nakatsukasa
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Abstract

Fragmentation of the dipole strength in the N=82 isotones 140Ce, 142Nd and 144Sm is calculated using the second random-phase approximation (SRPA). In comparison with the result of the random-phase approximation (RPA), the SRPA provides the additional damping of the giant dipole resonance and the redistribution of the low-energy dipole strength. Properties of the low-energy dipole states are significantly changed by the coupling to two-particle-two-hole (2p2h) states, which are also sensitive to the correlation among the 2p2h states. Comparison with available experimental data shows a reasonable agreement for the low-energy E1 strength distribution.

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Mitsuru Tohyama, Takashi Nakatsukasa. 2011-12-06. Fragmentation of electric dipole strength in N=82 isotones. https://doi.org/10.1103/physrevc.85.031302

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