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Status of delayed-neutron precursor data: Half-lives and neutron emission probabilities

B. Pfeiffer·K. -L. Kratz·P. Moeller
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Abstract

We present in this paper a compilation of the present status of experimental delayed-neutron precursor data; i.e. beta-decay half-lives (T_1/2) and neutron emission probabilities (P_n) in the fission-product region (27 <= Z <= 57). These data are compared to two model predictions of substantially different sophistication: (i) an update of the empirical Kratz-Herrmann formula (KHF), and (ii) a unified macroscopic-microscopic model within the quasi-particle random-phase approximation (QRPA). Both models are also used to calculate so far unknown T_1/2 and P_n values up to Z=63. A number of possible refinements in the microscopic calculations are suggested to further improve the nuclear-physics foundation of these data for reactor and astrophysical applications.

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B. Pfeiffer, K. -L. Kratz, P. Moeller. 2001-06-22. Status of delayed-neutron precursor data: Half-lives and neutron emission probabilities. https://arxiv.org/abs/nucl-ex/0106020

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