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Large enhancement of radiative strength for soft transisitons in the quasicontinuum

A. Voinov·E. Algin·U. Agvaanluvsan·T. Belgya·R. Chankova·M. Guttormsen·G. E. Mitchell·J. Rekstad·A. Schiller·S. Siem
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Abstract

Radiative strength functions (RSFs) for the 56,57-Fe nuclei below the separation energy are obtained from the 57-Fe(3-He,alpha gamma)56-Fe and 57-Fe(3-He,3-He' gamma)57-Fe reactions, respectively. An enhancement of more than a factor of ten over common theoretical models of the soft (E_gamma ~< 2 MeV) RSF for transitions in the quasicontinuum (several MeV above the yrast line) is observed. Two-step cascade intensities with soft primary transitions from the 56-Fe(n,2gamma)57-Fe reaction confirm the enhancement.

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A. Voinov, E. Algin, U. Agvaanluvsan, T. Belgya, R. Chankova, M. Guttormsen, G. E. Mitchell, J. Rekstad, A. Schiller, S. Siem. 2004-04-26. Large enhancement of radiative strength for soft transisitons in the quasicontinuum. https://doi.org/10.1103/physrevlett.93.142504

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