- th / 9 70 40 36 v 1 1 7 A pr 1 99 7 Interfering Doorway States and Giant Resonances . I . Resonance Spectrum and Multipole Strengths
نویسندگان
چکیده
A phenomenological schematic model of multipole giant resonances (GR) is considered which treats the external interaction via common decay channels on the same footing as the coherent part of the internal residual interaction. The damping due to the coupling to the sea of complicated states is neglected. As a result, the formation of GR is governed by the interplay and competition of two kinds of collectivity, the internal and the external one. The mixing of the doorway components of a GR due to the external interaction influences significantly their multipole strengths, widths and positions in energy. In particular, a narrow resonance state with an appreciable multipole strength is formed when the doorway components strongly overlap.
منابع مشابه
ar X iv : n uc l - th / 9 70 40 38 v 1 1 7 A pr 1 99 7 Interfering Doorway States and Giant Resonances . II . Transition Strengths
The mixing of the doorway components of a giant resonance (GR) due to the interaction via common decay channels influences significantly the distribution of the multipole strength and the energy spectrum of the decay products of the GR. The concept of the partial widths of a GR becomes ambiguous when the mixing is strong. In this case, the partial widths determined in terms of the K-and S-matri...
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