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First Measurement of Collectivity of Coexisting Shapes based on Type II Shell Evolution: The Case of $^{96}$Zr

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 نشر من قبل Christoph Kremer
 تاريخ النشر 2016
  مجال البحث
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Background: Type II shell evolution has recently been identified as a microscopic cause for nuclear shape coexistence. Purpose: Establish a low-lying rotational band in 96-Zr. Methods: High-resolution inelastic electron scattering and a relative analysis of transition strengths are used. Results: The B(E2; 0_1^+ -> 2_2^+) value is measured and electromagnetic decay strengths of the secdond 2^+ state are deduced. Conclusions: Shape coexistence is established for 96-Zr. Type II shell evolution provides a systematic and quantitative mechanism to understand deformation at low excitation energies.


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