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arXiv · 0708.3007

On the measurement of B(E2, 0+ -> 2+) using intermediate-energy Coulomb excitation

F. Delaunay·F. M. Nunes
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Abstract

Coulomb excitation is a standard method used to extract quadrupole excitation strengths of even-even nuclei. In typical analyses the reaction is assumed to be one-step, Coulomb only, and is treated within a semi-classical model. In this work, fully-quantal coupled-channel calculations are performed for three test cases in order to determine the importance of multi-step effects, nuclear contributions, feeding from other states and corrections to the semi-classical approximation. We study the excitation of 30S, 58Ni and 78Kr on 197Au at ~ 50 AMeV. We find that nuclear effects may contribute more than 10% and that feeding contributions can be larger than 15%. These corrections do not alter significantly the published B(E2) values, however an additional theoretical error of up to 13% should be added to the experimental uncertainty if the semi-classical model is used. This theoretical error is reduced to less than 7% when performing a quantal coupled-channel analysis.

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F. Delaunay, F. M. Nunes. 2007-08-22. On the measurement of B(E2, 0+ -> 2+) using intermediate-energy Coulomb excitation. https://doi.org/10.1088/0954-3899%2F34%2F10%2F010

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