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arXiv · 2204.08852

Evolution of the $γ$-ray strength function in neodymium isotopes

M. Guttormsen·K. O. Ay·M. Ozgur·E. Algin·A. C. Larsen·F. L. Bello Garrote·H. C. Berg·L. Crespo Campo·T. Dahl-Jacobsen·F. W. Furmyr·D. Gjestvang·A. Görgen·T. W. Hagen·V. W. Ingeberg·B. V. Kheswa·I. K. B. Kullmann·M. Klintefjord·M. Markova·J. E. Midtbø·V. Modamio·W. Paulsen·L. G. Pedersen·T. Renstrøm·E. Sahin·S. Siem·G. M. Tveten·M. Wiedeking
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Abstract

The experimental gamma-ray strength functions (gamma-SFs) of 142,144-151Nd have been studied for gamma-ray energies up to the neutron separation energy. The results represent a unique set of gamma-SFs for an isotopic chain with increasing nuclear deformation. The data reveal how the low-energy enhancement, the scissors mode and the pygmy dipole resonance evolve with nuclear deformation and mass number. The data indicate that the mechanisms behind the low-energy enhancement and the scissors mode are decoupled from each other.

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M. Guttormsen, K. O. Ay, M. Ozgur, E. Algin, A. C. Larsen, F. L. Bello Garrote, H. C. Berg, L. Crespo Campo, T. Dahl-Jacobsen, F. W. Furmyr, D. Gjestvang, A. Görgen, T. W. Hagen, V. W. Ingeberg, B. V. Kheswa, I. K. B. Kullmann, M. Klintefjord, M. Markova, J. E. Midtbø, V. Modamio, W. Paulsen, L. G. Pedersen, T. Renstrøm, E. Sahin, S. Siem, G. M. Tveten, M. Wiedeking. 2022-09-23. Evolution of the $γ$-ray strength function in neodymium isotopes. https://doi.org/10.1103/physrevc.106.034314

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