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Measurement of excited states in 40Si and evidence for weakening of the N=28 shell gap

C. M. Campbell·N. Aoi·D. Bazin·M. D. Bowen·B. A. Brown·J. M. Cook·D. -C. Dinca·A. Gade·T. Glasmacher·M. Horoi·S. Kanno·T. Motobayashi·W. F. Mueller·H. Sakurai·K. Starosta·H. Suzuki·S. Takeuchi·J. R. Terry·K. Yoneda·H. Zwahlen
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Abstract

Excited states in 40Si have been established by detecting gamma-rays coincident with inelastic scattering and nucleon removal reactions on a liquid hydrogen target. The low excitation energy, 986(5) keV, of the 2+[1] state provides evidence of a weakening in the N=28 shell closure in a neutron-rich nucleus devoid of deformation-driving proton collectivity.

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C. M. Campbell, N. Aoi, D. Bazin, M. D. Bowen, B. A. Brown, J. M. Cook, D. -C. Dinca, A. Gade, T. Glasmacher, M. Horoi, S. Kanno, T. Motobayashi, W. F. Mueller, H. Sakurai, K. Starosta, H. Suzuki, S. Takeuchi, J. R. Terry, K. Yoneda, H. Zwahlen. 2006-08-15. Measurement of excited states in 40Si and evidence for weakening of the N=28 shell gap. https://doi.org/10.1103/physrevlett.97.112501

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