Well-developed deformation in 42Si

S. Takeuchi; M. Matsushita; N. Aoi; P. Doornenbal; K. Li; T. Motobayashi; H. Scheit; D. Steppenbeck; H. Wang; H. Baba; D. Bazin; L. Càceres; H. Crawford; P. Fallon; R. Gernhäuser; J. Gibelin; S. Go; S. Grévy; C. Hinke; C. R. Hoffman; R. Hughes; E. Ideguchi; D. Jenkins; N. Kobayashi; Y. Kondo; R. Krücken; T. Le Bleis; J. Lee; G. Lee; A. Matta; S. Michimasa; T. Nakamura; S. Ota; M. Petri; T. Sako; H. Sakurai; S. Shimoura; K. Steiger; K. Takahashi; M. Takechi; Y. Togano; R. Winkler; K. Yoneda

doi:10.1103/physrevlett.109.182501

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arXiv · 1207.6191

Well-developed deformation in 42Si

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Abstract

Excited states in 38,40,42Si nuclei have been studied via in-beam gamma-ray spectroscopy with multi-nucleon removal reactions. Intense radioactive beams of 40S and 44S provided at the new facility of the RIKEN Radioactive Isotope Beam Factory enabled gamma-gamma coincidence measurements. A prominent gamma line observed with an energy of 742(8) keV in 42Si confirms the 2+ state reported in an earlier study. Among the gamma lines observed in coincidence with the 2+ -> 0+ transition, the most probable candidate for the transition from the yrast 4+ state was identified, leading to a 4+_1 energy of 2173(14) keV. The energy ratio of 2.93(5) between the 2+_1 and 4+_1 states indicates well-developed deformation in 42Si at N=28 and Z=14. Also for 38,40Si energy ratios with values of 2.09(5) and 2.56(5) were obtained. Together with the ratio for 42Si, the results show a rapid deformation development of Si isotopes from N=24 to N=28.

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S. Takeuchi, M. Matsushita, N. Aoi, P. Doornenbal, K. Li, T. Motobayashi, H. Scheit, D. Steppenbeck, H. Wang, H. Baba, D. Bazin, L. Càceres, H. Crawford, P. Fallon, R. Gernhäuser, J. Gibelin, S. Go, S. Grévy, C. Hinke, C. R. Hoffman, R. Hughes, E. Ideguchi, D. Jenkins, N. Kobayashi, Y. Kondo, R. Krücken, T. Le Bleis, J. Lee, G. Lee, A. Matta, S. Michimasa, T. Nakamura, S. Ota, M. Petri, T. Sako, H. Sakurai, S. Shimoura, K. Steiger, K. Takahashi, M. Takechi, Y. Togano, R. Winkler, K. Yoneda. 2012-07-26. Well-developed deformation in 42Si. https://doi.org/10.1103/physrevlett.109.182501

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