Experimental study of the S 38 excited level scheme

Hoffman, C. R.; Lubna, R. S.; Rubino, E.; Tabor, S. L.; Auranen, K.; Bender, P. C.; Campbell, C. M.; Carpenter, M. P.; Chen, J.; Gott, M.; Greene, J. P.; Hoff, D. M.; Huang, T.; Iwasaki, H.; Kondev, F. G.; Lauritsen, T.; Longfellow, B.; Santamaria, C.; Seweryniak, D.; Tang, T. L.; Wilson, G. L.; Wu, J.; Zhu, S.

doi:10.1103/physrevc.107.064311

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Experimental study of the S 38 excited level scheme

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Abstract

Information on the 38 S level scheme was expanded through experimental work utilizing a fusion-evaporation reaction and in-beam γ-ray spectroscopy. Prompt γ-ray transitions were detected by the Gamma-Ray Energy Tracking Array (GRETINA) and recoiling 38 S residues were selected by the Fragment Mass Analyzer (FMA). Tools based on machine-learning techniques were developed and deployed for the first time in order to enhance the unique selection of 38S residues and identify any associated γ-ray transitions. The new level information, including the extension of the even-spin yrast sequence through J π =8( + ), was interpreted in terms of a basic single-particle picture as well shell-model calculations which incorporated the empirically derived FSU interaction. A comparison between the properties of the yrast states in the even-Z, N = 22 isotones from Z = 14 to 20, and for 36 Si– 38 S in particular, was also presented with an emphasis on the role and influence of the neutron 1 p 3/2 orbital on the structure in the region.

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20 ≤ A ≤ 38 73 NUCLEAR PHYSICS AND RADIATION PHYSICS Electromagnetic transitions electromagnetic transitions gamma ray spectroscopy machine learning nuclear structure & decays

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Hoffman, C. R., Lubna, R. S., Rubino, E., Tabor, S. L., Auranen, K., Bender, P. C., Campbell, C. M., Carpenter, M. P., Chen, J., Gott, M., Greene, J. P., Hoff, D. M., Huang, T., Iwasaki, H., Kondev, F. G., Lauritsen, T., Longfellow, B., Santamaria, C., Seweryniak, D., Tang, T. L., Wilson, G. L., Wu, J., Zhu, S.. 2023-06-20. Experimental study of the S 38 excited level scheme. https://doi.org/10.1103/physrevc.107.064311

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