Abstract
The recently discovered, extremely proton-rich nuclide \(^{18}\)Mg exhibits ground-state decay via two sequential two-proton (2p) emissions through the intermediate nucleus, \(^{16}\)Ne. This study investigates the structure and the initial 2p decay mechanism of \(^{18}\textrm{Mg}\) by examining the density and correlations of the valence protons using a three-body Gamow coupled-channel method. The results show that the ground state of \(^{18}\textrm{Mg}\) is significantly influenced by the continuum, resulting in a significant s-wave component. However, based on the current framework, this does not lead to a significant deviation in mirror symmetry in either the structure or spectroscopy of the \(^{18}\textrm{Mg}\)–\(^{18}\textrm{C}\) pair. Additionally, the time evolution analysis of the \(^{18}\textrm{Mg}\) ground state suggests a simultaneous 2p emission during the first step of decay. The observed nucleon–nucleon correlations align with those of the light-mass 2p emitters, indicating a consistent decay behavior within this nuclear region.
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Data availability
The data that support the findings of this study are openly available in Science Data Bank at https://cstr.cn/31253.11.sciencedb.j00186.00161 and https://www.doi.org/10.57760/sciencedb.j00186.00161
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All authors contributed to the study conception and design. Material preparation, data collection and analysis were performed by Long Zhou, Si-Min Wang and De-Qing Fang. The first draft of the manuscript was written by Long Zhou and all authors commented on previous versions of the manuscript. All authors read and approved the final manuscript.
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De-Qing Fang and Si-Min Wang are the editorial board members for Nuclear Science and Techniques and was not involved in the editorial review, or the decision to publish this article. All authors declare that there are no Conflict of interest.
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This work was supported by the National Key Research and Development Program (MOST 2022YFA1602303 and MOST 2023YFA1606404), the National Natural Science Foundation of China (Nos. 12347106, 2147101, 11925502, 11935001 and 11961141003), the Strategic Priority Research Program of Chinese Academy of Sciences (No. XDB34030000).
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Zhou, L., Fang, DQ., Wang, SM. et al. Structure and 2p decay mechanism of 18Mg. NUCL SCI TECH 35, 107 (2024). https://doi.org/10.1007/s41365-024-01479-1
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DOI: https://doi.org/10.1007/s41365-024-01479-1