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Title: Observation of β-delayed two-proton emission in the decay of 22Si

Abstract

The decay of the lightest nucleus with Tz=-3, 22Si, was studied by a silicon array. A charged-particle group at 5600 (70) keV in the decay-energy spectrum was identified experimentally as β-delayed two-proton emission from the isobaric analog state (IAS) of 22Al. Experimental results of the IAS fed by a superallowed Fermi transition were compared with our large-scale shell-model calculations. The ground-state mass of 22Si was obtained indirectly in the experiment for the first time. Two-proton separation energy for 22Si is deduced to be -108 (125) keV, which indicates that it is a very marginal candidate for two-proton ground-state emission.

Authors:
 [1];  [2];  [3];  [4];  [4];  [5];  [6];  [7];  [8];  [9];  [3];  [6];  [7];  [3];  [6];  [7];  [6];  [6];  [4];  [4] more »;  [6];  [6];  [6];  [6];  [4];  [4];  [4];  [4];  [4];  [3];  [3];  [3];  [3];  [4];  [4];  [4];  [4];  [4];  [4];  [4];  [4];  [4];  [6];  [4];  [4];  [3] « less
  1. China Institute of Atomic Energy, Beijing (China); Univ. of Hong Kong (China). Dept. of Physics
  2. China Institute of Atomic Energy, Beijing (China); Guangxi Normal University, Guilin (China). College of Physics and Technology
  3. China Institute of Atomic Energy, Beijing (China)
  4. Chinese Academy of Sciences, Lanzhou (China). Institute of Modern Physics
  5. Univ. of Hong Kong (China). Dept. of Physics
  6. Shanghai Institute of Applied Physics, Chinese Academy of Sciences (China)
  7. Peking University, Beijing (China). School of Physic and State Key Laboratory of Nuclear Physics and Technology
  8. CENBG, CNRS/IN2P3 and Universite de Bordeaux, Chemin du Solarium (France)
  9. Sun Yat-Sen University, Zhuhai (China). Sino-French Institute of Nuclear Engineering and Technology
Publication Date:
Research Org.:
Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
1423615
Grant/Contract Number:
AC02-05CH11231
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Physics Letters. Section B
Additional Journal Information:
Journal Volume: 766; Journal Issue: C; Journal ID: ISSN 0370-2693
Publisher:
Elsevier
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS

Citation Formats

Xu, X. X., Lin, C. J., Sun, L. J., Wang, J. S., Lam, Y. H., Lee, J., Fang, D. Q., Li, Z. H., Smirnova, N. A., Yuan, C. X., Yang, L., Wang, Y. T., Li, J., Ma, N. R., Wang, K., Zang, H. L., Wang, H. W., Li, C., Liu, M. L., Wang, J. G., Shi, C. Z., Nie, M. W., Li, X. F., Li, H., Ma, J. B., Ma, P., Jin, S. L., Huang, M. R., Bai, Z., Yang, F., Jia, H. M., Liu, Z. H., Wang, D. X., Yang, Y. Y., Zhou, Y. J., Ma, W. H., Chen, J., Hu, Z. G., Wang, M., Zhang, Y. H., Ma, X. W., Zhou, X. H., Ma, Y. G., Xu, H. S., Xiao, G. Q., and Zhang, H. Q.. Observation of β-delayed two-proton emission in the decay of 22Si. United States: N. p., 2017. Web. doi:10.1016/j.physletb.2017.01.028.
Xu, X. X., Lin, C. J., Sun, L. J., Wang, J. S., Lam, Y. H., Lee, J., Fang, D. Q., Li, Z. H., Smirnova, N. A., Yuan, C. X., Yang, L., Wang, Y. T., Li, J., Ma, N. R., Wang, K., Zang, H. L., Wang, H. W., Li, C., Liu, M. L., Wang, J. G., Shi, C. Z., Nie, M. W., Li, X. F., Li, H., Ma, J. B., Ma, P., Jin, S. L., Huang, M. R., Bai, Z., Yang, F., Jia, H. M., Liu, Z. H., Wang, D. X., Yang, Y. Y., Zhou, Y. J., Ma, W. H., Chen, J., Hu, Z. G., Wang, M., Zhang, Y. H., Ma, X. W., Zhou, X. H., Ma, Y. G., Xu, H. S., Xiao, G. Q., & Zhang, H. Q.. Observation of β-delayed two-proton emission in the decay of 22Si. United States. doi:10.1016/j.physletb.2017.01.028.
Xu, X. X., Lin, C. J., Sun, L. J., Wang, J. S., Lam, Y. H., Lee, J., Fang, D. Q., Li, Z. H., Smirnova, N. A., Yuan, C. X., Yang, L., Wang, Y. T., Li, J., Ma, N. R., Wang, K., Zang, H. L., Wang, H. W., Li, C., Liu, M. L., Wang, J. G., Shi, C. Z., Nie, M. W., Li, X. F., Li, H., Ma, J. B., Ma, P., Jin, S. L., Huang, M. R., Bai, Z., Yang, F., Jia, H. M., Liu, Z. H., Wang, D. X., Yang, Y. Y., Zhou, Y. J., Ma, W. H., Chen, J., Hu, Z. G., Wang, M., Zhang, Y. H., Ma, X. W., Zhou, X. H., Ma, Y. G., Xu, H. S., Xiao, G. Q., and Zhang, H. Q.. Thu . "Observation of β-delayed two-proton emission in the decay of 22Si". United States. doi:10.1016/j.physletb.2017.01.028. https://www.osti.gov/servlets/purl/1423615.
@article{osti_1423615,
title = {Observation of β-delayed two-proton emission in the decay of 22Si},
author = {Xu, X. X. and Lin, C. J. and Sun, L. J. and Wang, J. S. and Lam, Y. H. and Lee, J. and Fang, D. Q. and Li, Z. H. and Smirnova, N. A. and Yuan, C. X. and Yang, L. and Wang, Y. T. and Li, J. and Ma, N. R. and Wang, K. and Zang, H. L. and Wang, H. W. and Li, C. and Liu, M. L. and Wang, J. G. and Shi, C. Z. and Nie, M. W. and Li, X. F. and Li, H. and Ma, J. B. and Ma, P. and Jin, S. L. and Huang, M. R. and Bai, Z. and Yang, F. and Jia, H. M. and Liu, Z. H. and Wang, D. X. and Yang, Y. Y. and Zhou, Y. J. and Ma, W. H. and Chen, J. and Hu, Z. G. and Wang, M. and Zhang, Y. H. and Ma, X. W. and Zhou, X. H. and Ma, Y. G. and Xu, H. S. and Xiao, G. Q. and Zhang, H. Q.},
abstractNote = {The decay of the lightest nucleus with Tz=-3, 22Si, was studied by a silicon array. A charged-particle group at 5600 (70) keV in the decay-energy spectrum was identified experimentally as β-delayed two-proton emission from the isobaric analog state (IAS) of 22Al. Experimental results of the IAS fed by a superallowed Fermi transition were compared with our large-scale shell-model calculations. The ground-state mass of 22Si was obtained indirectly in the experiment for the first time. Two-proton separation energy for 22Si is deduced to be -108 (125) keV, which indicates that it is a very marginal candidate for two-proton ground-state emission.},
doi = {10.1016/j.physletb.2017.01.028},
journal = {Physics Letters. Section B},
number = C,
volume = 766,
place = {United States},
year = {Thu Jan 19 00:00:00 EST 2017},
month = {Thu Jan 19 00:00:00 EST 2017}
}

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