Skip to main content
SpringerLink
Log in

New β-delayed proton decays in the rare-earth region near the proton drip line

  • Published:
Science in China Series A: Mathematics Aims and scope Submit manuscript

Abstract

The β-delayed proton precursors125Nd128Pm129Sm,137Gd and139Dy near the proton drip line were produced by the irradiation of92Mo,96Ru and106Cd with an36Ar beam, and conclusively identified for the first time by using proton-gamma coincidence in combination with a He-jet tape transport system. Their half-lives were determined to be 0.60(15)s,1.0(3)s,O.55(10)s,2.2(2)s and 0.6 (2)s, respectively. The measured energy spectra of β-delayed protons and estimated proton branching ratios to the final states in “daughter” nuclei for the precursors125Nd,129Sm,137Gd and139Dy, as well as the previously reported ones for the precursors135Gd and121Ce, were fitted by a statistical model calculation. The ground-state spins and parities of121Ce,125Nd,129Sm,139Gd,137Gd and139Dy were then assigned as 5/2±,5/2±, 1/2± (or 3/2+), 5/2+,7/2+- and 7/2, respectively. The consistency between the experimental spin-parity assignment and the predicted Nilsson diagrams indirectly indicates that the ground states of121Ce,125Nd,129Sm,135Gd,137Gd and139Dy are highly deformed with β2, - 0.3.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

References

  1. Hofmann, S., Proton radioactivity, Radiochimica Acta, 1995, 70/71: 93.

    Google Scholar 

  2. Mdler, P., Nix, J.R., Myers, W.D. et al., Nuclear ground-state masses and deformations, At. Data Nucl. Data Tables, 1995, 59: 185.

    Article  Google Scholar 

  3. Xu, S.W., Xie, Y.X., Li, Z.K. et al., New β-delayed proton precursor135Gd, Z. Phys. A, 1996, 356: 227.

    Article  Google Scholar 

  4. Xu, S. W., Xie, Y.X., Li, Z.K. et al., Synthesis and study of the new β-delayed proton precursor135Gd near the proton drip-line, Science in China, Ser. A (in Chinese), 1997, 27(5): 434.

    Google Scholar 

  5. Li, Z.K., Xu, S.W., Xie, Y.X. et al., New β-delayed proton precursor121Ce, Phys. Rev. C. 1997, 56: 1157.

    Article  Google Scholar 

  6. Xu, S.W., Li, Z.K., Xie, Y.X. et al., New edelayed proton precursor121Ce mear the proton drip-line, Science in China, Ser. A, 1998, 41(11): 1223.

    Article  Google Scholar 

  7. Larsson, P.O., Batisch, T., Kirchner, R. et a1., Direct proton decay of 0.56-s 147Tm and search for this decay mode among very neutron-deficient isotopes with 53 ≤ Z ≤ 67, Z. Phys. A, 1983, 314: 9.

    Article  Google Scholar 

  8. Livingston, K., Woods, P.J., Davis, N.J. et al., Searches for proton radioactivity in oddZ drip-line nuclei fromZ = 61 to 67, Phys. Rev. C, 1993, 48: 3113.

    Article  Google Scholar 

  9. Beraud, R., Emsallem, A., he, J. et al., Nuclear spectroscopy of exotic nuclei with the SARA/IGISOL facility, Third INRP3-RMEN Sympmium on Heavy Ion Collisions, Tokyo, Japan, 1994, 102; Workshop IGISOL-6, Dubna, Russia, 1997, 59.

  10. Iimura, H., Katakura, J., Kitao, K. et al., Nuclear data sheets forA = 124, Nucl. Data Sheets, 1997, 80: 895.

    Article  Google Scholar 

  11. Homh(j, P., Wilsky, K., Hansen, P.G. et al., Beta-delayed proton emission from heavy nuclei, Nucl. Phys. A, 1972. 187: 609.

    Article  Google Scholar 

  12. Hardy, J.C., Towards a reliable method for calculating average radiation widths in exotic nuclei, Phya. Lett. B, 1982, 109: 242.

    Article  Google Scholar 

  13. James, A.N., Morrison, T.P., Nolan, P.J. et al., A catalogue of gamma-ray spectra for 25 nuclei near129Pr, Nuclear Structure Appendix, Daresbury Annual Report, 1985, 86: 103.

    Google Scholar 

  14. Mwrop, R., Campbell, M., Gelletly, W. et al., The deformation systematics of the light even-even neodymium isotopes, Nucl. Phys. A, 1989, 499: 565.

    Article  Google Scholar 

  15. Paul, E.S., Davis, S., Vaaka, P. et al., Rolate and oblate rotational bands in139Sm, J. Physics (London), G, 1993, 19: 861.

    Google Scholar 

  16. Nitschke, J.M., Cable, M.D., Zeite. W.D., New beta-delayed proton emitters in the lanthanide region, Z. Phys. A, 1983, 312: 265.

    Article  Google Scholar 

  17. Takehashi, K., Yamada, M., Kondoh, F., Beta-decay half-lives calculated on the gross theory, At. Data Nuel. Data Tables, 1973, 12: 101.

    Article  Google Scholar 

  18. Horiguchi, T., Tachibana, T., Katakura, J., Charts of the Nuclides, 1996, Japan Atomic Energy Research Institute, 1996.

  19. Hirsch, M., Staudt, A., Muto, K. et al., Microscopic predictions of β+/EC-decay half-lives, At. Data Nucl. Data Tables, 1993, 53: 165.

    Article  Google Scholar 

  20. Möller, P., Nix, J.R., Kratz, K. L., Nuclear properties for astrophysical and radioactive-ion-beam application, At. Data Nucl. Data Tables, 1997, 66: 131.

    Article  Google Scholar 

  21. Lister, C.J., Varley, B.J., Moscmp, R. et al., Deformation of wxy light rare-earth nuclei, Phys. Rev. Lett., 1985, 55: 810.

    Article  Google Scholar 

  22. Winn, W.G., Gutbmd, H.H., Blann, M., Predicted limits for production of new proton-rich nuclei by a heavy-ion cornpound-nucleus mechanism, Nucl. Phya. A, 1972, 188: 423.

    Article  Google Scholar 

  23. Arseniev, D.A., Sobiczewski, A., Solview, V.G., Ground and excited state deformations in the 50Z, N 82 region, Nucl. Phys. A, 1969, 126: 15.

    Article  Google Scholar 

  24. Bengtsson, T., Ragnarason, I., Rotational bands and particle-hole excitations at very high spin, Nucl. Phys. A, 1985, 436: 14.

    Article  Google Scholar 

  25. Audi, G., Bersillon, O., Blachot, J. et al., The NUBASE evaluation of nuclear and decay properties, Nucl. Phys. A, 1997, 624: 1.

    Article  Google Scholar 

Download references

Author information

Authors and Affiliations

  1. Institute of Modem Physics, Chinese Academy of Sciences, 730000, Lanzhou, China

    Shuwei Xu, Zhankui Li, Yuanxiang Xie, Yong Yu, Qiangyan Pan, Chunfang Wang, Jianping Xing, Ruichang Ma, Yuanxiu Ge & Tianmei Zhang

Authors
  1. Shuwei Xu
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Zhankui Li
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Yuanxiang Xie
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Yong Yu
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Qiangyan Pan
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. Chunfang Wang
    View author publications

    You can also search for this author in PubMed Google Scholar

  7. Jianping Xing
    View author publications

    You can also search for this author in PubMed Google Scholar

  8. Ruichang Ma
    View author publications

    You can also search for this author in PubMed Google Scholar

  9. Yuanxiu Ge
    View author publications

    You can also search for this author in PubMed Google Scholar

  10. Tianmei Zhang
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Shuwei Xu.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Xu, S., Li, Z., Xie, Y. et al. New β-delayed proton decays in the rare-earth region near the proton drip line. Sci. China Ser. A-Math. 43, 885–891 (2000). https://doi.org/10.1007/BF02884188

Download citation

  • Received:

  • Issue Date:

  • DOI: https://doi.org/10.1007/BF02884188

Keywords

Search

Navigation