Elsevier

Nuclear Physics A

Volume 378, Issue 1, 5 April 1982, Pages 141-158
Nuclear Physics A

Measurement of the linear polarization of continuum gamma rays from (32S, xn) reactions to prolate and oblate rare-earth nuclei

https://doi.org/10.1016/0375-9474(82)90387-6Get rights and content

Abstract

We describe the techniques and report the results of a measurement of the linear polarization, Pγ of continuum γ-rays from Er and Dy nuclei produced in (32S, xn) reactions on 130Te and 124Sn targets. For the prolate 156–158Er isotopes we find Pγ ≈ 0.35 in the γ-ray energy range if0.3 MeV ≦ Eγ ≦ 1.5 MeV, thus confirming the E2 nature of the unresolved yrast cascades in rotational nuclei. In contrast, the rather small polarization Pγ ≈ 0.05 for Eγ ≦ 1.0 MeV measured for the oblate 151,152Dy isotopes, and the shape of the spectrum of continuum γ-rays suggest a rather direct feeding of the yrast states by statistical cascades. For 1.0 MeV ≦ Eγ ≦ 1.5 MeV we find Pγ ≈ 0.3 indicating collective rotations of the Dy nuclei at spin I ≧ 40hz.shtsls;. Measurements of γ-ray angular distributions with a collimated NaI detector support these results. From the reduction of the Pγ, and A2 values of the γ-ray continuum in 156–158Er, compared to those measured for discrete E2 yrast transitions, we obtain estimates for the intensities of the M1 and statistical components in the continuum of these nuclei.

References (24)

  • B. Haas et al.

    Phys. Lett.

    (1979)
    B. Haas et al.

    Nucl. Phys.

    (1981)
  • O. Hausser et al.

    Phys. Rev. Lett.

    (1980)
  • J.C. Merdinger et al.

    Phys. Rev. Lett.

    (1979)
  • E. Grosse et al.

    Phys. Rev. Lett.

    (1973)
  • H. Hübel et al.

    Z. Phys.

    (1980)
  • R. Bass

    Phys. Lett.

    (1973)
  • S. Lunardi et al.
  • J.O. Newton et al.

    Phys. Rev. Lett.

    (1978)
    J.O. Newton et al.

    Nucl. Phys.

    (1980)
  • R.J. Liotta et al.

    Nucl. Phys.

    (1978)
  • K.S. Krane et al.

    Nucl. Data, sect.

    (1973)
  • R.M. Diamond et al.

    Ann. Rev. Nucl. Part. Sci.

    (1980)
  • B. Herskind
  • Cited by (12)

    • Nuclear Data Sheets for A = 152

      2013, Nuclear Data Sheets
    • Nuclear Data Sheets for A = 156

      2012, Nuclear Data Sheets
    • Nuclear Data Sheets for A = 151

      2009, Nuclear Data Sheets
    • Nuclear data sheets for A = 156

      2003, Nuclear Data Sheets
    View all citing articles on Scopus

    Permanent Address: Ludwig-Maximilians Universität, München, W.-Germany.

    ††

    University of Liverpool, United Kingdom.

    CNR, Strasbourg, France.

    ‡‡

    Université de Montréal, Canada.

    View full text