Elsevier

Nuclear Physics A

Volume 607, Issue 2, 16 September 1996, Pages 178-234
Nuclear Physics A

Quadrupole collectivity and shapes of OsPt nuclei

https://doi.org/10.1016/0375-9474(96)00181-9Get rights and content

Abstract

E2 collective properties for the low-lying states in 186,188,190,192Os and 194Pt have been investigated experimentally by means of Coulomb excitation using 3.3–4.8 MeV/nucleon 40Ca, 58Ni, 136Xe and 208Pb beams. The deexcitation γ rays following Coulomb excitation were detected in coincidence with the scattered particles. Levels with excitation energies up to 3–4 MeV of the ground-state, γ and 4+ collective bands as well as excited 0+ states were populated in each nucleus studied. A semiclassical Coulomb-excitation least-squares search code GOSIA was used to extract E2 matrix elements from the measured γ-ray yields. For each nucleus studied, a unique and almost complete set of E2 matrix elements for the low-lying states has been determined, which includes both the magnitudes and signs of the transitional and diagonal matrix elements. The completeness of the set of measured E2 matrix elements makes it possible to determine the intrinsic quadrupole deformation for the low-lying states in these nuclei via a model-independent method. The results indicate clearly that the E2 properties for the low-lying states in these nuclei are correlated well using only the quadrupole collective degrees of freedom. The extracted E2 matrix elements are compared with the prediction of various collective models such as the asymmetric rigid rotor model, the γ-soft model of Leander, and the IBA-2 model. These particular models do not reproduce the data satisfactorily, however the general trends of the data are consistent with the descriptions of γ-soft type collective models through a prolate to oblate shape-transition region. That the enhanced B(E2) values between the I,quasi-Kπ = 4,4+ state and members of the I,quasi-Kπ = 2,2+ band are well reproduced by the γ-soft model is consistent with the interpretation of the I,quasi-Kπ = 4,4+ state being a two-phonon γ-vibration excitation.

References (88)

  • B. Harmatz

    Nucl. Data Sheets

    (1977)
  • D. Cline et al.

    Nucl. Inst. and Meth.

    (1970)
  • L.D. Tolsma

    Phys. Rev. C

    (1979)
  • R. Bijker et al.

    Nucl. Phys. A

    (1980)
  • A. Abragam et al.

    Phys. Rev.

    (1953)
  • R. Spanhoff et al.

    Phys. Rev. C

    (1978)
  • T. Yamazaki et al.

    Nucl. Phys. A

    (1973)
  • K.J. Hofstetter et al.

    Phys. Rev. C

    (1973)
  • S.W. Yates et al.

    Nucl. Phys. A

    (1974)
  • R. Spanhoff et al.

    Hyperfine Int.

    (1981)
  • M.V. Hoehn et al.

    Phys. Rev. C

    (1981)
  • C. Baktash et al.

    Phys. Rev. C

    (1980)
  • S.W. Yates et al.

    Nucl. Phys. A

    (1974)
  • M.R. Schmorak

    Nucl. Data Sheets

    (1973)
  • A. Pakkanen et al.

    Physica Fennica

    (1973)
  • R.J. Gehrke

    Nucl. Phys. A

    (1973)
  • E.W. Kleppinger et al.

    Phys. Rev. C

    (1983)
  • S.W. Yates, private communication...
  • H.J. Wollersheim, private communication...
  • N.R. Johnson et al.

    Phys. Rev. C

    (1977)
  • J.E. Glenn et al.

    Phys. Rev.

    (1969)
  • A.L. Allsop et al.

    J. Phys. G

    (1982)
  • P.D. Bond et al.

    Nucl. Phys. A

    (1971)
  • K.S. Krane et al.

    Phys. Rev. C

    (1971)
  • H. Helppi et al.

    Nucl. Phys. A

    (1974)
  • K. Kumar et al.

    Nucl. Phys. A

    (1968)
  • G. Leander, private communication...G. Leander

    Nucl. Phys. A

    (1976)
  • F.T. Baker et al.

    Phys. Rev. Lett.

    (1976)
  • R.D. Bagnell et al.

    Phys. Rev. C

    (1979)
  • R.M. Lieder et al.

    Nucl. Phys. A

    (1982)
  • G.D. Dracoulis et al.

    Nucl. Phys. A

    (1982)
  • G. Dracoulis et al.

    Phys. Rev. Lett.

    (1980)
  • M.H. Macfarlane et al.

    Technical Report ANL-76-11 Rev. 1, Argonne Nat. Lab.

    (1978)
  • C.Y. Wu et al.

    Bull. Amer. Phys. Soc.

    (1984)
  • D. Cline
  • T. Czosnyka et al.

    Nucl. Phys. A

    (1986)
  • J.E. Glenn et al.

    Phys. Rev. Lett.

    (1968)
  • R.J. Pryor et al.

    Phys. Rev. C

    (1970)
  • S.A. Lane et al.

    Phys. Rev. C

    (1972)
  • J.K. Sprinkle
  • A. Winther et al.
  • L. Hasselgren et al.

    Interacting Bose-Fermi Systems in Nuclei

  • D. Cline
  • T. Czosnyka, D. Cline and C.Y. Wu, to be...
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    1

    Permanent address: Heavy Ion Laboratory, University of Warsaw, Warsaw, Poland.

    2

    Permanent address: Institute of Radiation Science, Uppsala University, S-75121 Uppsala, Sweden.

    3

    Present address: Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.

    4

    Permanent address: Hahn-Meitner Institute, D-14091 Berlin 39, Germany.

    5

    Present address: Paul Scherrer Institute, F1 Division, CH-5232 Villigen PSI, Switzerland.

    6

    Permanent address: Department of Physics, University of Manchester, Manchester, UK.

    7

    Present address: CSIRO Division of Exploration Geoscience, N. Ryde, Australia.

    8

    Permanent address: University of Warsaw, Warsaw, Poland.

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