Role of Deformation in the Intrusion of the <span class="aps-inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msub><mrow><mi>h</mi></mrow><mrow><mfrac><mrow><mn>9</mn></mrow><mrow><mn>2</mn></mrow></mfrac></mrow></msub></mrow></math></span> Levels below the <span class="aps-inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>Z</mi><mo>=</mo><mn>82</mn><mn></mn></math></span> Proton Shell

J. A. Bounds; C. R. Bingham; P. Juncar; H. K. Carter; G. A. Leander; R. L. Mlekodaj; E. H. Spejewski; W. M. Fairbank, Jr

doi:10.1103/PhysRevLett.55.2269

Role of Deformation in the Intrusion of the $h_{\frac{9}{2}}$ Levels below the $Z = 82$ Proton Shell

J. A. Bounds, C. R. Bingham, P. Juncar, H. K. Carter, G. A. Leander, R. L. Mlekodaj, E. H. Spejewski, and W. M. Fairbank, Jr.

Phys. Rev. Lett. 55, 2269 – Published 18 November 1985

Abstract

The hyperfine structure and isotope shifts of ${}^{189, 191, 193}{Tl}^{m}$ and ${}^{193}{Tl}$ have been observed by means of collinear atom beam laser spectroscopy. Deduced deformations for the ${\frac{9}{2}}^{-}$ isomers are larger than for the ${\frac{1}{2}}^{+}$ ground states and increase with decreasing neutron number. This explains a strong neutron-number dependence of the odd-proton energy levels in these nuclei near the $Z = 82$ shell closure. Despite different deformations, rotational properties are nearly identical in ${}^{185 - 199}{Tl}$ . Microscopic theory ascribes this to a systematic balance between changing deformation and neutron pairing.

Received 26 April 1985

DOI:https://doi.org/10.1103/PhysRevLett.55.2269

Authors & Affiliations

J. A. Bounds, C. R. Bingham, and P. Juncar^*

The University of Tennessee, Knoxville, Tennessee 37996

H. K. Carter, G. A. Leander, R. L. Mlekodaj, and E. H. Spejewski^†

UNISOR, Oak Ridge Associated Universities, Oak Ridge, Tennessee 37831

W. M. Fairbank, Jr.^‡

Vanderbilt University, Nashville, Tennessee 37235

^*Present address: Laboratoire Aimè Cotton, Centre National de la Recherche Scientifique II, F-91405, Orsay Cedex, France.
^†Present address: Energy/SDS, Oak Ridge Associated Universities, Oak Ridge, Tenn. 37831.
^‡Present address: Colorado State University, Ft. Collins, Colo. 80523.