High-spin structure in 169W and 170W

doi:10.1016/0375-9474(85)90345-8

Nuclear Physics A

Volume 440, Issue 2, 8 July 1985, Pages 366-396

https://doi.org/10.1016/0375-9474(85)90345-8 Get rights and content

Abstract

High-spin states in ^{169, 170}W have been populated in $^{154} Gd (^{20} Ne, x n)$ reactions. In-beam γ-ray spectroscopic techniques with multi-detector set-ups, multiplicity filters and an anti-Compton shield have been used. Levels up to about spin 30 (tentatively up to 36) in ¹⁷⁰W and up to $572$ (tentatively up to $612$ ) in ¹⁶⁹W have been identified. The data are interpreted within the framework of a pairing-selfconsistent cranking model. The nuclear shape evolution with increasing spin is studied theoretically within a configuration-controlled shell correction approach and also pairing effects are studied. The behaviour of the yrast states around 28⁺ in ¹⁷⁰W can be related in a model-dependent way to a reduction of the neutron-pairing correlations.

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^∗: Present address: Hahn-Meitner Institut für Kernforschung, D-1000 Berlin 39, West Germany.

^∗∗: Present address: Tata Institute of Fundamental Research, Bombay, India.

^∗∗∗: Present address: Institutte of Physics, University of Oslo, Oslo, Norway.

^∗∗∗∗: on leave from Institute of Nuclear Physics, Krakow, Poland.

^‡: Present address: Institut für Kernphysik, KFA Jülich, D-5170 Jülich, West Germany.

^‡‡: Present address: Nuclear chemistry Division, Lawrence Livermore National Laboratory, CA 94550, USA.

^‡‡‡: On leave of absence from Institute of Physics, Technical University of Warsaw, Warsaw, Poland.

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High-spin structure in 169W and 170W

Abstract

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High-spin structure in ¹⁶⁹W and ¹⁷⁰W