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Fast nuclear rotation and octupole deformation

W. Urban·J. C. Bacelar·J. Nyberg
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Abstract

The 150Sm nucleus has been studied to high spins in a measurement of gamma radiation following the 136Xe(18O,4n)150Sm, compound-nucleus reaction at beam energy of 76 MeV. The measurement was performed at NBI Riso using the NORDBALL array. Alternating parity, s=+1 band in 150Sm has been observed up to spin I=22. This band is crossed by two aligned bands, corresponding to a reflection-symmetric shape. After the second crossing the s=+1 band ends abruptly, suggesting that the octupole shape vanishes in 150Sm above spin I=22, as predicted by calculations. Other explanations, assuming continuation of the s=+1 band past the two alignments are also discussed.

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W. Urban, J. C. Bacelar, J. Nyberg. 2001-04-11. Fast nuclear rotation and octupole deformation. https://arxiv.org/abs/nucl-th/0104036

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