A highly deformed band in {sup 136}Pm and the anomalous h{sub 11/2} proton crossing in the A {approx} 135 superdeformed region
The dynamical moments of inertia (J{sup (2)}) of superdeformed (SD) bands in the A{approximately}150 Gd-Dy and A{approximately}190 Hg-Pb regions are fairly well reproduced by standard cranking calculations. However, for the super or highly deformed A-135 Ce-Nd-Sm region, this is not true at all, and has presented a theoretical puzzle for some time. Several theoretical {open_quote}fixes{close_quotes} and suggestions in terms of quenched proton pairing and a strong residual proton-neutron interaction have been proposed. We have performed several experiments on the odd-odd nucleus {sup 136}Pm to help shed light on this problem. The first took place at the Holifield Heavy Ion Research Facility at Oak Ridge and used the {sup 106}Pd({sup 34}S,p3n) reaction at 165 MeV. High resolution {gamma}-ray information was collected using 18 Compton suppressed Ge detectors which replaced elements within the Spin Spectrometer. Total energy and fold information was recorded by the remaining 52 NaI elements of the Spin Spectrometer. In addition, because charged particle emission competes on an equal footing with neutron evaporation in this mass region, the Washington University Dwarf Ball was used to detect the charged particles in coincidence with {gamma}-rays. Another experiment was performed at Florida State University using the Superconducting Linear Accelerator Facility and the {sup 108}Pd({sup 32}S,p3n) reaction at 145 MeV. Gamma-rays were detected by the Pittsburgh-FSU array consisting of 9 Compton suppressed Ge detectors plus a 28 element bismuth germanate (BGO) sum energy/multiplicity ball. In both experiments a rotational band has been observed in {sup 136}Pm possessing an enhanced moment of inertia consistent with other highly deformed structures in this region.
- OSTI ID:
- 386914
- Report Number(s):
- CONF-931044-; ISSN 0003-0503; TRN: 96:026849
- Journal Information:
- Bulletin of the American Physical Society, Vol. 38, Issue 9; Conference: Fall meeting of the Division of Nuclear Physics of the American Physical Society, Pacific Grove, CA (United States), 20-23 Oct 1993; Other Information: PBD: Oct 1993
- Country of Publication:
- United States
- Language:
- English
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