New features of superdeformed bands in {sup 194}Hg

Technical Report · Tue Aug 01 04:00:00 EDT 1995

DOI:https://doi.org/10.2172/168423· OSTI ID:168423

Janssens, R. V.F.; Ahmad, I.; Carpenter, M. P. ^[1]

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1. and others

A striking difference between superdeformed (SD) nuclei near A = 190 and those in the other regions is the behavior of the dynamic moment of inertia (lm) with the rotational frequency h{omega}. While the (lm) patterns of the SD bands near A = 130 and A = 150 show pronounced variations, the majority of the SD bands near A = 190 display the same large, smooth increase of (lm) within the frequency range 0.15 < {h_bar}{omega} < 0.40 MeV. Current interpretations of this rise of (lm) within mean field theories invoke the gradual alignment of quasiparticles occupying high-N intruder orbitals in the presence of pair correlations. It is a direct consequence of these interpretations that, after the quasiparticle alignments take place, (lm) will exhibit a downturn with increasing {h_bar}{omega} toward the rigid-body value. Up to now, no downturn in (lm) for the SD bands in the A = 190 mass region was observed, raising some doubt as to our understanding of pair correlations and alignment effects at these large deformations. An experiment was carried out at the 88-Inch Cyclotron facility of the Lawrence Berkeley Laboratory where excited states in {sup 194}Hg were populated with the reaction {sup 150}Nd({sup 48}Ca,4n) {sup 194}Hg at a beam energy of 206 MeV. The gamma rays emitted in the reaction were detected with the Gammasphere detector array (32 detectors for this experiment).

• Research Organization: Argonne National Lab., IL (United States)
• OSTI ID: 168423
• Report Number(s): ANL--95/14; ON: DE96000985
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
DEFORMED NUCLEI
GAMMA DECAY
GAMMA SPECTRA
HEAVY ION REACTIONS
MERCURY 194
NUCLEAR DEFORMATION
NUCLEAR STRUCTURE
PROGRESS REPORT