First evidence for triaxial superdeformation in 168Hf

Three superdeformed (SD) bands have been found in 168Hf. Lifetime measurements revealed a large quadrupole moment, Qt ∼ 11.4 eb, for the strongest band (TSD1). Theoretical calculations using the Ultimate Cranker code predict high-spin SD minima (ε2 ∼ 0.43) with stable triaxial deformations of γ ∼ +20° and γ ∼ -15°. The measured Qt value suggests that band TSD1 corresponds, most likely, to a deformation with a positive γvalue. This constitutes the first evidence for triaxial superdeformation in an even proton system

Identification of 181Hg and shape coexistence in odd-A Hg isotopes

In-beam γ-ray transitions in 181Hg, the lightest odd-A Hg isotope known thus far, have been identified from fragment mass-γ and γ-γ coincidence measurements. Five prolate deformed rotational bands were placed in the level scheme. A decoupled band built on the strongly prolate deformed 1/2-[521] ground state was observed up to 29/2-. A 5/2-[512] configuration is suggested for a pair of strongly coupled bands displaying no signature splitting. The other two bands are also signature partner bands. They are populated with the largest intensity and exhibit splitting. They have been associated with the mixed neutron i13/2 orbitals and are proposed to decay to an i13/2 isomeric state associated with an oblate state