title: Island of rare Earth nuclei with tetrahedral and octahedral symmetries: possible experimental evidence.
abstract: Calculations using realistic mean-field methods suggest the existence of nuclear shapes with tetrahedral Td and/or octahedral Oh symmetries sometimes at only a few hundreds of keV above the ground states in some rare earth nuclei around 156Gd and 160Yb. The underlying single-particle spectra manifest exotic fourfold rather than Kramers's twofold degeneracies. The associated shell gaps are very strong, leading to a new form of shape coexistence in many rare earth nuclei. We present possible experimental evidence of the new symmetries based on the published experimental results--although an unambiguous confirmation will require dedicated experiments.
authors.affiliation: Institut Pluridisciplinaire Hubert Curien IN2P3-CNRS/Université Louis Pasteur, F-67037 Strasbourg Cedex 2, France.
authors.forename: J
authors.initials: J
authors.lastname: Dudek
authors.forename: D
authors.initials: D
authors.lastname: Curien
authors.forename: N
authors.initials: N
authors.lastname: Dubray
authors.forename: J
authors.initials: J
authors.lastname: Dobaczewski
authors.forename: V
authors.initials: V
authors.lastname: Pangon
authors.forename: P
authors.initials: P
authors.lastname: Olbratowski
authors.forename: N
authors.initials: N
authors.lastname: Schunck