Isomer spectroscopy of neutron-rich 168Tb103. (November 2017)

• Record Type: Journal Article
• Authors: Gurgi, L.A.; Regan, P.H.; Söderström, P.-A.; Watanabe, H.; Walker, P.M.; Podolyák, Zs.; Nishimura, S.; Berry, T.A.; Doornenbal, P.; Lorusso, G.; Isobe, T.; Baba, H.; Xu, Z.Y.; Sakurai, H.; Sumikama, T.; Catford, W.N.; Bruce, A.M.; Browne, F.; Lane, G.J.; Kondev, F.G.; Odahara, A.; Wu, J.; Liu, H.L.; Xu, F.R.; Korkulu, Z.; Lee, P.; Liu, J.J.; Phong, V.H.; Yag, A.; Zhang, G.X.; Alharbi, T.; Carroll, R.J.; Chae, K.Y.; Dombradi, Zs.; Estrade, A.; Fukuda, N.; Griffin, C.; Ideguchi, E.; Inabe, N.; Kanaoka, H.; Kojouharov, I.; Kubo, T.; Kubono, S.; Kurz, N.; Kuti, I.; Lalkovski, S.; Lee, E.J.; Lee, C.S.; Lotay, G.; Moon, C.-B.; Nishizuka, I.; Nita, C.R.; Patel, Z.; Roberts, O.J.; Schaffner, H.; Shand, C.M.; Suzuki, H.; Takeda, H.; Terashima, S.; Vajta, Zs.; Yoshida, S.; Valiente-Dòbon, J.J.;
• Is Part Of: Radiation physics and chemistry. Volume 140(2017)
• Page Start: 493
• Page End: 496
• Publication Date: 2017-11
• Subjects: Structure of neutron-rich Terbium radioisotopes -- Gamma-ray spectroscopy and nuclear isomerism -- Possible two-quasiparticle configurations -- Nuclear energy-level schemes; Radiation chemistry -- Periodicals; Radiometry -- Periodicals; Radiation -- Periodicals; Chimie sous rayonnement -- Périodiques; 539.2
• DOI: 10.1016/j.radphyschem.2016.12.011
• Languages: English
• ISSNs: 0969-806X

Abstract

Abstract: In-flight fission of a 345 MeV per nucleon 238 U primary beam on a 2 mm thick 9 Be target has been used to produce and study the decays of a range of neutron-rich nuclei centred around the doubly mid-shell nucleus 170 Dy at the RIBF Facility, RIKEN, Japan. The produced secondary fragments of interest were identified event-by-event using the BigRIPS separator. The fragments were implanted into the WAS3ABI position sensitive silicon active stopper which allowed pixelated correlations between implants and their subsequent β -decay. Discrete γ -ray transitions emitted following decays from either metastable states or excited states populated following beta decay were identified using the 84 coaxial high-purity germanium (HPGe) detectors of the EURICA spectrometer, which was complemented by 18 additional cerium-doped lanthanum bromide (LaBr3 ) fast-timing scintillation detectors from the FATIMA collaboration. This paper presents the internal decay of a metastable isomeric excited state in the odd-odd nucleus 168 Tb, which corresponds to a single proton-neutron hole configuration in the valence maximum nucleus 170 Dy. These data represent the first information on excited states in this nucleus, which is the most neutron-rich odd-odd isotope of terbium (Z=65) studied to date. Nilsson configurations associated with an axially symmetric, prolate-deformed nucleus are proposed for the 168 Tb ground state the observed isomeric state by comparison with Blocked BCS-Nilsson calculations. Abstract : Highlights: First spectroscopy of excited states in the neutron-rich radioisotope 168 Tb. Decay gamma-rays identified using the EURICA gamma-ray spectrometer at the RIBF facility, RIKEN, Japan. Blocked BCS pairing Nilsson calculations.