Octupole and quadrupole structures in the N=88 nucleus 152Gd (original) (raw)

New high-spin states of 147Nd and 145Ce: Octupole correlation in the N = 87 isotones

The European Physical Journal A, 2005

High-spin states of the N = 87 nuclei, 147 Nd and 145 Ce, have been populated in the 12 C + 238 U and 18 O + 208 Pb fusion-fission reactions at 90 MeV and 85 MeV bombarding energy, respectively. The emitted γ-radiation was detected using the Euroball III and IV arrays. High-spin states of the 147 Nd isotope have been identified for the first time. The high-spin yrast and near-to-yrast structures of the 145 Ce nucleus have been considerably extended. The newly observed structures, discussed by analogy with the neighbouring isotones, show the coupling of an h 9/2 neutron to the quadrupole and octupole excitations of the core. PACS. 21.10.-k Properties of nuclei; nuclear energy levels-21.10.Re Collective levels-23.20.Lv γ transitions and level energies-27.60.+j 90 ≤ A ≤ 149

Complete spectroscopy of the 162Dy nucleus

Nuclear Physics A, 2006

States in 162 Dy have been populated by (n, γ), (n, e −), and (α, 2n) reactions in order to characterize a complete set of low K bands below 2 MeV. The (n, γ) and (n, e −) measurements were made using high precision curved crystal and β − spectrometers. Gamma-gamma coincidence and DCO measurements were made following the (α, 2n) reaction using an array of Compton-suppressed Ge detectors. Using all these data and employing the Ritz combination principle, a level scheme was developed which represents one of the most complete and extensive spectra of levels available for comparison with nuclear models. The observed positive and negative parity bands are discussed in terms of collective quadrupole and octupole vibrational excitations as well as 2 quasi-particle excitations.

In-beam γ-ray spectroscopy of 102Cd

Nuclear Physics A, 1997

Neutron deficient nuclei close to ~°°Sn have been studied using the NORDBALL Ge-detector array together with ancillary particle detectors. Evaporation residues from the compound nucleus taSTe were identified with charged particle and neutron detectors. In this paper a considerable extension of the level scheme of the nucleus t°2Cd is presented. The strongest cascade of the new level scheme reveals an irregular sequence of dipole transitions above I ~r = l0 + extending up to spin 17. A strongly populated rather regular side band consisting of four quadrupole transitions ranging from spin 9 to spin 17 was also discovered. This band was tentatively assigned negative parity. Shell model calculations were performed and a very good agreement with the experimental results was found. The excited states could successfully be interpreted as neutron particle and proton hole excitations with respect to the doubly closed core 1~Sn50. (~) 1997 Elsevier Science B.V.

Rotation induced octupole correlations in the neutron-deficient 109Te nucleus

Physics Letters B, 1998

High spin states in the neutron deficient nucleus 109 Te have been populated with the 58 Ni q 54 Fe reaction at 220 MeV and investigated through g-spectroscopy methods at the GASP spectrometer making use of reaction channel selection with the ISIS Si-ball. The level scheme has been extended up to an excitation energy of f 12.1 MeV. The spins and parities of the observed levels are assigned tentatively supporting the identification of two bands of opposite parity connected by strong dipole transitions inferred to be of E1 character. Octupole correlations in 109 Te induced by rotation are suggested as the cause of this effect.

Discrete and continuum Gamma-ray studies of 147Gd and 148Gd

Nuclear Physics A, 1990

Discrete and continuum y-ray studies of the N = 83,84 nuclei 14'Gd and '%d have been performed using (36S, 5n) and (?S, 4n) reactions on '%d. The level schemes of both nuclei have been extended to excitation energies above 18.5 MeV, with assigned spins up to yh in 14'Gd and up to46fi in IdilGd. Evidence for a change in character along the yrast line from single particle to collective was found at the highest spins in 148Gd, but not in i4'Gd. For '48Gd a study of y-y correlation matrices revealed a ridge-valley structure with a ridge spacing indicative of supetdeformation. No evidence for a similar structure in 14'Gd was found.

In-beam spectroscopic studies of the nucleus 105Cd

Nuclear Physics A, 1995

High spin states in 1°5Cd have been studied using reactions l°6Cd(p, pn), l°6Cd(3He, 2p2n), 92Zr(160, 3n) and 76Ge(34S, 5n). The excited levels are dominated by a negative parity band structure up to spin 47/2-and a positive parity structure up to spin 27/2 +. The negative parity structure is based on z, hn/z excitations and undergoes a band crossing at hco ~ 0.44 MeV. This band crossing is interpreted as an alignment of a g7/2 neutron pair. The positive parity excitations are understood as due to z, g7/2 and z, ds/2 configurations. The results are discussed in terms of spin diabatic surface calculations.

Nuclear structure studies of 159Er up to high spin

2012

In the current work a detailed spectroscopic investigations of the gamma-decays from the excited states of the rare-earth nucleus 159Er has been performed to study the structural properties up to possible ultrahigh spins. The nucleus of 159Er had been populated by the reaction 116Cd(48Ca,5n ) at beam energy of 215-MeV in an experiment at Argonne National Laboratory using the Gammashphere array. Following a hypercube analysis of the collected data, new rotational bands were observed and the previously reported bands were extended up to possible spin through observation of new gamma-ray transitions in coincidence with the existing sequences. Possible angular intensity-ratio, B(M1)/B(E2)-ratios, measurements have been performed to confirm the nature of previously observed transitions and to assign multipolarites of the new ones. The band structures are discussed within the framework of cranked shell model calculations, revealing a diverse range of quasiparticle configurations. At spins...

Rotational bands in the doubly odd 130Cs nucleus

The European Physical Journal A, 2001

The band structures built on the 5 − isomeric state (T 1/2 = 3.46 m) in the doubly odd 130 Cs nucleus have been established up to I = 24h via the 124 Sn( 11 B, 5n) 130 Cs reaction. The previously observed bands based on the πh 11/2 ⊗ νh 11/2 , πg 7/2 ⊗ νh 11/2 and πd 5/2 ⊗ νh 11/2 configurations and a positive-parity side band with multiple connections to the α = 0 signature partner of the yrast πh 11/2 ⊗ νh 11/2 band have been extended to higher spins. A new band based on the πh 11/2 ⊗ νg 7/2 configuration is observed. The yrast πh 11/2 ⊗ νh 11/2 band exhibits anomalous signature splitting whose magnitude decreases up to spin 15 and then increases without restoring the normal signature splitting.