| 1. |
- Cederwall, Bo, et al.
(författare)
-
HIGH-SPIN STATES OF BA-120
- 1991
-
Ingår i: Zeitschrift für Physik A Hadrons and Nuclei. - 0939-7922 .- 1431-5831. ; 338:4, s. 461-462
-
Tidskriftsartikel (refereegranskat)abstract
- The very neutron deficient nucleus 120Ba has been investigated in a high-spin gamma-spectroscopic study. The yrast band of 120Ba is extended up to spin 22 h and one tentatively assigned negative-parity side band is observed up to spin 15 h. The experimental results are compared with Total Routhian Surface calculations.
|
|
| 2. |
- Cederwall, Bo, et al.
(författare)
-
SIGNATURE INVERSION IN CS-120 - EVIDENCE FOR A RESIDUAL PN INTERACTION
- 1992
-
Ingår i: Nuclear Physics A. - 0375-9474 .- 1873-1554. ; 542:3, s. 454-478
-
Tidskriftsartikel (refereegranskat)abstract
- High-spin states have been observed in the odd-odd isotope 120Cs in S-32-induced reactions. The previously known band is extended to higher spin and several new bands are identified. Band-head configurations have been inferred by comparing the band properties with known bands in the odd nuclei 121Cs and 121Ba. A remarkable signature inversion is observed in the pi-h11/2 x nu-h11/2 band. The experimental data are compared with calculations made within the total routhian surface model and the two-particle plus triaxial rotor model. It is concluded that a significant residual pn interaction rather than triaxiality is responsible for the signature inversion phenomenon in the pi-h11/2 x nu-h11/2 band of 120Cs.(~)[GRAPHICS]
|
|
| 3. |
- DORING, J, et al.
(författare)
-
EVIDENCE FOR NEW ISOMERS AND BAND STRUCTURES IN RB-80
- 1992
-
Ingår i: Physical Review C. Nuclear Physics. - 0556-2813 .- 1089-490X. ; 46:6, s. R2127-R2131
-
Tidskriftsartikel (refereegranskat)abstract
- Excited states in the doubly odd nucleus Rb-80 have mainly been studied via the Zn-68(F-19,alpha3n) reaction at 72 MeV beam energy utilizing the NORDBALL detector system. The level scheme has been extended up to a (15+) state at 4446 keV excitation energy. In the low-spin region seven new isomers with lifetimes in the nanosecond region have been found. In addition, a 6+ isomer with a half-life of the order of mus has been identified at an excitation energy of 494.4 keV. For the level sequence built on this isomer positive parity is suggested and the states are ascribed to the intruder two-quasiparticle configuration (pig9/2 x nug9/2) and collective excitations.
|
|
| 4. |
- DORING, J, et al.
(författare)
-
HIGH-LYING 3-QUASI-PARTICLE BANDS AND SIGNATURE SPLITTING IN RB-81
- 1994
-
Ingår i: Physical Review C. Nuclear Physics. - 0556-2813 .- 1089-490X. ; 50:4, s. 1845-1850
-
Tidskriftsartikel (refereegranskat)abstract
- Two new high-lying level sequences of negative parity have been identified in the odd-proton nucleus Rb-81 by in-beam gamma-ray spectroscopy using the reactions Br-79(alpha, 2n) at 27 MeV and Zn-68(F-19, alpha2n) at 72 MeV. One sequence, dominated by M1 transitions, is interpreted as a three-quasiparticle band predominantly containing a neutron in the p1/2, p3/2, or f5/2 subshell coupled to g9/2 proton and g9/2 neutron excitations. The other new level sequence forms the three-quasiparticle extension of the unfavored negative-parity band, but the states decay also by E1 transitions. The signature splitting points to a configuration where an aligned g9/2 proton pair is involved.
|
|
| 5. |
- JERRESTAM, D, et al.
(författare)
-
COLLECTIVE EXCITATIONS IN CD-106
- 1994
-
Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474 .- 1873-1554. ; 571:2, s. 393-412
-
Tidskriftsartikel (refereegranskat)abstract
- High Spin states in 106Cd were populated by the reactions Zr-94(O-17, 5n) and Ge(S-32, 4n) at 80 MeV and at 148 MeV, respectively. The gamma-decay was studied by gamma-spectroscopic methods using the Nordball multi-detector army. Protons and alpha-particles were detected in particle detector system, thus selecting the neutron channel. The experiment included gamma-ray yields, gammagamma-coincidences and gamma-ray angular relation measurements. Collective bands extending up to spin 26+, 20- and 21-, have been observed in 106Cd. A new lifetime Of 11(-3)+6 ns for the 16+ state at 7118.7 keV has been found. Both total Routhian surfaces and spin diabatic surfaces have been calculated and used for assigning quasiparticle configurations to the bands. The (+, 0) band is assigned as a nuh11/2(2) configuration below I = 16+ and at higher spins suggested to be built on a pig9/2(2)nuh11/2(2) configuration. The large hindrance observed for the decay from the 16+ state supports the latter assignment. With the alignment of the nuh11/12(2) pair the deformation is predicted to change from (epsilon2,gamma) = (0.13,-2-degrees) to (0.17, 4-degrees). The configuration of the negative parity bands is assigned as either a nuh11/2(1)d5/2(1) or a nuh11/2(1)(g7/2xd5/2)1, With (epsilon2, gamma) = (0.14,9-degrees.
|
|
| 6. |
- JUUTINEN, S, et al.
(författare)
-
EVIDENCE FOR BAND TERMINATION IN XE-118
- 1991
-
Ingår i: Zeitschrift für Physik A Hadrons and Nuclei. - 0939-7922 .- 1431-5831. ; 338:3, s. 365-366
-
Tidskriftsartikel (refereegranskat)abstract
- The yrast band of Xe118 has been extended up to tentatively I-pi = 34+ in a heavy-ion in-beam gamma-spectroscopic study using the NORDBALL detector array. A band crossing is observed at the highest spins and interpreted within the Modified Oscillator Model as a transition to a terminating band.
|
|
| 7. |
- LIDEN, F, et al.
(författare)
-
ALIGNMENT PROCESSES IN CS-119, CS-121 AND CS-123
- 1992
-
Ingår i: Nuclear Physics A. - 0375-9474 .- 1873-1554. ; 550:2, s. 365-390
-
Tidskriftsartikel (refereegranskat)abstract
- Rotational band structures have been observed in the odd-A Cs isotopes 119Cs, 121Cs and 123Cs. The previously known bands have been extended to higher spin values and several new bands have been established. Alignments of both h11/2 protons and neutrons are seen. Of special interest are the alignment frequencies in the (tentative) [422]3/2+ and [404]9/2+ bands which indicate a configuration-dependent proton pairing. Furthermore, the variation of the interaction strength at the first band crossing in the h11/2 bands does not follow the standard cranked-shell-model predictions. This feature is in line with previous systematic observations of alignment processes in high-j intruder bands, and might infer an additional band mixing due to a neutron-proton interaction.(~)[GRAPHICS]
|
|
