Identification of the missing rotation-aligned
Abstract
The rotation-aligned structure has been verified for 196Hg by the identification of the state. Form half-life measurements we find B(E2) values for the 12+ → 10+ and 10+ → 8+ transitions close to those in 198Hg. Evidence is also presented for the existence of this state in 194Hg.
References (15)
- D. Proetel et al.
Nucl. Phys.
(1974) - R.M. Lieder
Nucl. Phys.
(1975) - R. Kroth
Phys. Lett.
(1980) - F. Rösel et al.
At. Data Nucl. Data Tables
(1978) - R. Bengtsson et al.
Nucl. Phys.
(1979) - D. Mertin
Nucl. Phys.
(1978) - Y. Gono
Nucl. Phys.
(1979)
Cited by (36)
Nuclear Data Sheets for A=194
2021, Nuclear Data SheetsExperimental nuclear structure and decay data are evaluated for all of 14 known nuclides of mass 194 (Ta, W, Re, Os, Ir, Pt, Au, Hg, Tl, Pb, Bi, Po, At, Rn). Detailed evaluated spectroscopic information is presented for each reaction and decay experiment, and by combining all the available data, recommended values are provided for energies, spins and parities and half-lives of levels, together with energies, branching ratios and multipolarities of gamma radiations from the levels, and characteristics of beta and alpha radiations in radioactive decays. No excited states have yet been identified in 194Ta, 194W, and 194Rn. Only limited spectroscopic data are available for 194Re, with a 45−μs isomer identified, but its absolute energy yet to be determined. Only two levels at unknown absolute energies are reported for 194At, both of which are isomeric but neither can be unambiguously identified as the ground state. Data are scarce for 194Os, 194Bi and 194Po, while 194Pt, 194Au, 194Hg, 194Tl and 194Pb are well studied through decays and reactions. For 194Ir, although a major (n, γ), E=thermal study and two particle-transfer studies provide large amounts of spectral data, still several problematic issues are found in the assignment of multipolarities for the secondary gamma transitions in the (n, γ) study by 2008Ba25, 1998Ba85 and 1998Ba42, all from the same group. Some issues have been resolved by the evaluators, but we suggest that further experimental work is needed on 194Ir structure to resolve standing issues, and verify the conclusions made by 2008Ba25. Our attempt to contact the prime authors of the 2008Ba25 paper was not successful. The present work supersedes all the earlier evaluations of A=194 nuclides by 2006Si17, 1996Br26, 1989Si01 and 1972Au11.
Nuclear Data Sheets for A = 196
2007, Nuclear Data SheetsThe 1998 version of nuclear data sheets for A = 196 has been revised and updated on the basis of the experimental results from various decay and reaction studies before January 2006. The experimental data for all known nuclei of A = 196 (Os,Ir,Pt,Au,Hg, Tl,Pb,Bi,Po,At,Rn) have been reevaluated. The experimental methods, references,Jπ arguments,and necessary comments are given in the text. Summary band structure drawings and level schemes from both radioactive decay and reaction studies are presented. Also of special interest are the new identification of superdeformed bands in 196Pb and 196Bi.
Nuclear Data Sheets for A = 194
2006, Nuclear Data SheetsNuclear spectroscopic information for known nuclides of mass number 194 (Re,Os,Ir,Pt,Au,Hg,Tl,Pb,Bi, Po,At) with Z = 75 to 85 and N = 119 to 109 have been evaluated and presented together with adopted energies and Jπ of levels in these nuclei. No excited state data are yet available for 194Re and 194At. Many superdeformed structures are known in A = 194: three SD bands in 194Hg, two of which are connected to the normal-deformed structures; six SD bands in 194Tl; and three SD bands in 194Pb, one of which is connected to the normal-deformed structure. In addition four magnetic-rotational (MR) dipole bands are known in 194Pb together with many other dipole bands which are probable multi-quasiparticle structures. This evaluation supersedes previous full evaluations of A = 194 published by 1996Br26, 1989Si01, 1977Ha46 and 1972Au11.
Nuclear g factors and structure of high-spin isomers in <sup>190,192,194</sup>Pt and <sup>196,198</sup>Hg
2006, Nuclear Physics AThe integral perturbed angular distribution (IPAD) method in an external magnetic field has been used to measure the g factors of isomers in the 190,192,194Pt and 196,198Hg nuclei, populated in the ()-reaction. The results are as follows: 190Pt, , , ; 192Pt, , , ; 194Pt, , ; 196Hg, , ; 198Hg, , . The intrinsic structure of the isomers is discussed. The 12+ states have the rotational-aligned structure. The missing rotation-aligned state is suggested to be isomeric in 194Pt (instead of the 10+ state) and to which the value has to be attributed. From the g factors of the 10− states in 190Pt and 192Pt, which have the configuration , the anomalous -factor for neutrons has been derived as . The trend from negative g factors of the 7− states in the 196,198Hg nuclei to positive values for the corresponding states in the 190,192,194Pt nuclei indicates a change in the intrinsic structure of the lowest negative-parity bands, from mainly in Hg to mainly in Pt.
Nuclear data sheets for a = 196
1998, Nuclear Data SheetsThe 1995 version of nuclear data sheets for A=196 has been revised. The experimental data for all known nuclei of A=196 (Os, Ir, Pt, Au, Hg, Tl, Pb, Bi, Po, At, Rn) have been reevaluated. Summary band structure drawings and level schemes from both radioactive decay and reaction studies are presented. Associated spectroscopic data and adopted properties for levels and γ rays are given in tables. Also of special interest are the new identification of a superdeformed band and of a two-particle-two-hole-intruder state in196Pb.
Nuclear data sheets for A = 194
1996, Nuclear Data SheetsAbstract:Experimental data pertaining to all nuclei with mass A = 194 were evaluated. Level schemes from both radioactive decay and reaction studies are presented, along with associated tables of experimental data and adopted properties for levels and γ rays. The literature cutoff date for this revision is September 30, 1996. This revision replaces 89SiO1. Extensive high-spin experiments using large gamma-detector arrays have revealed superdeformed structures in194Hg (three SD bands: Yrast and pair of excited signature partners),194Tl (six SD bands: Three pairs of signature partners), and194Pb (three SD bands: Yrast and pair of excited signature partners). For yrast bands (SD-1) in194Hg and194Pb, connecting transitions between the SD band and normal bands have recently (96Kh04, 96Lo12,96Br07) been reported. Several dipole (oblate) bands in194Pb, some based on high-K (oblate) states have been reported from similar in-beam γ-ray experiments. New γγ coincidence measurements (93Ko59, 94KoZQ) using the193Ir(n,γ) reaction helped to place several transitions in the level scheme and established the 31.85-ms194Ir isomer at 147.078 KeV 5. Results from the first study of the193Ir(d,p) reaction (94Ga30) agree with those from (n,γ). Unpublished (95TeZZ) γγ coincidence results (using HERA, an array of 20 intrinsic germanium detectors) revealed a new level in194Pt at 1737.4 KeV. It also provided correct placement in the decay scheme for many γ rays from194Au ϵ decay. Recent measurements (92Hu04) of the α-decay chain202Fr–196At–194Bi confirm the existence of194Bi isomers, and show population to previously unknown levels at 218 and 396 KeV in194Bi.Cutoff Date:All data received by September 30, 1996 were evaluated.General Policies and Organization of Material:See the January issue of Nuclear Data Sheets.Acknowledgments:Evaluators wish to thank R.R.P. Teixeira (95TeZZ) for making available their unpublished data on194Au ϵ decay.General Comments:The analysis of γ-ray data is described in detail in 86BrZQ. The γ-ray energies given by various authors were fit to a level scheme for each data set through a weighted least-squares analysis. The scales for the corresponding intensities, which were assumed to be linearly related, were adjusted using the methods of Tepel (80TeZW) and Lederer (92LeZJ). Uncertainties of absolute γ-ray intensities were determined using the method of Browne (86Br21).