Excited State Data Research Articles

Nuclear Data Sheets for A=254

Spectroscopic data for known A=254 nuclides (U, Cf, Es, Fm, Md, No, Lr and Rf) have been updated and re-evaluated, superseding the data presented in the previous evaluation 2005Bh12 published by A. Bhagwat, N.J. Thompson and J.K. Tuli. With the exception of the 254No nuclide, excited-state data for A=254 nuclei are largely unknown. The decay of the 184−μs isomer in 254No has been studied in two independent experiments, results of which differ significantly, thus precluding adoption of any one particular decay scheme. Only the features that are consistent in these studies are included in the Adopted dataset, whereas independent decay schemes are presented in separate datasets. Information is also presented here for possible production of the 254U nuclide in a study (1960Di03) of debris of the first large-scale thermonuclear test (Ivy Mike) of November 1, 1952 in the Pacific Ocean.

Nuclear Data Sheets for A = 61

The evaluated spectroscopic data are presented for known nuclides of mass 61 (Sc,Ti,V,Cr,Mn,Fe,Co,Ni, Cu,Zn,Ga,Ge). Excited-state data are nonexistent for 61Sc, 61Ti, 61V, and 61Ge. Significant amounts of new data have been added since the previous NDS evaluation of A=61 nuclides (1999Bh04). 61Sc nuclide is now experimentally known, but without any knowledge of its half-life. The ground state half-lives of 61Ti and 61V are now determined. Excited-state data have become available for 61Cr, 61Mn and 61Ga, while for 61Ge, five excited states were erroneously assigned in the previous evaluation, these have been omitted here. Improved and extensive high-spin excitations are available for 61Fe, 61Cu and 61Zn, including several new superdeformed structures in 61Cu and 61Zn. Thermal neutron capture γ-ray data are available in detail from 2004Ra23. The radioactive decay schemes of 61Sc and 61Ti are not known, while those for 61V, 61Fe and 61Ge are poorly known. This work benefited from the earlier full evaluations of A=61 published by 1999Bh04, 1983Ek01 and 1975Au05 and the one published in an ‘update’ mode by 1992Zh31. The data and conclusions presented in the current work supersede those in all the previous evaluations.

Nuclear Data Sheets for A = 71

The evaluated spectroscopic data are presented for experimentally known nuclides of mass 71 (Mn,Fe,Co,Ni,Cu,Zn,Ga,Ge,As,Se,Br,Kr). Excited-state data are nonexistent for 71Mn, 71Fe, 71Co and 71Kr. Significant new data have been added since the last evaluation of A=71 nuclides by M. Bhat (1993Bh02). Excited states are now known in 71Ni and 71Cu, and enhanced information about high-spin excitations is available for 71Ga, 71As and 71Br. The decay schemes of radioactive isotopes 71Mn and 71Fe are not known at all, and those for 71Co, 71mNi and 71Kr are not known well. For the decay of 71Cu, 71gNi, and 71Br, extensive data are available, but in the opinion of the evaluators the decay schemes still seem incomplete. This work supersedes earlier full evaluations of A=71 published by 1988Bh01, 1979Ke06 and 1973Al33, and the last one published in ‘update’ mode by 1993Bh02.

Nuclear Data Sheets for A = 58

The evaluated spectroscopic data are presented for known nuclides of mass 58 (Ca,Sc,Ti,V,Cr,Mn,Fe,Co,Ni,Cu,Zn). Excited-state data are nonexistent for 58Ca, 58Sc, and 58Zn; and very scarce for 58Ti and 58V, with only one tentative level in each case. Except for half-lives, no other radioactive decay data are available for the decay of 58Sc and 58Ti. The radioactive decays of 58V, 58Cr and 58Zn are not considered as well established. Superdeformed structures are known in 58Ni (two bands) and in 58Cu (one band). Prompt proton decay of high-spin states in 58Ni for eight levels and prompt α decay for two states have been identified. In 58Cu, one high-spin state decays by prompt proton emission. Very complex high-spin structures are now known for 58Ni from the work by 2009Jo03.

Nuclear Data Sheets for A = 84

The evaluated spectroscopic data are presented for 12 known nuclides of mass 84 (Ga, Ge, As, Se, Br, Kr, Rb, Sr, Y, Zr, Nb, Mo). Except for the stable nuclides 84Sr and 84Kr, extensive new data are available for all the other nuclides since the 1997 evaluation by J.K. Tuli (1997Tu02) of A = 84 nuclides. Many precise Penning-trap mass measurements since AME-2003 for A = 84 nuclides (2009Re03,2008Ha23,2008We10,2007Ke09,2006Ka48,2006De36,2006Ri15) have resulted in improved Q values and separation energies. However, many deficiencies still remain. Some examples are given below. Excited-state data for 84Ga and 84As are nonexistent, and those for 84Ge are scarce. The radioactive decay schemes of 84Ga, 84Ge, 84Se, 84Y (39.5 min), 84Y (4.6 s), 84Zr and 84Nb suffer from incompleteness and that for 84Mo decay is not known at all. The energy ordering of the two activities (39.5 min and and 4.6 s) of 84Y is not well established, although, high-spin with tentative spin-parity of (6+) is adopted here as the ground state of 84Y based on weak arguments. From a conference report published in 2000, it is clear that extensive experiments were done to investigate decays of 84Zr and 84Y, but details of these studies never appeared in literature and none were made available to the evaluators when requested from original authors. This evaluation was carried out as part of ENSDF workshop for Nuclear Structure and Decay Data Evaluators, organized and hosted by the “Horia Hulubei” National Institute for Physics and Nuclear Engineering, Bucharest, Romania during March 30, 2009 – April 3, 2009. Names of the evaluators principally responsible for evaluation of individual nuclides are given under the respective Adopted data sets.

Nuclear Data Sheets for A = 78

The evaluated spectroscopic data are presented for known nuclides of mass 78 (Ni,Cu,Zn,Ga,Ge,As,Se,Br,Kr,Rb,Sr,Y,Zr). Excited-state data are nonexistent for 78Ni, 78Cu and 78Zr. For 78Zr, only the isotopic identification is established without any knowledge of its half-life and decay modes. Only limited excited state data exist for 78Y. The radioactive decays of the following isotopes are not considered by the evaluators as well established: 78Cu, 78mRb, 78Sr and 78Y. High-spin excitations are known for 78As, 78Se, 78Br, 78Kr, 78Rb and 78Sr. Significant amounts of new data have been added since the last NDS publication of A = 78 evaluation more than 18 years ago. This work supersedes earlier full evaluations of A = 78 published by 1981Si13 and 1975Ru01 and the one published in ‘update’ mode by 1991Ra06.

Nuclear Data Sheets for A = 64

The evaluated spectroscopic data are presented for known nuclides of mass 64 (V,Cr,Mn,Fe,Co,Ni,Cu,Zn,Ga,Ge,As,Se). Excited-state data are nonexistent for 64V, 64Cr, 64As and 64Se. Except for half-lives, no other radioactive decay data are available for the decay of 64V, 64As and 64Se; and those for the decays of 64Cr, 64Mn, 64Fe, 64Co and 64Ge are not considered as definitive. There are several high-spin studies for 64Zn nuclide, but many inconsistencies are noted in this evaluation and complete details of data in these studies are generally lacking in the published literature. This work supersedes earlier full evaluations of A = 64 by 1996Si12, 1979Ha35, 1974Au04 and 1967Ve09; and a mid-strem evaluation by 1991Si03 published in an 'update' mode.

Nuclear Data Sheets for A = 131

Nuclear spectroscopic information for known nuclides of mass number 131 (Cd,In,Sn,Sb,Te,I,Xe,Cs,Ba,La,Ce,Pr,Nd,Pm,Sm,Eu) with Z = 49 to 63 and N = 82 to 68 have been evaluated and presented together with adopted energies and Jπ of levels in these nuclei. No excited-state data are yet available for 131Cd, 131Sm and 131Eu. Fairly rich structures are known in all other A = 131 nuclides. Superdeformed and highly-deformed structures are known in 131Ce (two SD bands) and in 131Pr (two HD bands). This evaluation represents a complete update of previous evaluations of A = 131 by Yu.V. Sergeenkov, Yu.L. Khazov, T.W. Burrows, M.R. Bhat (1994Se10).

Electron-impact ionization of laser-excited sodium atom.

We report the experimental results of the total electron-impact ionization cross sections of laser-excited $3P$ sodium in the energy range from threshold to 30 eV. These cross sections were measured simultaneously for both ground-state and $3P$ excited-state atoms as a function of electron-impact energy. Excited-state data were calibrated with respect to the ground-state data that were normalized to the recent Johnston and Burrow measurements [Phys. Rev. A 51, R1735 (1995)]. We find good general agreement with theory. However, the position of the maximum is almost the same as that predicted by the calculations employing generalized oscillator strengths based on the Born approximation, and is at a higher energy than that which the convergent close-coupling predicts.

Nuclear Data Sheets for A = 64

Abstract:The evaluated spectroscopic data are presented for known nuclides of mass 64 (Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge). Excited-state data are nonexistent for 64Mn and 64Fe. Radioactive decay data for 64Mn are not available and those for 64Fe, 64Co and 64Ge are not considered definitive. The following nuclides have not yet been identified but, amongst other nuclides, have been included in theoretical calculations: 64Ca (92Ma60,91To03,91Hi10); 64Cr (95Re20,95Ri05,95Au04); 64As (95Au04); 64Se (93Sh11). The literature available up to June 25, 1996 has been consulted. This work supersedes earlier evaluations of A=64 published in Nuclear Data Sheets (91Si03,79Ha35,74Au04,67Ve09). Cutoff Date:Literature available up to June 25, 1996 has been consulted. General Policies and Organization of Material:See the January issue of Nuclear Data Sheets. Acknowledgments:The evaluator thanks Alfredo Galindo-Uribarri at Chalk River for discussions and communicating results of his recent in-beam experiment on 64Zn, prior to publication. General Comments:The statistical analysis of γ-ray data and deduced level schemes is carried out through computer codes available at Isotopes Project, Berkeley and Nuclear Data Center, Brookhaven. The methodology and procedures for some of these codes are described by 86BrZQ and 86Br21. A general 3% uncertainty is assumed in quoted theoretical internal conversion coefficients taken mainly from 68Ha53. The values of μ and Q are from compilation by 89Ra17, when available.

12C( gamma,p)11B cross section from 80 to 157 MeV.

The $^{12}\mathrm{C}$(\ensuremath{\gamma},p${)}^{11}$B differential cross section has been measured over proton angles ranging from 58\ifmmode^\circ\else\textdegree\fi{} to 128\ifmmode^\circ\else\textdegree\fi{}, using tagged photons of energy 80--157 MeV, for low-lying regions of residual excitation energy in $^{11}\mathrm{B}$. The data have been compared with four different types of calculation. It is shown that scaling of the cross section with momentum mismatch occurs for both the ground-state and excited-state data.

Spectroscopic studies of the coupled binuclear non-heme iron active site in the fully reduced hydroxylase component of methane monooxygenase: comparison to deoxy and deoxy-azide hemerythrin

A combination of circular dichroism (CD) and magnetic circular dichroism (MCD) spectroscopies has been used to probe the geometric and electronic structure of the binuclear Fe(II) active site of the reduced hydroxylase component of methane monooxygenase (MMOH). Excited-state data provide the numbers and energies of d→d transitions which are interpreted in terms of ligand field calculations to estimate the geometry of each iron. Variable-temperature variable-field (VTVH) MCD data are analyzed by using a non-Kramers doublet model to obtain the zero field splitting (ZFS) and g∥ value of the ground state and the excited sublevel energies. These results are further interpreted in terms of a spin Hamiltonian which includes the ZFS of each Fe 2+ combined with the exchange coupling between iron centers

Nuclear data sheets update for A = 64

The evaluated spectroscopic data are presented for eight known nuclides of mass 64 (Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge). Excited-state data are nonexistent for 64Mn and 64Fe. Very little information is available for 64Ge and γ-ray data are scarce for 64Co and 64Ni. Some high-spin data are available for 64Ga and 64Ge, in spite of several in-beam γ-ray experiments on 64Zn and 64Cu. Further work on 64Zn and 64Ga seems to be in progress at Daresbury (90LiZS) through heavy-ion reactions. Radioactive decay data for 64Mn are not available and those for 64Fe, 64Co and 64Ge are not considered definitive.

Nuclear data sheets for A = 74

The 1976 version of Nuclear Data Sheets for A = 74 (76Ko07) has been revised. Nuclear structure data for known nuclides (Zn, Ga, Ge, As, Se, Br, Kr, Rb) of A = 74 have been evaluated and presented. The excited-state data on 74Rb are non-existent and those for 74Zn, 74Ga, and 74Kr are scarce. High spin levels are known for 74Se, 74Br and 74Kr.

Proflavin binding to poly[d(A-T)] and poly[d(A-br5U)]: triplet state and temperature-jump kinetics.

The delayed fluorescence properties of proflavin have been exploited in studies of the excited-state binding kinetics of the dye to poly[d(A-T)] and its brominated analogue poly[d(A-br5U)] at room temperature and pH 7. The two analyzed luminescence decay times of the DNA-dye complex are dependent on the total nucleic acid concentration. This dependence is shown to reflect a temporal coupling of the intrinsic delayed emission decay rates with the dynamic chemical kinetic binding processes in the excited state. Temperature-jump kinetic studies conducted on the brominated polymer and corresponding information on poly[d(A-T)] from a previous study [Ramstein, J., Ehrenberg, M., & Rigler, R. (1980) Biochemistry 19, 3938-3948] provide complementary information about the ground state. In the ground state, the poly[d(A-T)]-proflavin complex has one chemical relaxation time, which reaches a plateau at high DNA concentrations. The brominated DNA-dye complex exhibits two relaxation times: a faster relaxation mode that behaves similarly to that for the unhalogenated DNA and a slower relaxation mode that is apparent at high DNA concentrations. The ground-state kinetic data are analyzed in terms of two alternative models incorporating series and parallel reaction schemes. The former consists of two sequential binding steps--a fast bimolecular process followed by a monomolecular step--while the latter consists of two coupled bimolecular steps. A similar analysis for the excited-state data yields reasonable kinetic constants only for the series model, which, in accordance with previous proposals for acridine intercalators, consists of a fast outside binding step followed by intercalation of the dye. A comparison of the ground- and excited-state kinetic parameters reveals that the external binding process is much stronger and the intercalation is much weaker in the excited state. That the excited-state data are only consistent with the series model suggests that delayed luminescence studies may provide a general tool for distinguishing between the two kinetic mechanisms. In particular, we demonstrate the use of delayed luminescence spectroscopy as a tool for probing dynamic DNA-ligand interactions in solution.

Magnetoelastic Coupling Constants of Rare Earth Ions from Optical-Spectroscopic Data

Measurements are presented of the shifts with uniaxial pressure of the exchange split F7/22(Γ7) levels of Ce3+ in YIG. By assuming that the pressure shifts of the exchange splittings scale as the unshifted splittings, the Ce3+ excited-state data is used to predict the shifts in the F7/22(Γ7) ground state of Yb3+ in YIG. The Yb3+ shifts are used to predict low-temperature magnetoelastic coupling constants of Yb3+ in YIG. The predicted constants are in good agreement with those previously measured using a strain gauge.