Nuclear data sheets for A = 83

The 1975 version of Nuclear Data Sheets for A=83 has been revised. Detailed level and decay schemes, arguments for Jπ assignments, and experimental data are presented.     

Nuclear data sheets for A = 159

Nuclear data based upon reaction and radioactivity studies of mass 159 nuclei are presented.For A = 159 all nuclei with 63 ?Z?72 with the exception of Yb and Lu have been reported; but not much is known for Eu, Er, Tm, and Hf isobars other than their ground-state properties. The only stable nucleus with A = 159 is ¹⁵⁹Tb, and it has been studied in considerable detail both by nuclear reactions and radioactive decay of its neighboring isobars. Because of ambiguity in beta branching in ¹⁵⁹Eu decay and since the beta branch to ¹⁵⁹Tb g.s. in ¹⁵⁹Gd decay is known only approximately, the normalizations in these radioactive decays are rather uncertain.For brevity some of the older data have been omitted or referenced as other measurements.It has been attempted to include all available data prior to February 1, 1973.     

Nuclear data sheets for A = 74

The 1966 version of Nuclear Data Sheets for A = 74 has been revised on the basis of experimental data received prior to December 1, 1975. Results from approximately 95 papers and communications have been included in the present evaluation.Data on seven A = 74 nuclei are presented. The main features of the decay schemes for ⁷⁴Zn and 8.1-m ⁷⁴Ga appear to be known. An upper limit of 50% has been established for the β-decay branching ratio for 9.5-s ⁷⁴Ga. Both β⁺- and β^?,-decays of ⁷⁴As are well established. Many excited levels are known in ⁷⁴Ge, ⁷⁴As, and ⁷⁴Se from a variety of decay and reaction experiments, but few spin assignments are firm. The level identification for a 26.8-ns isomer in ⁷⁴As is uncertain. An 8.0-s activity previously assigned to ⁷⁴As is now believed to occur ¹⁹⁷Au. The decay schemes for two ⁷⁴Br isomers are reasonably well established, but the energy difference between the two isomers is not well known. The decay scheme for ⁷⁴Kr is well established, but results on excited levels in ⁷⁴Kr are contradictory.     

Nuclear data sheets for A = 117

Nuclear structure data available through June 1978 are compiled and evaluated. Adopted level and decay properties are given. The bulk of the data is presented pictorially for easy comparison. Experimental details, references, and additional comments, where required, are given in the text. All drawings, tables, and comments are reproduced from the evaluated nuclear structure data file (ENSDF). Any additions or corrections desired by the users should be addressed to the evaluators for maintenance and updating of the data fille.     

Nuclear data sheets for A = 78

Nuclear spectroscopic information for known nuclides of mass number 78 (Zn, Ga, Ge, As, Se, Br, Kr, Rb, Sr) have been evaluated and presented together with adopted energies and Jπ of levels in these nuclei. No data are yet available for excited states in ⁷⁸Zn. Data for ⁷⁸Rb and ⁷⁸Sr are very scarce.     

Nuclear data sheets for A = 219

Available information on decay characteristics and level structure for all nuclei with A = 219 has been examined. A summary and evaluation of experimental data, including adopted values and comparison with theory are presented. The individual level schemes are discussed, and comments pertaining to adopted spin and parity assignments and to gamma-ray multipolarities are given. Any apparent discrepancies and inconsistencies are pointed out.Much of the level information in the A = 219 mass chain is obtained from the α-decay of the A = 223 parent nuclei. While a summary of these results is reflected in both the level schemes and in discussions under “Level Properties” and “Gamma-Ray Properties”, the actual data are presented under the respective A = 223 parent.Decay energies and separation energies have been taken systematically from the 1977 Mass Adjustment (76WaBo, 77Wa08). Detailed comparison has been made between the adopted α-energies and the input values to the Mass Adjustment.     

Nuclear data sheets for A = 77

The 1966 version of the Nuclear Data Sheets for A = 77 has been revised on the basis of all experimental data received before January 1, 1973. Experimental data, detailed level schemes, and arguments for J^π assignments are presented. Two new isotopes, ⁷⁷Ga and ⁷⁷Rb, are now known to exist while a third, ⁷⁷Zn, has been tentatively identified. A significant amount of new information is now available on the ⁷⁷Ge, ⁷⁷As, ⁷⁷Se, and ⁷⁷Br level schemes.     

Nuclear data sheets for A = 127

The experimental results from various decays and reactions for the A=127 mass chain have been compiled and evaluated. Adopted values for the level and decay properties are tabulated.     

Nuclear data sheets for A = 202

Experimental data pertaining to nuclei with A = 202 are compiled and evaluated.     

Nuclear data sheets for A = 84

The 1971 version of the Nuclear Data Sheets for A = 84 has been revised on the basis of all experimental data received before March 1, 1979. Detailed level and decay schemes, arguments for J^π assignments and experimental data are presented. Three new isotopes, ⁸⁴Ge, ⁸⁴Zr, and ⁸⁴Nb, have been identified. For the isotopes ⁸⁴Ge, ⁸⁴As, ⁸⁴Y, and ⁸⁴Nb, however, little information is available. In the ⁸⁴Rb data, several inconsistencies occur, so that the level scheme is far from being well estabished.     

Nuclear data sheets for A = 140

Nuclear structure data for mass 140 nuclei are compiled and adopted level and gamma-ray properties are presented. The adopted values are based on all data received before August 1973.     

Nuclear data sheets for A = 128

Nuclear structure data available through December 1972 are compiled, and adopted level properties and decay schemes are presented. The first section of the compilation consists of drawings summarizing essentially all available reaction and radioactivity data. The second section, “Summary Sheets,” contains adopted level properties and, where space permits, tabulated data upon which they are based. The third section, “Data Sheets,” is used only for those nuclei requiring extensive data tabulations.     

Nuclear data sheets for A = 190

Experimental nuclear structure and decay data for nuclides of mass A=190 have been evaluated. This work supersedes the previous evaluation by M. R. Schmorak, published in Nuclear Data Sheets 9, 401 (1973). Because of the new experimental results which are incorporated, the present evaluation involves a complete revision of the level structure of every mass-190 nuclide except ¹⁹⁰Ir. It covers significant new results not included in the recent evaluation by R. E. Doebler and E. Browne (Table of Isotopes, 7th Edition, ed. by C. M. Lederer and V. S. Shirley, p. 1213ff, John Wiley and Sons, Inc. (1978)) for the following nuclides and reactions or decay schemes: ¹⁹⁰Os from ¹⁸⁹Os(n,γ) and Coulomb excitation; ¹⁹⁰Pt from (HI,xnγ) reactions and ¹⁹²Pt(p,t); ¹⁹⁰Au from ¹⁹¹Ir(α,5nγ); ¹⁹⁰Hg from (HI,xnγ) reactions; ¹⁹⁰Tl from ¹⁹⁰Pb ε decays; ¹⁹⁰Pb from ¹⁵⁴Gd(⁴⁰Ar,4nγ). Of the nuclei readily studied by nuclear reactions, little is presently known of the odd-odd ¹⁹⁰Ir, and there are only sketchy, preliminary data on high-spin states of ¹⁹⁰Au, which is expected to have a low-lying 11- isomer whose decay has not been observed. A recent measurement of the g-factor for the 24.1-ns isomer in ¹⁹⁰Hg suggests strongly that this state decays by an unobserved transition, whose existence requires confirmation.     

Nuclear data sheets for A = 149

The present work constitutes an updating of the previous A = 149 compilation which appeared in Nuclear Data Sheets in December 1962. The experimental results of over 130 papers up to August 1974 have been included in this compilation.Data are presented for nine nuclei (Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy). The bulk of the experimental information comes from decay studies, although one- and two-nucleon transfer reaction data from experiments performed since the 1962 compilation have made a major contribution to the determination of spins and parities. The Nd levels are almost entirely determined by (d,t) and (³He,α) data, pointing up the need for further study of the β^?-decay leading to this nucleus. The A = 149 nuclei are in a transition region from spherical to deformed nuclei. The systematics of spins and parities in this region will be useful in testing models of intermediate coupling.Absolute β^?-, γ+(ce)-, and ε(+β⁺)-branching ratios are given on the decay scheme drawings. These quantities are based on a (γ+ce) intensity balance normalized to 100% decay to the ground state of the daughter nucleus. Details of methods used for specific nuclides are discussed for the individual cases.     

Nuclear data sheets for A = 88

The Midstream Evaluation, A = 88 [Nuclear Data Tables A8, 345–371 (1970)] has been revised on the basis of experimental data received before September 1, 1975. Data for the nine known members of the A = 88 isobar are presented.Very little is known about ⁸⁸Se and the available data are inconsistent. The γ-ray spectrum following the ⁸⁸Br decay has been measured. The resulting level scheme for ⁸⁸Kr is shown in Drawing 2. The dashed levels result from energy sums involving only two γ-rays and no coincidence data. These data and the ⁸⁶Kr(t,p) data indicate that the levels at 1644.1 keV (β^?) and 1654 keV (t,p) are not equivalent. More decay and reaction data are required before the ⁸⁸Kr level properties can be considered firm. The γ-rays following the ⁸⁸Kr β-decay are well established. The agreement of the resulting ⁸⁸Rb level scheme with that obtained from the ⁸⁷Rb(d,p) reactions is quite good. The ⁸⁸Rb β-decay has been well established through many extensive measurements using several different source preparations. The levels of ⁸⁸Sr have been investigated through many reactions (more than 20 given here) and the ⁸⁸Rb β- and ⁸⁸Y ε-decays. Adopted levels through 4.85 MeV are given on the Data Sheets. Above 4.85 MeV inconsistencies in the various energy calibrations obscure the assignment of corresponding levels. A detailed discussion of the various ⁸⁸Sr(n,γ) experiments can be found in 69Ly07. The ⁸⁸Y ε-decay is presented as an adopted scheme derived from data discussed in ten publications. The levels of ⁸⁸Y are well established through many reactions including several (charged particle, nγ) which provide some very accurate level energies. The simple ⁸⁸Zr ε-decay is shown on Drawing 1. The adopted level properties are from the ⁹⁰Zr(p,t)⁸⁸Zr reactions. These data correspond well through 3 MeV. The ⁸⁸Nb ground-state and isomeric ε-decays need further work. The 14.3-m decay data presented here are in poor agreement with a recent measurement by 74Ba55 which identifies an additional 26 γ-rays, 18 of which are not placed in the decay scheme. The tentative assignment of J^π(^88gNb)=(8⁺) and J^π(^88mNb)=(4^?) are based on weak arguments and should be reconsidered in the light of new decay data. The relative position of these levels is unknown. Very little data are available for ⁸⁸Mo.In a few cases unpublished data have been frequently cited by other researchers. These unpublished data have been included for reference and are clearly marked as such. The Adopted Properties were not influenced by these data.     

Nuclear data sheets for A = 237

The available structure information for all nuclei with mass number A = 237 is presented. Various decay and reaction data are evaluated and compared. Adopted data, levels, spin, parity, and configuration assignments are given.     

Nuclear data sheets for A = 148

Nuclear structure information available to December 1976 has been reviewed. The level properties obtained from various reaction and decay experiments are shown in the drawings. Experimental details, references, and comments are given in the text. Level bands are indicated and referenced to systematics.     

Nuclear data sheets for A = 198

Nuclear structure information available to April 1977 has been reviewed. The level properties obtained from various reaction and decay experiments are shown in the drawings. Experimental methods, references, and comments are given in the text. Proton-neutron configurations are associated with a number of levels in odd—odd nuclei.     

Nuclear data sheets for A = 194

Nuclear structure information available to July 1977 has been reviewed. The level properties obtained from various reaction and decay experients are shown in the drawings. Experimental methods, references, and comments are given in the text. Proto-neutron configurations are associated with a number of levels in odd-odd nuclei.     

Nuclear data sheets for A = 214

Nuclear structure information for all nuclei with mass number A = 214 is evaluated. The results from various decay experiments and reaction studies arc compared. Adopted data, levels, and spin and parity assignments are given.