Elliot Warburton

• University of Leicester

Excited states in the N = 28 isotones 54Fe and 55Co were populated in the bombardment of 54Fe with 3He ions. The subsequent de-excitation was studied using experimental in-beam techniques including γ-γ coincidences and γ-ray angular distributions. A number of previously unobserved levels were discovered in 54Fe and a new high-spin complex was assig...

Gamma-ray data from 74,76Ge+18O fusion-evaporation reactions are analysed to provide data on yrast decay schemes in 87,89Zr, 87,88,89,90Y and 86Sr. The data include excitation functions, angular distributions, gamma - gamma coincidences, linear polarisation measurements and lifetimes deduced from both Doppler shift attenuation and recoil distance m...

Bands of states in 81Y have been identified by using a particle-gamma coincidence technique following the 58Ni(28Si, alpha p)81Y reaction at beam energies of 80-130 MeV. A probable sequence of spins for the states is presented, and these data are compared with systematic trends in this region. The data indicate that the nucleus has a large prolate...

From a study of the 19F(n,gamma) reaction with thermal neutrons incident on a Teflon target, 168 gamma rays have been detected and incorporated into a level scheme of 20F consisting of 35 previously known levels and a new one at 5939 keV. Two low-energy primary E1 transitions of energies 584 and 665 keV together account for more than half of the to...

From a study of the {sup 19}F({ital n},{gamma}) reaction with thermal neutrons incident on a Teflon target, 168 {gamma} rays have been detected and incorporated into a level scheme of {sup 20}F consisting of 35 previously known levels and a new one at 5939 keV. Two low-energy primary {ital E}1 transitions of energies 584 and 665 keV together accoun...

A new calculation of the predominantly isoscalar PNC matrix element between the [ital J][sup [pi]][ital T] 0[sup +]1,0[sup [minus]]1 ([ital E][sub [ital x]][approx]8.7 MeV) states in [sup 14]N has been carried out in a (0+1+2+3+4)[h bar][omega] model space with the Warburton-Brown interaction. The magnitude of the PNC matrix element of 0.22 to 0.54...

Two years ago, a comparison of shell-model predictions with experimental data for first-forbidden β decays in the lead region revealed that the weak rank-zero axial-charge matrix element is enhanced over the impulse approximation value by ≈ 100% as opposed to ≈ 60% in light nuclei. This results was considerably larger than the ≈ 50% enhancement tha...

Calculations are presented for four relatively strong first-forbidden β decays in the region A=11–16 in order to study the very large mesonic-exchange-current enhancement of the rank-zero components. The μ- capture on 16O is considered on the same footing. The wave functions utilized include up to 4ħω excitations. Two-body exchange-current matrix e...

The excited 4+ state at 7117 keV in 18O is studied via the 12C(7Li,pγ)18O reaction. We show that it is highly improbable that the state is energetically degenerate with a state of different decay properties and that its γ decay is consistent with previously reported values. We obtain a γ-branching fraction Γγ/(Γγ+Γα)=0.561±0.013 which together with...

The experimental PNC results in 18 F,19F,21Ne and the actual theoretical analysis1 show a discrepancy (see also Fig. 11 of Ref. 2). If one interprets the small limit of the experimentally extracted PNC matrix element (< 0.029 eV) for 21Ne as a destructive interference between the isoscalar and isovector contributions, then it is difficult to unders...

A comprehensive analysis is made of the experimental information on Gamow-Teller beta decay for the light ([ital A][le]18) nuclei. Experimental data on half-lives, [ital Q] values, and branching ratios are tabulated. Experimental log[ital ft] values and beta-decay matrix elements are deduced from these data. The one-body-transition densities necess...

Mesonic-exchange contributions to the axial charge are evaluated in a shell-model study of the DeltaJ=0 first-forbidden beta- decays of 133Sn(7/2-), 134Sn(0+) and 134Sb(0-). The average enhancement of the axial charge over the impulse approximation is found to be (82+/-7)%. The theoretical value is in the range (58-70)%. Thus there is room for effe...

Shell-model interactions are constructed in the cross-shell model space connecting the 0p and 1s0d shells with due regard for the perturbative effects of the neighboring 0s and 0f1p shells. The interactions have three distinctive 0p-shell, cross-shell, and 1s0d-shell parts. The latter is taken to be the previously determined W interaction. The 0p-s...

A recently constructed shell-model interaction is used to calculate wave functions for the 0+ states of 16O in a six-shell model space. Several different methods of dealing with problems arising from truncation of the model space at 4ħω are described. The preferred is to lower the 4ħω components by the same energy shift as occurs for the ground sta...

The reaction58Ni(36Ar, 4p)90Mo has been studied at a beam energy of 149 MeV. A detector array consisting of the OSIRIS spectrometer (12 Compton-suppressed Ge detectors), four charged-particleδE detectors and seven NE-213 neutron detectors at the VICKSI accelerator in Berlin has been used to measure the gamma radiation inγγ- and particle-γγ-coincide...

Two-shell-model interactions are constructed in the model space of the five proton and six neutron orbits just above the double shell closure at 132Sn. One interaction uses the two-body matrix elements calculated by Kuo and Herling for use near 208Pb. For the other, the proton-proton two-body matrix elements are replaced with effective ones of Krus...

A recent treatment of first-forbidden β- decay in the lead region is extended to β+ decay and electron capture. The modified Kuo-Herling shell-model interaction recently described by Warburton and Brown is used to calculate wave functions and observables for 211Po. The logf0t values for the 211Bi(9/2-)→211Po(9/2+) β- transition and the electron cap...

A shell-model calculation in the model space of the (0d,1s) and (0f,1p) major shells is made for the first-forbidden β- transition 50K(0-)→50Ca(0+). Various truncation schemes were evaluated and the one adopted was to allow at most two neutrons in the ν0f5/2 orbit. An evaluation of the ‘‘final-state’’ core-polarization effects is made perturbativel...

A shell-model study is made of first-forbidden {beta} decay and related processes in {ital A}=205--212 nuclei. The interactions used are modifications of the Kuo-Herling realistic effective interactions for particles above and holes below {sup 208}Pb and a cross-shell {ital G}-matrix interaction connecting these two. Large-scale diagonalizations ar...

Experiments designed to provide more information on the spectroscopy of 214Bi, and on 214Pb(beta-)214Bi in particular, were undertaken because of interest in first-forbidden beta decay in the lead region. The experiments consisted of gamma-gamma coincidences and angular correlations, conversion electron measurements, level lifetime determinations,...

Shell-model calculations are described for {ital A}=204--212 nuclei. These calculations use the Kuo-Herling realistic effective interactions for hole states and particle states relative to {sup 208}Pb. These interactions contain a bare part and a core-polarization contribution. The contribution of the core polarization was varied to find the best f...

The effect of two-particle--two-hole ground-state correlations on spin-dipole transitions and the similar first-forbidden {beta}-decay transitions is studied for nuclei in the lead region with realistic shell-model interactions. Transitions are considered between states for which one is a particle-hole excitation of the other. It is found that the...

Experiments designed to provide more information on the spectroscopy of 214Bi, and on 214Pb(β-)214Bi in particular, were undertaken because of interest in first-forbidden β decay in the lead region. The experiments consisted of γ-γ coincidences and angular correlations, conversion electron measurements, level lifetime determinations, and precision...

Experiments designed to provide more information on the spectroscopy of ²¹⁴Bi, and on ²¹⁴Pb(β⁻)²¹⁴Bi in particular, were undertaken because of interest in first-forbidden β decay in the lead region. The experiments consisted of γ-γ coincidences and angular correlations, conversion electron measurements, level lifetime determinatio...

Rotational bands in the odd-odd nucleus 182Ir and in the odd-mass isotopes 181,183Ir have been studied via the fusion-evaporation reactions 172,174Yb(14N,xn) utilizing gamma-ray spectroscopy techniques. The different band structures in 182Ir are interpreted as specific couplings of proton and neutron single-quasiparticles present in neighboring odd...

The first postulation of excited states in neutron-rich 76Zn is presented. We postulate the levels in 76Zn to be populated by high- and low-spin isomers of 76Cu with half-lives of 0.57 s and 1.27 s, respectively. Of 12 gamma rays attributed to 76Zn decay, 11 are placed in a level scheme for 76Zn with eight excited states up to 3 MeV. A shell-model...

Lifetimes of T1/2=88(3) and 291(11) ps were measured for the 0+2 states and T1/2=102(3) and 500(13) ps for the 4+1 states in 92.94Zr, respectively, using a recently developed beta-gamma-gamma fast timing method. The observed B(E2) values and the recently measured g factors for the 2+1 states in 92,94Zr deviate strongly from properties of a pure nu1...

Further evidence for the presence of an anomaly in binding energies for the ``island of inversion'' centered at Z=11, N=21 is obtained by comparison of shell-model calculations to experiment. The calculations were done with a shell-model interaction that is applicable to nuclei with active valence nucleons in both the (1s,0d) and (0f,1p) major shel...

In this paper we review the progress of the shell-model approach to understanding the properties of light exotic nuclei (A < 40). By shell-model'' we mean the consistent and large-scale application of the classic methods discussed, for example, in the book of de-Shalit and Talmi. Modern calculations incorporate as many of the important configuratio...

Shell-model calculations are performed for the odd- and even-parity states of 39Cl and the odd-parity states of 39S. The 39S odd-parity states and the 39Cl even-parity states were considered in full (1s,0d)20(0f,1p)3 and (1s,0d)21(0f,1p)2 configurational spaces, respectively. For the 39Cl odd-parity states it was necessary to use a highly truncated...

A reexamination of the gamma-ray spectrum of 56Co has revealed a previously unobserved transition of 852.78(5) keV decaying with the 56Co half-life. Its intensity is 0.050(3) relative to I847=100. Alternate explanations for this peak, such as summing, have been ruled out and the gamma ray is assigned as the 4298.0(4+)-->3445.3(3+) transition in 56F...

We have investigated the 0- 96Yg β decay to the levels of 96Zr. A detailed decay scheme comprised of 63 γ rays and 44 energy levels has been obtained from γ singles, γ multispectral scaling, and γ-γ and E0-γ coincidences. Qβ was measured using the β-γ coincidence technique, while absolute E0 and γ-ray intensities were obtained from singles conversi...

The magic numbers Z=28 and N=50 imply that very neutron-rich ⁷⁸Ni, which has not yet been observed, is doubly magic. The ⁷⁸Ni region was investigated by studying the N=50 isotones and neutron-rich Zn isotopes. Results on the level structure of ⁸³As, ⁷⁴Zn, and ⁷⁶Zn populated in the decays of ⁸³Ge, ⁷⁴Cu, and ⁷⁶Cu are pre...

The first postulation of excited states in neutron-rich ⁷⁶Zn is presented. We postulate the levels in ⁷⁶Zn to be populated by high- and low-spin isomers of ⁷⁶Cu with half-lives of 0.57 s and 1.27 s, respectively. Of 12 γ rays attributed to ⁷⁶Zn decay, 11 are placed in a level scheme for ⁷⁶Zn with eight excited states up to 3 Me...

Rotational bands in the odd-odd nucleus 182Ir and in the odd-mass isotopes 181,183Ir have been studied via the fusion-evaporation reactions 172,174Yb( 14N, xn) utilizing gama-ray spectroscopy techniques. The different band structures in 182Ir are interpreted as specific couplings of proton and neutron single-quasiparticles present in neighboring od...

Lifetimes of {ital T}ââ=88(3) and 291(11) ps were measured for the 0â{sup +} states and {ital T}ââ=102(3) and 500(13) ps for the 4â{sup +} states in {sup 92.94}Zr, respectively, using a recently developed β-γ-γ fast timing method. The observed {ital B}({ital E}2) values and the recently measured {ital g} factors for the 2â{sup +} states in {...

We have investigated the 0⁻ ⁹⁶Y{sup {ital g}} β decay to the levels of ⁹⁶Zr. A detailed decay scheme comprised of 63 γ rays and 44 energy levels has been obtained from γ singles, γ multispectral scaling, and γ-γ and {ital E}0-γ coincidences. {ital Q}{sub β} was measured using the β-γ coincidence technique, while absolute {ital E...

The half-life of 56Co has been determined in one series of experiments by simultaneously measuring the decay of the 847-keV γ-ray line relative to the 662-keV line of 137Cs and the decay of the 1238-keV line relative to the 1275-keV line of 22Na in a Ge(Li) γ-ray detector. Data were taken for two half-lives of 56Co. In a second series of runs, cove...

The first information on excited states in neutron-rich /sup 74/Zn populated in the ..beta.. decay of /sup 74/Cu is presented. The /sup 74/Cu half-life was measured to be 1.59 +- 0.05 s. On the basis of ..gamma.. singles and coincidence measurements, a total of 19 ..gamma.. rays were placed in a level scheme for /sup 74/Zn with 10 excited states up...

Shell-model calculations are performed for the odd- and even-parity states of 40Cl and the 0+ 40S ground state. The 40Cl odd-parity states and the 40S 0+ levels were considered in full (2s,1d)21(1f,2p)3 and (2s,1d)20(1f,2p)4 configurational spaces, respectively. For the 40Cl even-parity states it was necessary to use a highly truncated (2s,1d)20(1f...

The energy spectra and wave functions of 17C and 17N are calculated using a modification of the Millener-Kurath interaction. The results are used to predict the half-life and decay modes of both the allowed and first-forbidden beta- decays of 17C as well as 18O(d,3He)17N spectroscopic factors and electromagnetic transition rates in 17N.

The beta- decay of 22 h 43K (Jpi=(3/2+) was reexamined with the main motive of determining the first-forbidden beta- branches to the (3/2- and (5/2- states more accurately. The branch to the (5/2- state at 373 keV was established as 0.9(6)% as opposed to a previous limit of

The half-life of ⁵⁶Co has been determined in one series of experiments by simultaneously measuring the decay of the 847-keV γ-ray line relative to the 662-keV line of ¹³⁷Cs and the decay of the 1238-keV line relative to the 1275-keV line of ²²Na in a Ge(Li) γ-ray detector. Data were taken for two half-lives of ⁵⁶Co. In a second seri...

A reexamination of the γ-ray spectrum of ⁵⁶Co has revealed a previously unobserved transition of 852.78(5) keV decaying with the ⁵⁶Co half-life. Its intensity is 0.050(3) relative to {ital I}âââ=100. Alternate explanations for this peak, such as summing, have been ruled out and the γ ray is assigned as the 4298.0(4+){r arrow}3445.3(3+) tr...

The - decay of 22 h K43 (J=(3/2+) was reexamined with the main motive of determining the first-forbidden - branches to the (3/2- and (5/2- states more accurately. The branch to the (5/2- state at 373 keV was established as 0.9(6)% as opposed to a previous limit of <3%. Other - and branching ratios and -ray energies were determined with considerably...

We report on the first in-beam study of high spin levels in83Y which were established up to 9.0 MeV excitation energy and probable spin of 41/2+ resp. 27/2− by means of the reaction58Ni(28Si, 3p). Ten lifetimes and six lifetime limits in the 10−12–10−9 s range were determined in two recoil distance Doppler shift experiments. The positive parity yra...

44Ti(EC)44Sc was studied both experimentally and theoretically. The experimental study-motivated by current interest in first-forbidden beta decay-leads to more precise branching ratios for the electron capture decay to the 0- and 1- levels of 44Sc as well as to other ancillary results including precision gamma-ray energy determinations, gamma-ray...

Shell model calculations in the full sdpf model space are carried out for the known and possible first-forbidden beta decays for 34 < A < 44. The main purpose is to study the strong quenching of the unique (ΔJ = 2) decays, which results from the repulsive nature of the T = 1 particle-hole interaction, and the strong meson-exchange enhancement of th...

States of 184Ir, excited through several (HI, xn) reactions were studied using in-beam gamma-ray and conversion electron spectroscopy techniques. A new high-spin level scheme, comprising three different rotational bands is presented. The negative-parity DeltaI = 1 ground-state band is the most complete example of the semidecoupled \~gph9/2⊗ v~i13/2...

The energies of 16 gamma-rays from 56Co decay were determined with a Ge(Li) Compton suppression spectrometer. The mixed source technique was used with gamma-ray energy standards provided by 110mAg, 124Sb, 182Ta, and 144Ce beta-decay. The main motive for these measurements was to obtain more precise energies for transitions with energies in the 2500...

A many-level, many-channel R-matrix formula is used to fit the measured 8He β-decay data, including the half-life, branching ratios and delayed neutron and triton energy spectra. Satisfactory fits are found with contributions from four 1+ levels of 8Li, at 0.98, 3.08, 5.15 and 9.06 MeV. The 32 reduced width amplitudes are taken from a shell-model c...

The energy spectra and wave functions of 19N and 19O are calculated using a modification of the Millener-Kurath interaction. The results are used to predict the half-life and decay modes of both the allowed and first-forbidden β- decays of 19N. Comparison is made to recent experiments.

The nuclear structure of the parent and daughter nuclei in the decays 34Al(β-)34Si, 36Si(β-)36P, and 37P(β-)37S are considered in a spherical shell model comprising the (2s,1d,1f,2p) configuration space. Energy spectra and beta and gamma transition strengths are calculated. These predictions are used to construct decay schemes from recent β--delaye...

The energies and intensities of gamma rays from the decay of 87Y(t12/=79.8 h), produced in the 87Sr(p,n) reaction at Ep=18 MeV, were measured with a Ge(Li) detector. Precision energy values of 388.531(3) and 484.805(5) keV were determined for the two 87Y gamma rays using the mixed source technique. The intensity ratio of the 485 and 389 keV gamma r...

We present a level spectrum for 219Ra derived from data on the reaction 208Pb(14C,3n) studied at beam energies near the Coulomb barrier. Measurements of γ-ray excitation functions, γ-γ coincidences, γ-ray angular distributions, and electron conversion coefficients were made. The ground state band shows an alternating parity structure and is consist...

The low-spin ..beta..-decay of /sup 96,98/Y has been reinvestigated to obtain detailed informatin on the fast first-forbidden transitions to the ground states of /sup 96,98/Zr. A considerably more detailed decay scheme of /sup 96/Y confirms the general features of a previous study. The spin of the ground state of /sup 98/Y has been measured to be 0...

The electromagnetic deexcitation of the six known 14C+α resonances in the range Eα=1.7–2.7 MeV was observed with a Ge(Li) detector. Results for the branching ratios of the 7.62-, 8.04-, and 8.13-MeV 18O levels were found to be in agreement with previous measurements. Deexcitation of the 7.86-, 8.21-, and 8.28-MeV levels was observed for the first t...

The precision energies and relative intensities of 11 γ transitions from the decay of 134Cs have been determined. 192Ir, 228Th, 137Cs, 110mAg, 60Co, and 207Bi served as energy calibration standards, and 152Eu and 192Ir as relative intensity calibration standards. Special care was taken in the analysis of data for the weaker transitions. The results...

The electromagnetic deexcitation of the six known /sup 14/C+..cap alpha.. resonances in the range E/sub ..cap alpha../ = 1.7--2.7 MeV was observed with a Ge(Li) detector. Results for the branching ratios of the 7.62-, 8.04-, and 8.13-MeV /sup 18/O levels were found to be in agreement with previous measurements. Deexcitation of the 7.86-, 8.21-, and...

γ-γ coincidence measurements were made following the formation of 38S via the 36S(t,pγ)38S reaction at Et=3.2 MeV. Gamma-ray spectra gated on the full-energy peak of the 1292-keV γ ray from the decay of the first-excited state clearly showed both 1513- and 1533-keV γ rays, thus confirming the existence of the probable 2805-keV level reported recent...

The β decay of 39Cl, produced in the 37Cl(t,p)39Cl reaction at Et=3.1 MeV, has been investigated with a Ge-NaI(Tl) Compton-suppression γ-ray spectrometer. Nineteen γ-ray transitions were observed, including 10 previously known. Precision energy measurements were carried out on six of the strongest lines. In the proposed decay scheme a weak new β-ra...

A spherical shell-model calculation of the odd- and even-parity states of 39Ar is made in a full sdpf model space. The calculation includes absolute binding energies and energy spectra, single-neutron spectroscopic factors, and electromagnetic and beta decay observables. Agreement with experiment is fairly good. Comparison is hampered by incomplete...

The nuclear structure of the N=21 isotones 35Si and 36P and the N=20 isotones 35P and 36S is considered in the spherical nuclear shell model with the SDPF interaction. Beta and gamma decay as well as energy spectra are calculated. Results are compared to recent data on 36P(beta-)36S and 35Si(beta-)35P. Unique and nonunique first-forbidden beta deca...

We report the results of a study of the yrast excitation spectrum for 216Rn via the 208Pb(14C,α2n)216Rn reaction. Measurements of γ-γ coincidences, γ-ray angular distributions, and γ-x-ray coincidences were made. We propose a level spectrum up to Jπ=(10+) which does not exhibit the alternating parity structure observed in several isotopes of radium...

The ..beta.. decay of /sup 39/Cl, produced in the /sup 37/Cl(t,p)/sup 39/Cl reaction at E/sub t/ = 3.1 MeV, has been investigated with a Ge-NaI(Tl) Compton-suppression ..gamma..-ray spectrometer. Nineteen ..gamma..-ray transitions were observed, including 10 previously known. Precision energy measurements were carried out on six of the strongest li...

20O was produced in the reaction 18O(18O, 16O)20O and its half-life measured by observing the decay of the 1.06-MeV gamma transition in 20F in a Ge-Li counter. The result is t12=13.57+/-0.1 sec, ft=3.73. Upper limits were obtained for weak beta-decay branches of 20O to other states in 20F between Ex=0.984 and 2.195 MeV.

Gamma rays from the decay of O20, produced in the O18(t,p)20O reaction at Et=3.1 MeV using a Van de Graaff beam and a rabbit target-transfer system, were measured in a Ge-NaI(Tl) Compton-suppression spectrometer. In addition to the principal ray, measured as 1056.818(4) keV, a ray of 3488.21(10) keV was observed with an intensity corresponding to a...

The 36S(t,pγ) 38S reaction was used to populate levels in 38S up to 3-MeV excitation. A definite 2+ assignment to the 1292-keV first-excited state was obtained from a (t,pγ) angular correlation. Doppler shift information provided lower limits of 0.45 and 0.2 ps for the mean lifetimes of the 1291→0 and 2825→1291 transitions. Evidence for a possible...

The energies of 29 gamma rays from the decay of 152Eu have been determined in order to provide calibration energies for Ge gamma-ray spectrometers. Particular emphasis is placed on those gamma transitions resulting from the decay of the 152Sm 1530 keV level. A least-squares adjustment to these 152Sm gamma transitions results in a set of recommended...

Conventional spherical shell model calculations have been undertaken to describe 90,88Zr and 90,88Y. In these large scale calculations valence orbitals included 1f5/2,2p3/2,2p1/2, and 1g9/2. The d5/2 orbital was included for 90Y and for high-spin calculations in 90Zr. Restrictions were placed on orbital occupancy so that the basis set amounted to l...

The ..beta../sup -/ decays of /sup 35/P, /sup 37/S, /sup 38/S, and /sup 38/Cl were studied both experimentally and via shell-model calculations. The four decaying nuclei were formed by bombardment of 81% enriched /sup 36/S by triton and deuteron beams. Gamma-ray spectroscopy was carried out with Ge detectors, either bare or surrounded by a Compton...

A search for structures in which both valence neutron and proton occupy predominantly Omega=(1/2) orbits, called doubly decoupled, has been successfully conducted in 182,184Ir. These evaporation residues were populated through the 172,174Yb(14N,4n) fusion reactions and studied using gamma-ray spectroscopy techniques.

A search for structures in which both valence neutron and proton occupy predominantly ..cap omega.. = (1/2) orbits, called doubly decoupled, has been successfully conducted in /sup 182,184/Ir. These evaporation residues were populated through the /sup 172,174/Yb(/sup 14/N,4n) fusion reactions and studied using ..gamma..-ray spectroscopy techniques.

36S(14C,xnypzαγ) reactions were used to extend our knowledge of the high-spin states of 47Ti, 47Sc, 44Ca, 45Ca, and 48Ti. The decay schemes were constructed from γγ-coincidence data and γ-ray angular distributions and excitation functions. The angular distributions also provided information on spin-parity assignments and multipole mixing ratios. Li...

36S(14C,xnypzαγ) reactions were used to extend our knowledge of the high-spin states of 47Ti, 47Sc, 44Ca, 45Ca, and 48Ti. The decay schemes were constructed from γγ-coincidence data and γ-ray angular distributions and excitation functions. The angular distributions also provided information on spin-parity assignments and multipole mixing ratios. Li...

Excited states in 195Bi were populated by the 182W(19F,6n) and 169Tm(30Si,4n) reactions. The subsequent γ-ray emission was studied using in-beam spectroscopic methods including excitation functions, γ-ray angular distributions, γ-γ-t coincidence, conversion electron, and pulsed-beam-γ timing measurements. Three isomeric states were located in 195[J...

The level scheme of 219Ra established via a study of the 208Pb(14C,3n)219Ra reaction is presented. The structure of the rotational band based on the ground state is interpreted as reflecting a g9/2 valence neutron weakly coupled to a spherical 218Ra core. A non-yrast side band is observed, having tentative (11/2)-, (15/2)-, . . . level assignments....

The properties of high-spin states in 197Bi have been studied with the 192Pt(10B,5n)197Bi reaction at 10B energies between 50 and 80 MeV. In-beam measurements of gamma-ray excitations, gamma-gamma-t coincidences, gamma-ray angular distributions, and pulsed-beam-gamma timing were performed with Ge detectors to determine level energies, decay schemes...

A level scheme for Ra220 is presented, established using the C208,2n) reaction studied near the Coulomb barrier (60E 68 MeV). Measurements included -ray excitation functions, - coincidences, and -ray angular distributions. The dominant features in the spectrum are states of alternating parity connected by fast E1 transitions. Values of B(E1)/B(E2)...

The properties of high-spin states in 197Bi have been studied with the 192Pt(10B,5n)197Bi reaction at 10B energies between 50 and 80 MeV. In-beam measurements of γ-ray excitations, γ-γ-t coincidences, γ-ray angular distributions, and pulsed-beam-γ timing were performed with Ge detectors to determine level energies, decay schemes, γ-ray multipolarit...

A level scheme for /sup 220/Ra is presented, established using the /sup 208/Pb( /sup 14/C,2n) reaction studied near the Coulomb barrier (60< or =E< or =68 MeV). Measurements included ..gamma..-ray excitation functions, ..gamma..-..gamma.. coincidences, and ..gamma..-ray angular distributions. The dominant features in the spectrum are states of alte...

The 36S(t,p)38S reaction was studied at 18-MeV bombarding energy with an overall energy resolution of 55 keV. Excited states of 38S were identified at energies (uncertainties in parentheses) of 1295(10), 2835(14), 3375(17), 3690(17), 4336(20), 4478(22), 4955(25), 5064(27), 5278(28), 6000(30), and 6605(60) keV. Angular distributions were measured fo...

A particle-gamma coincidence experiment following the sup62Ni(sup27Al,xnypz..cap alpha gamma..) fusion-evaporation reaction was performed to decide between two alternative proposals for the sup86Y yrast decay scheme. The results verify the scheme found via the sup76G+ sup14N and sup73Ge+ sup16O reactions. It is suggested that the decay scheme seen...

The properties of high-spin states in 199,201Bi have been studied with the 194,196Pt(10B,5nγ )199,201Bi reactions at energies between 57 and 72 MeV. In-beam measurements of γ-ray excitations, γ-γ-t coincidences and correlations, γ-ray angular distributions, and pulsed-beam-γ timing were performed with Ge detectors to determine level energies, decay...

The properties of high-spin states in /sup 199,201/Bi have been studied with the /sup 194,196/Pt(¹°B,5n..gamma.. ) /sup 199,201/Bi reactions at energies between 57 and 72 MeV. In-beam measurements of ..gamma..-ray excitations, ..gamma..-..gamma..-t coincidences and correlations, ..gamma..-ray angular distributions, and pulsed-beam-..gamma.. timin...

The level scheme of 86Zr was studied by in-beam measurements on γ transitions in the 60Ni(29Si,2pnγ)86Zr reaction and by helium-jet studies of delayed γ-ray activity from the 58Ni(32S,3pn)86Nb(β +/EC)86Zr reaction. In the latter study, measurements consisted of γ-γ and β-γ coincidences, excitation functions, and a lifetime determination. An 86Nb de...

The high-spin states of 88Zr and 90Zr were studied up to ∼12-MeV excitation via the 74,76Ge(18O,4nγ)8 8,90Zr fusion evaporation reactions. Decay schemes were constructed on the basis of gamma-ray excitation functions, angular distribution and linear polarization measurements, γ-γ coincidences, and level lifetimes determined from both Doppler shift...

The level scheme of 220Ra, constructed from 208Pb(14C, 2nγ)220Ra data, shows structure similar to that of 218Ra, with interleaved states of alternating parities connected by enhanced B (E 1) deexcitations. The B (E 1)B (E 2) ratios (for moderately high spins) are two to three times smaller than in 218Ra; we observe a smooth and rapid increase of th...

The S36(d,p)S37 reaction was studied at Ed=25 MeV with an enriched S36 target (81.1%) and momentum analysis of the protons. Twenty-six groups were identified with levels in S37. Excitation energies were obtained with an uncertainty of ns yielded l and S values for the transfer reaction. Comparison is made to local systematics and the l=1 strength i...

Gamma rays from the decays of Sc50, Scm50, Ca50, and K47, produced by Ca48+t reactions at Et=3.2 MeV, were investigated with a Ge(Li) detector. A 3.5-MV Van de Graaff and a "rabbit" target-transfer system were used. Precision energy measurements resulted in the following -ray energies (in keV): Sc50, 523.792(18), 1121.124(5), and 1553.768(8); Ca50,...

The 16N and 15C spectra measured by Alburger, Gallmann, and Wilkinson were reanalyzed to obtain more accurate branching ratios as well as a shape factor for the first-forbidden, nonunique 15C(1/2+)→15N(1/2-) decay. 16N β- branches were derived to the levels at 0 and 6.13 MeV of 27.9(5)% and 66.3(6)%, respectively; 15C β- branches were found to 15N...

A 4.25-kg sample of vanadium metal was counted with a high purity Ge detector for 135.5 d. Ninety-six peaks were observed in the ..gamma..-ray spectrum between 220 and 2615 keV, all but one of which could be assigned to known contaminant radioactivities mostly contained in the V sample itself. After making a 4.0% calculated correction for the inten...

A. 4.25-kg sample of vanadium metal was counted with a high purity Ge detector for 135.5 d. Ninety-six peaks were observed in the γ-ray spectrum between 220 and 2615 keV, all but one of which could be assigned to known contaminant radioactivities mostly contained in the V sample itself. After making a 4.0% calculated correction for the intensity of...

A. 4.25-kg sample of vanadium metal was counted with a high purity Ge detector for 135.5 d. Ninety-six peaks were observed in the -ray spectrum between 220 and 2615 keV, all but one of which could be assigned to known contaminant radioactivities mostly contained in the V sample itself. After making a 4.0% calculated correction for the intensity of...