Recent Articles

Double positron-electron pair production by 6.6-MeV gamma rays

A. Robertson, T. J. Kennett, and W. V. Prestwich

Phys. Rev. C 13, 1552 (1976) - Published 1 April, 1976

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Double positron-electron pair production by 6.6-MeV $γ$ rays was investigated via measurement of fourfold coincidence rates of annihilation quanta in targets of beryllium, boron, carbon, aluminum, sulphur, copper filings, and solid copper. Following an accounting for the interfering bremsstrahlung-cascade and direct-cascade effects a measure of the cross section for the process, relative to that for single-pair production, was obtained as $\frac{σ_{π π}}{σ_{π}} = (1.82 \pm 0.58) \times 10^{- 5}$ .

NUCLEAR REACTIONS Measured $σ$ for double-pair production at 6.6 MeV.

Prompt gamma rays from nuclear reactions induced by 380-MeV $π$

R. E. Segel, L. R. Greenwood, P. Debevec, H. E. Jackson, D. G. Kovar, L. Meyer-Schützmeister, J. E. Monahan, F. J. D. Serduke, T. P. Wangler, W. R. Wharton, and B. Zeidman

Phys. Rev. C 13, 1566 (1976) - Published 1 April, 1976

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Using a Ge(Li) detector, $γ$ -ray spectra coincident with incident 380-MeV $π^{-}$ have been measured for targets of S, Ar, Ca, V, ${}^{60}{Ni}$ , and As. The production cross sections for identified $γ$ rays vary from about 200 to about 500 mb, depending on the target, although there is considerable uncertainty in the absolute cross sections. Comparison with data taken at lower energies leads to the conclusion that the spectra do not significantly change with pion energy over the range $100 MeV \leq T_{π} \leq 400 MeV$ . Formation of nuclei which can be made by removing an integral number of $α$ particles, or, in the case of odd targets, a triton plus an integral number of $α$ particles, appears to be usually favored but it is not certain that it is necessary to invoke special clustering effects in order to explain the presently available data. Some clues as to the reaction mechanism can be found in the data.

NUCLEAR REACTIONS 380-MeV $π^{-}$ on S, Ar, Ca, V, ${}^{60}{Ni}$ , As. Measured $γ$ -ray spectra, cross sections.

Decays of ${}^{88}{Kr}$ and ${}^{88}{Rb}$

R. L. Bunting, W. L. Talbert, Jr., J. R. McConnell, and R. A. Meyer

Phys. Rev. C 13, 1577 (1976) - Published 1 April, 1976

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The $γ$ rays following the $β$ decays of ${}^{88}{Kr}$ and ${}^{88}{Rb}$ have been studied, using both large volume Ge(Li) detectors for singles and coincidence measurements and anti-Compton spectrometry for singles measurements. Level schemes for ${}^{88}{Rb}$ and ${}^{88}{Sr}$ were constructed from the data and 74 of 81 $γ$ rays observed in the decay of ${}^{88}{Kr}$ were placed in the ${}^{88}{Rb}$ level scheme with 23 excited states. For the decay of ${}^{88}{Rb}$ , all of the observed 27 $γ$ rays have been placed in the (well known) level structure of ${}^{88}{Sr}$ . Spin and parity assignments have been deduced from $β$ -decay $log ft$ values and $γ$ -ray transition patterns. Possible shell-model interpretations are presented for the level schemes.

RADIOACTIVITY ${}^{88}{Kr}$ , ${}^{88}{Rb}$ [from ${}^{235}U (n, f)$ ]; measured $E_{γ}$ , $I_{γ}$ , $γ - γ$ coin. Ge(Li) detectors, Compton suppression. ${}^{88}{Rb}$ , ${}^{88}{Sr}$ deduced levels, $J$ , $π$ , $log ft$ . Mass-separated ${}^{88}{Kr}$ activity.

Structure of $N = 81$ nuclei: Levels of ${}^{141}{Nd}$ and ${}^{139}{Ce}$ populated in beta decay

M. R. Zalutsky, E. S. Macias, and R. A. Meyer

Phys. Rev. C 13, 1590 (1976) - Published 1 April, 1976

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The nuclear level structure of ${}^{141}{Nd}$ and ${}^{139}{Ce}$ has been investigated by studying the decay of 20.9-min ${}^{141}{Pm}$ produced via the ${}^{141}\Pr ({}^{3}{He}, 3 n)$ reaction and the decay of 4.5-h ${}^{139}\Pr$ produced by the ${}^{140}\Pr (γ, n) {}^{139}\Pr$ reaction. For the ${}^{141}{Pm}$ decay, singles and anti-Compton $γ$ -ray spectra and $γ - γ$ coincidence measurements were used to deduce a decay scheme that includes nine previously unreported levels in ${}^{141}{Nd}$ and incorporates 67 of the 70 $γ$ rays attributed to the decay of ${}^{141}{Pm}$ . Singles and anti-Compton spectra were taken as a function of time in order to confirm assignment of the ${}^{139}\Pr$ $γ$ rays. The level structures of ${}^{141}{Nd}$ and ${}^{139}{Ce}$ are compared to recent measurements in other $N = 81$ isotones. The results of this work are in good agreement with theoretical predictions based on the hole-vibrational coupling model for levels below 1.3 MeV. There exist more levels between 1.3 and 2.0 MeV than are predicted by this model, but these excess levels can be explained qualitatively within a weak coupling framework.

RADIOACTIVITY ${}^{141}{Pm}$ [from ${}^{141}\Pr ({}^{3}{He}, 3 n)$ ] and ${}^{139}\Pr$ [from ${}^{140}\Pr (γ, n)$ ] measured $E_{γ}$ , $I_{γ}$ , $γ - γ$ coin; deduced ${}^{141}{Nd}$ and ${}^{139}{Ce}$ levels, $J$ , $π$ , and $log ft$ values. Natural target, Ge(Li) detectors, anti-Compton spectrometer.

On-line mass separator investigation of the new isotope 2.9-sec ${}^{116}I$

G. M. Gowdy, A. C. Xenoulis, J. L. Wood, K. R. Baker, R. W. Fink, J. L. Weil, B. D. Kern, K. J. Hofstetter, E. H. Spejewski, R. L. Mlekodaj, H. K. Carter, W. D. Schmidt-Ott, J. Lin, C. R. Bingham, L. L. Riedinger, E. F. Zganjar, K. S. R. Sastry, A. V. Ramayya, and J. H. Hamilton

Phys. Rev. C 13, 1601 (1976) - Published 1 April, 1976

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Using on-line mass separation ${}^{116}I$ has been identified and its half-life determined to be 2.91 ± 0.15 sec. The activity was produced by the ${}^{103}{Rh} ({}^{16}O, 3 n) {}^{116}I$ reaction and by the decay of 57-sec ${}^{116}{Xe}$ . The ${}^{116}I$ decays primarily to the ground state of ${}^{116}{Te}$ and also to excited states at 678.9 and 1219.1 keV. From positron measurements, a decay energy of $Q_{EC} = 7.71 \pm 0.20$ MeV is assigned to ${}^{116}I$ . $γ$ rays of 540.2 and 678.9 keV are observed in this decay and are assigned to depopulate levels in ${}^{116}{Te}$ at 1219.1 and 678.9 keV, respectively. The former is a new level with a probable spin-parity of either $2^{+}$ or $0^{+}$ . From the $log ft$ values, a spinparity assignment of $1^{+}$ is deduced for the ground state of ${}^{116}I$ , which is interpreted to have a configuration of [ $π (d_{\frac{5}{2}}) ν (d_{\frac{3}{2}})$ ]. A decay energy of $Q_{EC} = 4.34 \pm 0.20$ MeV observed from activity produced by the ${}^{104}{Pd}$ + ${}^{16}O$ reaction is assigned to ${}^{116}{Xe}$ .

NUCLEAR REACTIONS ${}^{103}{Rh} ({}^{16}O, 3 n γ)$ , $E = 83$ MeV; ${}^{104}{Pd} ({}^{16}O, 4 n γ)$ and ${}^{104}{Pd} ({}^{16}O, p 3 n γ)$ , $E = 91$ MeV. Natural Rh targets and enriched Pd targets. RADIOACTIVITY ${}^{116}I$ , ${}^{116}{Xe}$ ; measured $E_{γ}$ , $I_{γ}$ , $T_{\frac{1}{2}} (γ)$ , $T_{\frac{1}{2}} (β^{+})$ , $β^{+} - γ$ coin., $β^{+}$ end point; ${}^{116}{Te}$ deduced levels, $J$ , $π$ , $log ft$ ; ${}^{116}I$ deduced ground state $J$ , $π$ , $log ft$ ; Ge(Li) detectors and plastic scintillators; mass separated sources.

Isomerism in the $N = 81$ isotope ${}^{147}{Dy}$

A. E. Rainis, K. S. Toth, and C. R. Bingham

Phys. Rev. C 13, 1609 (1976) - Published 1 April, 1976

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With the use of a helium-gas-jet capillary transport system a new (59±3)-sec activity was observed in ${}^{14}N$ bombardments of ${}^{141}\Pr$ . The activity was found to be associated with two coincident $γ$ rays, 72.0 ± 0.1 and 678.7 ± 0.2 KeV. The 678.7-keV transition was also observed to be in coincidence with dysprosium $K$ x rays and its yield as a function of bombarding energy varied in the same manner as $γ$ rays known to follow the decay of 1.9-min ${}^{147}{Tb}$ . From these results we conclude that the new activity is ${}^{147}{Dy}^{m}$ and that the 72.0- and 678.7-keV $γ$ rays represent transitions in ${}^{147}{Dy}$ . Further, based on the systematic behavior of low-lying levels in $N = 81$ odd- $A$ nuclei, we propose that our data establish the $h_{\frac{11}{2}}$ and $d_{\frac{3}{2}}$ neutron states in ${}^{147}{Dy}$ to be 750.7 and 72.0 keV, respectively, above the $s_{\frac{1}{2}}$ ground state.

RADIOACTIVITY ${}^{147}{Dy}^{m}$ , ${}^{145}{Dd}^{m}$ ; measured $T_{\frac{1}{2}}$ , $E_{γ}$ , $I_{γ}$ , $γ γ$ coin. Observed isotope ${}^{147}{Dy}$ . ${}^{147}{Dy}$ , ${}^{145}{Gd}$ ; deduced levels, $j^{π}$ .

Three-particle one-hole configurations in odd-odd ${}^{134}I$ and the decay of ${}^{134}{Te}$

R. A. Meyer, J. H. Landrum, S. V. Jackson, W. H. Zoller, and W. B. Walters

Phys. Rev. C 13, 1617 (1976) - Published 1 April, 1976

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The levels of ${}^{134}I$ have been studied by singles and coincidence Ge(Li) spectrometers. To obtain 42-min ${}^{134}{Te}$ free from its daughter, 52.8-min ${}^{134}I$ , $γ - γ$ coincidence data were taken with ${}^{134}{Te}$ adhered to an ion exchange column while its daughter was being continually eluted. Levels were identified at ( $J^{π}$ in parentheses) ground state ( $4^{+}$ ), [44.4 ( $5^{+}$ )], 79.445 ( $3^{+}$ ), 181.89 [ $3^{+}$ ( $2^{+}$ )], 210.47 [ $2^{+}$ ( $3^{+}$ )], 645.44 ( $2^{+}$ ), 846.65 ( $1^{+}$ ), 923.51 ( $1^{+}$ ), and 1107.44 keV ( $1^{+}$ ). The levels are discussed within the framework of three-proton-particle one-neutron-hole configurations.

RADIOACTIVITY Measured $E_{γ}$ , $I_{γ}$ , $γ - γ$ coincidence; deduced ${}^{134}I$ levels; activity isolated from fission, sources measured while daughter product continually eluted from ion-exchange column.

Gamma-gamma angular correlations in ${}^{105}{Rh}$ following the decay of 4.4-h ${}^{105}{Ru}$

E. W. Schneider, G. J. Mathews, S. V. Jackson, P. W. Gallagher, and W. B. Walters

Phys. Rev. C 13, 1624 (1976) - Published 1 April, 1976

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$γ - γ$ angular correlations have been measured for the 349-149-, 575-149-, 393-262-, 414-262-, 350-326-, and 316-469-keV cascades in ${}^{105}{Rh}$ following the decay of 4.4-h ${3 / 2}^{+}$ ${}^{105}{Ru}$ . A ${3 / 2}^{+}$ spin and parity assignment is established for the 806-keV level and ${1 / 2}^{+}$ or ${5 / 2}^{-}$ values found consistent for the 786-keV level with ${1 / 2}^{+}$ favored. For the 149-keV transition, a $δ$ value of 0.4±0.1 is deduced. Possible configuration for the 786-keV level are discussed.

RADIOACTIVITY ${}^{105}{Ru}$ ; measured $γ γ (θ)$ ; deduced $A_{22}$ , $A_{44}$ . ${}^{105}{Rh}$ deduced $J$ , $π$ for 806, 786-keV levels.

Level schemes of ${}^{91}{Rb}$ and ${}^{91}{Sr}$ populated in beta decay

M. D. Glascock, W. L. Talbert, Jr., and C. L. Duke

Phys. Rev. C 13, 1630 (1976) - Published 1 April, 1976

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The decays of mass-separated ${}^{91}{Kr}$ and ${}^{91}{Rb}$ have been studied using $γ$ -ray singles and coincidence techniques. From the decay of ${}^{91}{Kr}$ , a level scheme is proposed for ${}^{91}{Rb}$ consisting of 60 excited states and accommodating 218 of the 220 observed transitions. The half-life of the 108.8-keV level of ${}^{91}{Rb}$ has been determined to be 0.8 ± 0.3 nsec by delayed coincidence techniques. From the decay of ${}^{91}{Rb}$ , 109 of the 125 observed transitions are placed in a level scheme for ${}^{91}{Sr}$ containing 37 excited states. The half-life of the 93.6-keV level in ${}^{91}{Sr}$ has been measured to be 87.5 ± 3.0 nsec. Ground-state $β$ branching has been determined to be (10 ± 4)% and (5 ± 5)% for the decays of ${}^{91}{Kr}$ and ${}^{91}{Rb}$ , respectively. Some spin-parity assignments are made, and a shell-model interpretation is suggested for some of the levels.

RADIOACTIVITY ${}^{91}{Kr}$ , ${}^{91}{Rb}$ [from ${}^{235}U (n, f)$ ]; measured $E_{γ}$ , $I_{γ}$ , $γ - γ$ coin, delayed coin, deduced g.s. $β$ branch, $log ft$ . ${}^{91}{Rb}$ , ${}^{91}{Sr}$ deduced levels, $J$ , $π$ , $T_{\frac{1}{2}}$ . Mass-separated ${}^{91}{Kr}$ activity.

Distribution of electrical charge in the nucleus of ${}^{181}{Ta}$

D. McLoughlin, S. Raboy, E. Deci, D. Adler, R. Sutton, and A. Thompson

Phys. Rev. C 13, 1644 (1976) - Published 1 April, 1976

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The $K$ and $L$ transitions of muonic atoms of ${}^{181}{Ta}$ were measured. A comparison of the experimental values with calculated values was made. A modified Fermi distribution of charge of three parameters was assumed for the calculation. The calculations include corrections for nuclear polarization and extended space of the Dirac hydrogenlike atom. A range of values for the half radius, the surface thickness, and the intrinsic quadrupole moment was obtained. A description of the analysis is included.

NUCLEAR STRUCTURE Energies of $γ$ rays of $K$ and $L$ transitions of muonic ${}^{181}{Ta}$ measured. Data fitted by three parameter modified Fermi distribution of charge.

Antisymmetry in the three-nucleon-interaction matrix elements

M. Waroquier, K. Heyde, and H. Vincx

Phys. Rev. C 13, 1664 (1976) - Published 1 April, 1976

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The inclusion of three-body forces to the effective nucleon-nucleon interaction has been frequently applied in nuclear self-consistent Hartree-Fock calculations. Thus, a dependence of the effective force on the nucleon density is exhibited, stimulating great interest in this manner. Antisymmetrized three-body matrix elements are evaluated, and applied with a zero-range three-body force within a finite basis of spherical single-particle states. The imposed antisymmetry ignores the existence of matrix elements of three identical nucleons. It provides for a better understanding of the structure of the three-body contribution to the Hartree-Fock ground state energy and for the exact relation between the three-body force and a density dependent two-body force. The discussion is given as well for spherical as for deformed nuclei. Problems concerning possible overbinding and violation of the spin stability by the zero-range three-body interaction are examined and represented in the angular momentum picture.

NUCLEAR STRUCTURE antisymmetrized three-body matrix elements; HF ground state energy contribution; equivalence to density dependent two-body forces.

Ground state properties of medium-heavy nuclei with a realistic interaction

A. L. Goodman, J. P. Vary, and R. A. Sorensen

Phys. Rev. C 13, 1674 (1976) - Published 1 April, 1976

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The Brueckner $G$ matrix appropriate for medium-heavy nuclei is obtained from the Reid soft-core nucleon-nucleon potential. The $G$ matrix is strongly affected by the Pauli operator $Q$ , which is treated exactly (no angle averaging). Within the range of valence space energies $G$ has a weak dependence on the starting energy $ω$ . Ground state properties of deformed rare earth nuclei ( $Z = 64 - 76, N = 90 - 102$ ) and spherical semimagic nuclei ( $Sn, Pb, N = 82, N = 126$ ) have been calculated in the Hartree-Fock-Bogoliubov approximation with an inert core of 110 nucleons. Deformations and pair gaps are both determined by the $G$ matrix. The systematic experimental dependence of $ε_{spherical}$ , $β_{2}$ , $β_{4}$ , $Δ_{p}$ , $Δ_{n}$ , and $E_{po}$ (prolate-oblate energy difference) on $N$ and $Z$ is reproduced. However, the magnitudes of $β_{2}$ , $Δ_{n}$ , and $E_{po}$ are too small. This may be largely due to the lack of isospin dependence of the oscillator basis states. $β_{2}$ and $E_{po}$ could receive additional significant contributions from core polarization of the 110 particle core which is neglected here. The Hartree-Fock-Bogoliubov ground states obtained with this realistic interaction provide a reasonable foundation for high spin calculations.

NUCLEAR STRUCTURE Brueckner reaction matrix; Hartree-Fock-Bogoliubov theory; ground state properties of medium-heavy nuclei.

Critique of the locally linearized approximation to the nuclear single particle density matrix

D. Kessler and J. W. Negele

Phys. Rev. C 13, 1698 (1976) - Published 1 April, 1976

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Approximations to the density matrix of a Fermi gas in an external potential by Baltin and by Balazs and Zipfel are shown to be closely related. Predictions for the kinetic energy density using these approximations are compared to exact solutions for two harmonic oscillator problems and for Woods-Saxon wave functions in the lead nucleus. In all three cases, the approximations yield substantial systematic discrepancies, indicating that they are inadequate for quantitative description of the nuclear density matrix.

NUCLEAR STRUCTURE Approximation to single particle density matrix. Corrections to Thomas-Fermi approximation.

Treatment of centrifugal elastic stresses in nuclear rotation

N. Azziz, J. C. Palathingal, and Rubén Méndez-Plácido

Phys. Rev. C 13, 1702 (1976) - Published 1 April, 1976

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A treatment of elastic stresses in nuclear rotation with the nucleus considered as an incompressible elastic body with a stationary spherical core surrounded by a circulating mass is presented. Centrifugal stresses acting in directions perpendicular to the axis of rotation introduce variations in the moment of inertia. The variable moment of inertia model, so successful in predicting the rotational spectrum of even-even nuclei, is explained.

NUCLEAR STRUCTURE Explanation of rotational energy levels for even-even nuclei using elastic stress analysis.

Surface-restricted effective interactions in a shell model application to ${}^{88}{Sr}$

N. Auerbach and J. P. Vary

Phys. Rev. C 13, 1709 (1976) - Published 1 April, 1976

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We compare conventional phenomenological effective interactions acting throughout the nuclear volume with some surface restricted effective interactions for the particle-hole spectrum and properties of ${}^{88}{Sr}$ in a basis of neutron and proton orbitals. The surface restricted forces produce greater configuration mixing and enhance the neutron particle-hole contributions to the lowest-lying states and thus result in better agreement with experiment.

NUCLEAR STRUCTURE ${}^{88}{Sr}$ , Surface or density dependent effective interactions, particle-hole shell model structure, calculated levels, $J$ , $π$ , $B (Λ)$ spectroscopic factors.

Influence of virtual $Δ$ states on the saturation properties of nuclear matter

B. D. Day and F. Coester

Phys. Rev. C 13, 1720 (1976) - Published 1 April, 1976

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The effect of virtual $Δ (1236)$ states on the saturation properties of nuclear matter is studied within the framework of lowest-order Brueckner theory. The $Δ$ is treated as a stable elementary particle. Transitions from the nucleon-nucleon ( $NN$ ) channel to the nucleon- $Δ (N Δ)$ channel are caused by a nonrelativistic potential obtained from the static limit of meson theory. The coupled-channel potentials are constrained to fit the $NN$ phase shifts. Saturation curves are calculated for the couplings ${}^{1}S_{0} (NN) ⇆ {}^{5}D_{0} (N Δ)$ and ${}^{3}P_{1} (NN) ⇆ {}^{5}P_{1} (N Δ)$ , and the effects of other $N Δ$ couplings to nucleon-nucleon $P$ and $D$ waves are estimated. Calculations are done using both the Reid soft-core and Ueda-Green potentials for $NN$ partial waves not coupled to the $N Δ$ channel. The $N Δ$ coupling does not change the usual tendency of the calculated saturation points to lie in a narrow band in the energy-density plane that does not contain the empirical saturation point. This result is illuminated by a rough approximation to the Pauli and dispersion effects. We have also used this approximation to estimate the loss of binding due to $N Δ$ coupling in those channels not treated by detailed calculation. Combining all our results, we find that at the empirical density (1) the inclusion of $N Δ$ coupling in nucleon-nucleon $S$ , $P$ , and $D$ waves reduced the binding energy by about 3.3, 3.2, and 0.8 MeV, respectively, and (2) each particle spends about 3.7% of its time as a $Δ$ . All these figures vary roughly quadratically with the $π N Δ$ coupling constant and increase rapidly with density. The size of the shift in energy depends strongly on the suppression of the short-range part of the two-body wave function, but our approximate formulas indicate that the tendency of the calculated saturation points to remain in a narrow band is independent of the short-range behavior of the two-body interaction, i.e., it is model-independent.

NUCLEAR STRUCTURE Effect of $Δ (1236)$ on saturation of nuclear matter studied in lowest-order Brueckner-Bethe-Goldstone theory.

Self-consistent generator coordinate method

Bernard Laskowski and Erkki Brändas

Phys. Rev. C 13, 1741 (1976) - Published 1 April, 1976

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An optimum continuous representation technique derived in analogy with the self-consistent harmonic approximation in quantum lattice dynamics is discussed and applied to Lipkin's model. The method is based on the variational principle and corresponds to an infinite summation of an expansion of the appropriate Hamiltonian kernel. The overlap kernel is treated exactly. The actual results indicate the removal of the drawbacks of low order perturbation theory previously employed in this connection.

NUCLEAR STRUCTURE Continuous representation method applied to a solvable model.

Upper limit on $Δ T = 2, E 2$ transition in ${}^{44}{Ti}$

W. R. Dixon, R. S. Storey, J. J. Simpson, and R. D. Lawson

Phys. Rev. C 13, 1745 (1976) - Published 1 April, 1976

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An upper limit of 0.16% (one standard deviation) is placed on the $γ$ -ray branching ratio for the $Δ T = 2$ transition from the $T = 2, 0^{+}$ level at 9338 ± 2 keV in ${}^{44}{Ti}$ to the first excited $2^{+}$ level at 1083 keV. A new determination of $\frac{Γ_{α} Γ_{γ}}{Γ}$ for the $T = 2$ level gives 0.24 eV. The upper limit for the $Δ T = 2$ transition is shown to be consistent with shell-model estimates of isospin mixing.

NUCLEAR STRUCTURE $0^{+}$ , $T = 2$ level ${}^{44}{Ti}$ ; measured $γ$ decay, $ω γ$ ; deduced $B (E 2)$ upper limit for $Δ T = 2$ ; calculated $B (E 2)$ .

Alpha- ${}^{40}{Ca}$ optical potentials: Density dependent interactions

I. Brissaud and M. K. Brussel

Phys. Rev. C 13, 1748 (1976) - Published 1 April, 1976

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A linear density dependent effective nucleon-nucleon interaction is used in a folding model to analyze 166 MeV $α$ -particle elastic scattering data from ${}^{40}{Ca}$ . A phenomenological imaginary potential is added to the real potential generated by the model. The density dependence used is insufficient to fit the experimental angular distribution quantitatively. We point out the nature of the change in the optical potential required to achieve better results.

NUCLEAR REACTIONS Optical potentials generated with density-dependent effective nucleon-nucleon interactions applied to 166 MeV $α - {}^{40}{Ca}$ elastic scattering.

Systematics of $N = 45$ nuclei

L. R. Medsker

Phys. Rev. C 13, 1751 (1976) - Published 1 April, 1976

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Double positron-electron pair production by 6.6-MeV gamma rays

Prompt gamma rays from nuclear reactions induced by 380-MeV $π$

Decays of ${}^{88}{Kr}$ and ${}^{88}{Rb}$

Structure of $N = 81$ nuclei: Levels of ${}^{141}{Nd}$ and ${}^{139}{Ce}$ populated in beta decay

On-line mass separator investigation of the new isotope 2.9-sec ${}^{116}I$

Isomerism in the $N = 81$ isotope ${}^{147}{Dy}$

Three-particle one-hole configurations in odd-odd ${}^{134}I$ and the decay of ${}^{134}{Te}$

Gamma-gamma angular correlations in ${}^{105}{Rh}$ following the decay of 4.4-h ${}^{105}{Ru}$

Level schemes of ${}^{91}{Rb}$ and ${}^{91}{Sr}$ populated in beta decay

Distribution of electrical charge in the nucleus of ${}^{181}{Ta}$

Antisymmetry in the three-nucleon-interaction matrix elements

Ground state properties of medium-heavy nuclei with a realistic interaction

Critique of the locally linearized approximation to the nuclear single particle density matrix

Treatment of centrifugal elastic stresses in nuclear rotation

Surface-restricted effective interactions in a shell model application to ${}^{88}{Sr}$

Influence of virtual $Δ$ states on the saturation properties of nuclear matter

Self-consistent generator coordinate method

Upper limit on $Δ T = 2, E 2$ transition in ${}^{44}{Ti}$

Alpha- ${}^{40}{Ca}$ optical potentials: Density dependent interactions

Systematics of $N = 45$ nuclei

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