Recent Articles

Threshold pion photoproduction and radiative pion capture. III. ${}^{3}{He}$ ↔ ${}^{3}H$

W. R. Gibbs, B. F. Gibson, and G. J. Stephenson, Jr.

Phys. Rev. C 18, 1761 (1978) - Published 1 October, 1978

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We have calculated the rate for radiative pion capture from a $1 s$ atomic orbital for the ${}^{3}{He} (π^{-}, γ) {}^{3}H$ analog transition. We obtain reasonable agreement with the experimental Panofsky ratio when this radiative capture rate is combined with our estimate of the corresponding ${}^{3}{He} (π^{-}, π^{0}) {}^{3}H$ charge exchange rate. Threshold pion photoproduction cross section estimates are also given.

NUCLEAR REACTIONS ${}^{3}{He} (π^{-}, γ)$ , ${}^{3}{He} (π^{-}, π^{0})$ ; calculated threshold cross sections, capture rate, Panofsky ratio.

Backward positive pion production from nuclei bombarded with 600 MeV protons, 700 MeV alpha particles, and 350 MeV deuterons

C. F. Perdrisat, S. Frankel, and W. Frati

Phys. Rev. C 18, 1764 (1978) - Published 1 October, 1978

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The momentum dependence, at fixed pion angles of 180 and 155°, of inclusive pion production reactions has been obtained for 600 MeV protons and 175 MeV/nucleon $α$ particles and deuterons on ${}^{6}{Li}$ , C, Co, and Ta. The spectra obtained all fall off exponentially with increasing pion momentum, the slope being about 30 MeV/c independent of either target or projectile nature. The data are examined from the point of view of quasi-two-body scaling, a reaction description discussed recently which suggests that $q_{min}$ , the minimum nuclear recoil momentum possible kinematically, is the proper scaling variable. When plotted versus $q_{min}$ , all data presented here keep their exponential shape, but the slope becomes 70 MeV/c, i.e., nearly the same as obtained for proton production by the same selection of beam projectiles and energies. It is concluded that the same functional of the target momentum space wave function is revealed by quasi-two-body scaling in inclusive pion production experiments, as in inclusive proton and light-fragment production experiments. Finally, the results of a Monte Carlo calculation of pion spectra based on a single $NN \to π NN$ interaction and taking into account the internal motion of the nucleons in target and projectile are presented. The shape and cross sections are accounted for when effective momentum densities of exponential forms are used; the slope constants necessary are compatible with the ones obtained in quasi-two-body scaling. Using the ground state momentum density of an independent particle shell model produces pion spectra which fall off too rapidly. Furthermore, the Monte Carlo calculation reveals kinematical features of the reaction, which help explain why quasi-two-body scaling works for pion production.

NUCLEAR REACTIONS $C (p, π)$ , $E_{p} = 600$ MeV, ( $d, π$ ), $E_{d} = 350$ MeV, ( $α, π$ ) $E_{α} = 700$ MeV; ${}^{6}{Li}$ , Co, and $Ta (d, π)$ , $E_{d} = 350$ MeV, ( $α, π$ ), $E_{α} = 700$ MeV; measured $σ (E_{π}, ⊖_{π})$ at 155 and 180°; magnetic spectrometer; compared with quasi-two-body scaling and Monte Carlo, single interaction calculation; discuss relation to internal motion in target and projectile.

Quasielastic knockout of alpha clusters from light and medium nuclei by 600 MeV protons

G. Landaud, A. Devaux, P. Delpierre, J. Kahane, R. Sené, J. Yonnet, and R. Anne

Phys. Rev. C 18, 1776 (1978) - Published 1 October, 1978

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Knockout of $α$ clusters from light and medium weight nuclei by 600 MeV protons has been investigated. The outgoing protons and $α$ particles were detected in coincidence; their momenta were measured with two large magnetic spectrometers with proportional wire chambers. Experimental methods which were used to work with a high beam rate and an efficient proton rejection in the $α$ arm are described. Separation energy spectra are given for ${}^{6}{Li}$ , ${}^{7}{Li}$ , ${}^{12}C$ , ${}^{24}{Mg}$ , ${}^{27}{Al}$ , and ${}^{40}{Ca}$ nuclei. A peak is observed at an excitation energy equal to zero, except for the ${}^{27}{Al}$ target.

NUCLEAR REACTIONS ${}^{6}{Li}$ , ${}^{7}{Li}$ , ${}^{12}C$ , ${}^{24}{Mg}$ , ${}^{27}{Al}$ , ${}^{40}{Ca} (p, p α)$ , $E_{0} = 600$ MeV; experimental methods; separation energy spectra.

Elastic scattering of deuterons off carbon nuclei

Jayati Ghosh and V. S. Varma

Phys. Rev. C 18, 1781 (1978) - Published 1 October, 1978

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Elastic scattering of deuterons off carbon nuclei is studied in the Glauber model. Fits to the 650 MeV elastic scattering data are attempted using, firstly, nucleon-nucleon data as input and the $α$ -particle model of the carbon nucleus, and, secondly, deuteron-proton scattering data as input with both an independent particle and an $α$ -particle description of the carbon nucleus. In all these cases the best fits are qualitatively the same as those obtained in a recent calculation using nucleon-nucleon data as input with an independent particle model of the nucleus.

NUCLEAR REACTIONS ${}^{12}C (d, d)$ , $E = 650$ MeV; calculation of $σ (E, θ)$ , $σ_{T} (E)$ , and comparison with experiment.

Analytic extensions of Monte Carlo calculations

E. A. Remler

Phys. Rev. C 18, 1786 (1978) - Published 1 October, 1978

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The term quasiclassical is defined to apply to a large class of fundamentally equivalent approximations currently used for reactions involving complex quantum mechanical systems. Their relation to the underlying quantum mechanical problem is clarified. Monte Carlo calculations play a central and paradigmatic role within this class. Analytic formulas for inclusive cross sections involving simple integrals over functions obtained through a Monte Carlo calculation are presented. These are of a completely obvious nature but apparently have not been previously presented. They should greatly increase the convergence rate and range of applicability of Monte Carlo calculations and of quasiclassical calculations is general. The method of derivation allows straightforward generalization to arbitrary final states.

NUCLEAR REACTIONS Quasiclassical stochastic models as quantum mechanical approximations. Monte Carlo trajectories as integration grid maximizes information content utilization. Smooth cross sections also valid for infrequent final states. General perturbation theory.

Gamma-neutrino angular correlation in muon capture by ${}^{28}{Si}$

R. Parthasarathy and V. N. Sridhar

Phys. Rev. C 18, 1796 (1978) - Published 1 October, 1978

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The theory of $γ$ -neutrino angular correlation in nuclear muon capture is developed using the density matrix technique. A closed expression for the correlation coefficient, for unpolarized muon capture and including relativistic terms, is obtained in the particle-hole model for the nucleus. An interesting relation between the correlation coefficient and the longitudinal polarization of the recoil nucleus in muon capture is established. This relation is independent of nuclear models and the muon capture coupling constants, and its importance in connection with time-reversal invariance is pointed out. Utilizing the close analogy between muon capture and inelastic electron scattering, the numerical results for the process $μ^{-} + {}^{28}{Si} (0^{+}) \to {}^{28}{Al}^{*} (1^{+}) + ν_{μ}$ , ${}^{28}{Al}^{*} (1^{+}) \to {}^{28}{Al} (0^{+}) + γ$ are presented. It is found that the correlation coefficient is extremely sensitive to the nuclear model, contrary to common belief, and also sensitive to the induced pseudoscalar coupling constant in muon capture. The results are compared with the available experimental data and a range for $\frac{g_{P}}{g_{A}}$ is obtained as $3 < \frac{g_{P}}{g_{A}} < 20$ , in agreement with other predictions, indicating a remote possibility of the quenching of $g_{P}$ due to virtual pion effects in the $A = 28$ system. With the "canonical" value for $g_{P}$ , our results give $\frac{g_{T}}{g_{A}} = + 4.5 \pm 7.5$ due to the large uncertainty in the experimental data.

NUCLEAR REACTIONS ${}^{28}{Si} (μ^{-}, γ_{ν}) {}^{28}{Al}$ ; $γ$ -neutrino angular correlation coefficient; particle hole model; induced pseudoscalar and tensor form factors.

Levels in ${}^{43}K$ and ${}^{44}K$ excited by the $β$ decay of ${}^{43}{Ar}$ and ${}^{44}{Ar}$

A. Huck, G. Klotz, A. Knipper, C. Miehé, G. Walter, and C. Richard-Serre

Phys. Rev. C 18, 1803 (1978) - Published 1 October, 1978

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The nuclides ${}^{43}{Ar}$ and ${}^{44}{Ar}$ have been produced by spallation reactions on vanadium targets at $E_{p} = 600$ MeV. The subsequent $β$ decays to ${}^{43}K$ and ${}^{44}K$ have been studied via delayed $γ$ -ray singles and $γ - γ$ coincidence techniques. In ${}^{43}K$ , excitation energies and $γ$ -branching fractions have been determined for 19 levels. The $log ft$ values imply $J^{π} = \frac{3}{2^{-}}, \frac{5}{2^{\pm}}$ for the ground state of ${}^{43}{Ar}$ . For ${}^{44}{Ar}$ , evidence is found for four new $β$ branches and $J^{π} = 1^{+}$ is assigned to the levels at 2326 and 2574 keV on the basis of the $β$ decay selection rules. The proposed decay scheme accounts for $γ$ transitions between 10 levels, the first excited state being located at 182.6 keV. The structure of these nuclei is discussed in the weak coupling scheme.

RADIOACTIVITY ${}^{43, 44}{Ar}$ from ${}^{50, 51}V (p, 6 p x n)$ , natural target, mass separated measured delayed $E_{γ}$ , $I_{γ}$ , $γ - γ$ coincidences, deduced decay schemes, $log ft$ , $J$ , $π$ .

Systematic study of the structure of odd-mass lanthanum nuclei. III. Levels in ${}^{133}{La}$ from the decay of 5-h ${}^{133}{Ce}$

E. A. Henry and R. A. Meyer

Phys. Rev. C 18, 1814 (1978) - Published 1 October, 1978

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Levels of ${}^{133}{La}$ populated by the $β$ decay of the $\frac{9}{2^{-}}$ 5-h isomer of ${}^{133}{Ce}$ were studied by $γ$ -ray spectroscopy, $γ - γ$ coincidence counting, and conversion-electron spectroscopy of mass-separated ${}^{133}{Ce}$ sources. The ${}^{133}{La}$ level scheme was greatly extended and substantial differences from previous level schemes were found. Both the observed negative and positive parity levels are accounted for in terms of decoupled band structure by calculations based on thee particle-plus-triaxial-rotor model. Deviations of this simple picture from the experimental data are discussed.

RADIOACTIVITY ${}^{133}{Ce}$ [from $Ba (α, X n)$ ]; measured $E γ$ , $I γ$ , $I_{ce}$ , $γ - γ$ coin; deduced $log ft$ . ${}^{133}{La}$ deduced levels, $J$ , $π$ , ICC. Mass separation, chemical purification from ${}^{133}{La}$ .

$N = 85$ nuclei. II. Decay of 4.15-h ${}^{149}{Tb}^{g}$ to levels of ${}^{149}{Gd}$

S. V. Jackson, J. W. Starner, W. R. Daniels, M. E. Bunker, and R. A. Meyer

Phys. Rev. C 18, 1840 (1978) - Published 1 October, 1978

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The $γ$ -ray spectrum accompanying the decay of 4.15-h ${}^{149}{Tb}^{g}$ has been studied by Ge(Li) singles and coincidence spectroscopy. Sources were prepared via the ${}^{141}\Pr ({}^{12}C, 4 n)$ reaction and via spallation of Ta with 800-MeV protons. Chemical and isotopic separation techniques were employed to obtain pure sources. A total of 325 $γ$ rays are attributed to the decay of ${}^{149}{Tb}^{g}$ , all of which have been placed in a ${}^{149}{Gd}$ level scheme involving 80 excited states. The spin and parity of ${}^{149}{Tb}^{g}$ is postulated to be $\frac{1}{2^{+}}$ . The intensity of the direct $β^{+}$ + electron capture branch from ${}^{149}{Tb}^{g}$ to the ${}^{149}{Gd}$ ground state ( $\frac{7}{2^{-}}$ ) is determined to be (0.5±5.0)%. The intensity of the $α$ -decay branch from ${}^{149}{Tb}^{g}$ to ${}^{145}{Eu}$ has been measured to be (15.8±1.4)%. The observed level structure of ${}^{149}{Gd}$ is discussed in terms of current nuclear models.

RADIOACTIVITY ${}^{149}{Tb}^{g}$ from ${}^{181}{Ta} (p, spall .)$ and from ${}^{141}\Pr ({}^{12}C, 4 n)$ , chemically and isotopically separated sources, measured $E_{γ}$ , $I_{γ}$ , $γ γ$ coin; ${}^{149}{Gd}$ deduced levels, $J$ , $π$ , $log ft$ . Ge(Li) detectors.

Alternative treatment of exchange effects in the theory of radioactive decay

R. Goldflam and W. Tobocman

Phys. Rev. C 18, 1857 (1978) - Published 1 October, 1978

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A derivation of expressions for the decay width for radioactive decay based on many-body scattering theory is presented. The consequences of exchange symmetry are made explicit. Our method differs from an earlier treatment by Tobocman in that is employs a more realistic characterization of the emitted particle and daughter nucleus final state.

RADIOACTIVITY Width for radioactive decay by particle emission derived from many-body scattering theory with special attention to exchange symmetry.

$β - γ$ circular-polarization correlations for first-forbidden $β$ transitions in ${}^{76}{As}$ and ${}^{124}{Sb}$

John R. Pruett and William Sellyey

Phys. Rev. C 18, 1867 (1978) - Published 1 October, 1978

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The $β - γ$ circular-polarization correlations $P_{γ}$ associated with the 1.753 MeV and 2.42 MeV $β$ transitions of ${}^{76}{As}$ and with the 2.31 MeV $β$ transition of ${}^{124}{Sb}$ have been measured as an average over the respective energy intervals $E_{β} = 0.56 to 1.4$ MeV; $E_{β} = 1.4 to 2.1$ MeV, and $E_{β} = 1.66 to 2.31$ MeV. Two $β$ detectors, one at an instrument angle ${θ^{*}}_{1} = 135 °$ and the other at ${θ^{*}}_{2} = 150 °$ , were employed in these measurements. On the assumption that the $A_{3}$ term in $P_{γ}$ is negligible compared to the $A_{1}$ term, the experimental data give the following values for the respective $P_{γ}$ : $P_{γ} ({}^{76}{As} : 0.56 MeV < E_{β} < 1.4 MeV, E_{γ} = 0.559, θ_{β γ} = 180 °) = 0.75 \pm 0.6$ , $P_{γ} ({}^{76}{As} : 1.4 MeV < E_{β} < 2.1 MeV, E_{γ} = 1.216 MeV, θ_{β γ} = 180 °) = 0.11 \pm 0.05$ , $P_{γ} ({}^{124}{Sb} : 1.66 MeV < E_{β} < 2.31 MeV, E_{γ} = 0.603 MeV, θ_{β γ} = 135 °) = 0.47 \pm 0.07$ , and $P_{γ} ({}^{124}{Sb} : 1.66 MeV < E_{β} < 2.31 MeV, E_{γ} = 0.603 MeV, θ_{β γ} = 150 °) = 0.58 \pm 0.08$ .

RADIOACTIVITY ${}^{76}{As}$ ; measured $β γ$ $CP$ , ${}^{124}{Sb}$ ; measured $β γ$ $CP$ .

Half-lives of ${}^{62}{Ga}$ , ${}^{66}{As}$ , and ${}^{70}{Br}$

David E. Alburger

Phys. Rev. C 18, 1875 (1978) - Published 1 October, 1978

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The Fermi superallowed $β^{+}$ activities ${}^{62}{Ga}$ , ${}^{66}{As}$ , and ${}^{70}{Br}$ were produced in the reactions ${}^{58}{Ni} ({}^{6}{Li}, 2 n) {}^{62}{Ga}$ at $E_{{}^{6}{Li}} = 25$ MeV ${}^{58}{Ni} ({}^{10}B, 2 n) {}^{66}{As}$ at $E_{{}^{10}B} = 30$ MeV, and ${}^{58}{Ni} ({}^{14}N, 2 n) {}^{70}{Br}$ at $E_{{}^{14}N} = 44$ MeV. Half-lives were determined by multi-scaling pulses from a plastic $β$ ray detector. The measured half-lives are as follows: ${}^{62}{Ga}$ —115.95±0.30 ms, ${}^{66}{As}$ —95.78 ±0.39 ms, and ${}^{70}{Br}$ —80.2±0.8 ms. An attempt to observe the decay of ${}^{74}{Rb}$ , produced in the ${}^{58}{Ni} ({}^{19}F, 3 n) {}^{74}{Rb}$ reaction at $E_{{}^{19}F} = 60 - 68$ MeV, was unsuccessful.

RADIOACTIVITY ${}^{62}{Ga}$ , ${}^{66}{As}$ , ${}^{70}{Br}$ ; measured $T_{\frac{1}{2}}$ .

Electromagnetic transitions between the low-lying levels of ${}^{21}{Ne}$ and their relation to parity mixing of the 2.80-MeV $\frac{1}{2^{\pm}}$ doublet

D. J. Millener, E. K. Warburton, K. A. Snover, R. von Lintig, and P. G. Ikossi

Phys. Rev. C 18, 1878 (1978) - Published 1 October, 1978

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The presence of a $J^{π} = \frac{1}{2^{+}} - \frac{1}{2^{-}}$ doublet ( $Δ E ≃ 8$ keV) at 2.80 MeV in ${}^{21}{Ne}$ provides an opportunity to further investigate parity mixing of nuclear states. The parity mixing in ${}^{21}{Ne}$ introduces an irregular $M 1$ , $E 2$ admixture into the regular, but highly retarded, $E 1$ , $M 2$ decay of the $\frac{1}{2^{-}}$ level to the $\frac{3}{2^{+}}$ ground state and can be inferred from the interference between these irregular and regular decays. We consider the dependence of possible ${}^{21}{Ne}$ parity-mixing observables on the four electromagnetic matrix elements involved in the transition and also methods for determining these matrix elements. The first step towards a measurement of the $\frac{M 2}{E 1}$ mixing ratio is a measurement of the $\frac{E 3}{M 2}$ mixing ratio of the $\frac{1}{2^{-}} \to \frac{5}{2^{+}}$ transition in ${}^{21}{Ne}$ and this is carried out using a $γ - γ$ correlation utilizing the ${}^{18}O (α, n)$ ${}^{21}{Ne}$ reaction. A large basis SU(3) shell-model calculation is performed to give wave functions for ${}^{21}{Ne}$ (and ${}^{21}{Na}$ ) and predictions for the electromagnetic matrix elements relevant to studies of the $\frac{1}{2^{\pm}}$ parity mixing. The parity-mixing matrix element is calculated using a one-body approximation to the parity nonconserving interaction. The calculated matrix elements are compared with the available experimental data on ${}^{21}{Ne}$ and ${}^{21}{Na}$ .

NUCLEAR STRUCTURE ${}^{21}{Ne}$ , ${}^{21}{Na}$ ; calculated nuclear wave functions, electromagnetic, parity-mixing matrix elements. SU(3) shell-model method. ${}^{21}{Ne}$ ; measured $γ - γ$ ${\frac{1}{2}}^{-} \to {\frac{5}{2}}^{+} \to {\frac{3}{2}}^{+}$ angular correlation. Deduced ${\frac{1}{2}}^{-} \to {\frac{5}{2}}^{+}$ $\frac{E 3}{M 2}$ mixing ratio. ${}^{21}{Ne}$ ; calculated $γ$ -ray CP and asymmetry formulas for polarized and unpolarized beams.

Adiabaticity of time-dependent Hartree-Fock solutions

P. Bonche and P. Quentin

Phys. Rev. C 18, 1891 (1978) - Published 1 October, 1978

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A tractable method is presented for the study of the adiabaticity of a given time-dependent Hartree-Fock solution. In terms of the Baranger-Vénéroni approach, this amounts to extracting the two operators $ρ_{0}$ and $χ$ , for which rather simple expressions are derived. These explicit formulas are exploited to illustrate some implications of the adiabatic approximation itself and several related approximations. In particular, the incompatibility of two current hypotheses for the $χ$ operator (locality and absence of particle-particle, hole-hole matrix elements) is pointed out. Finally, the whole discussion is exemplified by the simple case of uniform translational motion.

NUCLEAR STRUCTURE Discussion of adiabatic limit of TDHF approximation, derivation of practical method of study adiabaticity of collective motion from TDHF solutions.

Exponential model with pairing attenuation and the backbending phenomenon

P. C. Sood and A. K. Jain

Phys. Rev. C 18, 1906 (1978) - Published 1 October, 1978

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Rotational energy calculations with an exponential dependence of the nuclear moment of inertia on pairing correlations coupled with an explicit spin dependence of the effective pairing gap analogous to that used in superconductivity give an excellent fit to the experimental data on excitation energies of yrast band levels in well-deformed even-even nuclei and also reproduce the backbending feature satisfactorily. The variation of the pairing gap parameter with spin is found to be gradual and smooth as compared to the abrupt variation evidenced in the pairing collapse treatment. Variations of the limiting moments of inertia parameter with mass number derived from our model exactly match with those coming out of the cranking model calculations for neutrons and are in no way related to the proton results for lighter rare earth nuclei; also the fluctuations in the values of the moment of inertia are found to correspond to those of the neutron single particle level spacings in this region.

NUCLEAR STRUCTURE Even-even well-deformed rare earth nuclei, calculated yrast band level energies, exponential dependence of moment of inertia on pairing, explicit variation of pairing with spin, compared with experimental data and other calculations.

Comments on off-energy-shell generalization of the Jost-Pais theorem

B. Talukdar, U. Das, and D. Chattarji

Phys. Rev. C 18, 1917 (1978) - Published 1 October, 1978

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It is shown that an off-shell generalization of the Jost-Pais theorem given by Warke and Srivastava does not yield the correct outgoing wave (physical) scattering solution.

NUCLEAR REACTIONS Scattering theory, incompatibility of off-energy-shell generalization of the Jost-Pais theorem and off-shell physical wave function.

Reply to "Comments on off-energy-shell generalization of the Jost-Pais theorem"

C. S. Warke and M. K. Srivastava

Phys. Rev. C 18, 1919 (1978) - Published 1 October, 1978

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Two-nucleon transfer to $T$ -mixed states in ${}^{16}O$

H. T. Fortune, R. Middleton, and O. M. Bilaniuk

Phys. Rev. C 18, 1920 (1978) - Published 1 October, 1978

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In a comparison of the reactions ${}^{14}N (t, p)$ to the g.s. quadruplet of ${}^{16}N$ and ${}^{14}N ({}^{3}{He}, p)$ to the dominantly $T = 1$ analogs in ${}^{16}O$ , only the $2^{-}$ levels have the expected cross-section ratio: $\frac{σ ({}^{3}{He}, p)}{σ (t, p)} = 0.5$ . The cross sections for $O^{-}$ and $3^{-}$ levels of ${}^{16}O$ are reduced by a further factor of 2. Direct-reaction calculations are unable to reproduce the results.

NUCLEAR REACTIONS ${}^{14}N (t, p)$ , ${}^{14}N ({}^{3}{He}, p)$ , $E = 15.0$ MeV; measured $σ (E_{p}, θ)$ . $T$ mixing effect on reaction mechanism.

Effective interactions in $sd$ shell

K. P. Joshi, S. C. Gupta, S. Bennikutty, and A. N. Mishra

Phys. Rev. C 18, 1924 (1978) - Published 1 October, 1978

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The interaction of Preedom and Wildenthal is examined in terms of the spin tensor components in the various relative states. For comparison the bare and the renormalized interactions of Kuo are also studied. The Preedom-Widenthal interaction has a few interaction components much different from the other two interactions examined and from other interactions.

NUCLEAR STRUCTURE Nature of effective interaction, spin tensor components, radial integrals.

RAPID COMMUNICATION

Elastic excitation function of ${}^{12}C$ on ${}^{40}{Ca}$ at 180°

T. R. Renner, J. P. Schiffer, D. Horn, G. C. Ball, and W. G. Davies

Phys. Rev. C 18, 1927(R) (1978) - Published 1 October, 1978

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An excitation function of elastically scattered ${}^{12}C$ from ${}^{40}{Ca}$ at $θ_{c . m .} = 180 °$ was measured at 10 center-of-mass energies between 30.0 and 34.2 MeV to observe whether the anomalous structure that was seen in the back-angle excitation function of ${}^{12}C$ and ${}^{16}O$ on ${}^{28}{Si}$ also existed in this system. The cross section is ∼ $10^{- 4}$ times that for Rutherford scattering, which is about two orders of magnitude lower than was seen with ${}^{28}{Si}$ . A resonance-like energy dependence was observed.

NUCLEAR REACTIONS ${}^{40}{Ca}$ ( ${}^{12}C$ , ${}^{12}C$ ); $σ (E)$ measured at $θ = 180 °$ , $E = 135 - 150$ MeV.

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Recent Articles

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Recent Issues

Threshold pion photoproduction and radiative pion capture. III. ${}^{3}{He}$ ↔ ${}^{3}H$

Backward positive pion production from nuclei bombarded with 600 MeV protons, 700 MeV alpha particles, and 350 MeV deuterons

Quasielastic knockout of alpha clusters from light and medium nuclei by 600 MeV protons

Elastic scattering of deuterons off carbon nuclei

Analytic extensions of Monte Carlo calculations

Gamma-neutrino angular correlation in muon capture by ${}^{28}{Si}$

Levels in ${}^{43}K$ and ${}^{44}K$ excited by the $β$ decay of ${}^{43}{Ar}$ and ${}^{44}{Ar}$

Systematic study of the structure of odd-mass lanthanum nuclei. III. Levels in ${}^{133}{La}$ from the decay of 5-h ${}^{133}{Ce}$

$N = 85$ nuclei. II. Decay of 4.15-h ${}^{149}{Tb}^{g}$ to levels of ${}^{149}{Gd}$

Alternative treatment of exchange effects in the theory of radioactive decay

$β - γ$ circular-polarization correlations for first-forbidden $β$ transitions in ${}^{76}{As}$ and ${}^{124}{Sb}$

Half-lives of ${}^{62}{Ga}$ , ${}^{66}{As}$ , and ${}^{70}{Br}$

Electromagnetic transitions between the low-lying levels of ${}^{21}{Ne}$ and their relation to parity mixing of the 2.80-MeV $\frac{1}{2^{\pm}}$ doublet

Adiabaticity of time-dependent Hartree-Fock solutions

Exponential model with pairing attenuation and the backbending phenomenon

Comments on off-energy-shell generalization of the Jost-Pais theorem

Reply to "Comments on off-energy-shell generalization of the Jost-Pais theorem"

Two-nucleon transfer to $T$ -mixed states in ${}^{16}O$

Effective interactions in $sd$ shell

Elastic excitation function of ${}^{12}C$ on ${}^{40}{Ca}$ at 180°

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