Recent Articles

Analysis of four-body final states: Nonrelativistic

Sadhan K. Adhikari and R. D. Amado

Phys. Rev. C 15, 498 (1977) - Published 1 February, 1977

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The constraints of unitarity and analyticity on four-body final state amplitudes are studied. It is shown that unitarity alone forces the amplitudes to be coherent and have rapid (singular) behavior. The implementation of unitarity yields a set of linear integral equations for the four-body amplitudes that are the minimal set consistent with quantum mechanics, but are also equivalent to the full dynamical equation with separable interactions.

NUCLEAR REACTIONS Four-body final state interaction theory; development and implementation of unitarity and analyticity constraints.

${}^{37}{Cl} ({}^{3}{He}, p) {}^{39}{Ar}$ reaction

William C. Corwin and Ralph E. Segel

Phys. Rev. C 15, 505 (1977) - Published 1 February, 1977

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Proton spectra from the ${}^{37}{Cl} ({}^{3}{He}, p) {}^{39}{Ar}$ reaction were taken at bombarding energies of 17 and 19 MeV at angles between 5° and 40°. A total of 28 states were observed below 5 MeV, most of which can be identified with states reported in other reactions. Between 5 and 7 MeV, 19 more peaks were seen and it is probable that many of these do not correspond to a single level. Dominating the spectrum is the transition to the 9.078 MeV level, which is the analog of the ${}^{39}{Cl}$ ground state. The antianalog of the 9.078 MeV level is predicted to lie at about 2.4 MeV and, in the simplest shell model picture, should be strongly fed. However, no such transition was found. Evidence is presented that suggests that the 3.383 MeV state, which is fed much more weakly than the analog, contains much of the antianalog configuration with some fragmentation to higher energies indicated. This state appears to belong to the class of multiparticle, multihole states of unstretched isospin that lie at a higher than expected energy, but the reason for the existence of this class remains unclear. The analog and several other states, including the suspected antianalog, exhibit an $L = 0$ angular distribution. Distorted-wave Born approximation calculations give a fair fit to both the ground and the first excited state transitions when wave functions from a shell model calculation are used.

NUCLEAR REACTIONS ${}^{37}{Cl} ({}^{3}{He}, p)$ , $E_{3_{He}} = 17 and 19$ MeV. Measured $σ (E_{p}, θ)$ , $5 ° \leq θ \leq 40 °$ , DWBA two-particle transfer analysis. Antianalog search.

Analyzing power for ${}^{4}{He} (p, p) {}^{4}{He}$ scattering at 11.93 and 17.00 MeV

R. A. Hardekopf and G. G. Ohlsen

Phys. Rev. C 15, 514 (1977) - Published 1 February, 1977

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An angular distribution of the analyzing power for ${}^{4}{He} (p, p) {}^{4}{He}$ elastic scattering was measured at 17.00 MeV to an absolute precision of ±0.01. The normalization uncertainty was verified by measurements at 11.93 MeV, 112° (lab), where $A_{y}$ is known to reach 1.0. The data are presented in tabular and graphical form along with predictions from published phase shifts.

NUCLEAR REACTIONS ${}^{4}{He} (p, p) {}^{4}{He}$ , $E_{p} = 11.93 and 17.00$ MeV; measured analyzing power $A_{y} (θ)$ at $θ_{c . m .} = 119 ° - 134 °$ and $θ_{c . m .} = 37 - 157 °$ respectively.

Elastic scattering of protons by helium 4: New experiments and analysis

D. C. Dodder, G. M. Hale, Nelson Jarmie, J. H. Jett, P. W. Keaton, Jr., R. A. Nisley, and K. Witte

Phys. Rev. C 15, 518 (1977) - Published 1 February, 1977

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Accurate measurements of $p - α$ elastic scattering cross sections were made at energies of 11.157, 12.040, 13.600, and 14.230 MeV. The average relative error is about 0.6% and the scale error is 0.37%. These data and all available cross section and spin-dependent measurements of $p - α$ scattering between 0 and 18 MeV were collected and prepared for input to a general purpose $R$ -matrix analysis program. Strict statistical criteria were used for the elimination of data. The resulting search on 1131 data produced a unique fit with a $χ^{2}$ per degree of freedom of 1.001 which is within one standard deviation in $χ^{2}$ space. Arbitrary normalizations to the data were not allowed; a normalization was treated as another datum restrained by a scale error obtained from the experimental information. The parameter space was made up of background contributions in $S$ , $P$ , $D$ , and $F$ states with an additional level each in the $P_{\frac{3}{2}}$ and $P_{\frac{1}{2}}$ states. There were 14 free parameters. For the first time, the reduced widths of the $p$ -wave resonance states come out almost equal. Comparisons are made to the $R$ -matrix analysis of Stammbach and Walter and to the phase shift analysis of Arndt, Roper, and Shotwell.

NUCLEAR REACTIONS ${}^{4}{He} (p, p)$ , $E = 11 - 14$ MeV; measured $σ (θ)$ , $θ (c . m .) = 19 - 167 °$ , $Δ θ = 0.03 °$ , $Δ σ = 0.06 %$ ; calculated $R$ -matrix parameters for all ${}^{4}{He} (p, p) {}^{4}{He}$ data, $E = 0 - 17$ MeV.

Correlations and dipole excitations in nuclei

A. Z. Mekjian and W. M. MacDonald

Phys. Rev. C 15, 531 (1977) - Published 1 February, 1977

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A microscopic calculation of the effect of two-body correlations on the distribution of dipole strength in nuclei is presented. Large corrections are found for the bremsstrahlung-weighted cross section. An isospin decomposition of the cross section is made and the effect of correlations on the isoscalar, isovector, and isotensor parts is studied. Large corrections to the isotensor part, initially small in the oscillator model, are confirmed. The effects on the photoabsorption cross section of coupling the ground state to the giant isovector monopole vibration are also investigated. This component describes the relative distortion of corresponding neutron and proton wave functions and is shown to be included in an analog spin function. The dominant effect on ground state expectation values of this distortion is shown to be the result of dynamic distortion rather than isospin impurity.

NUCLEAR REACTIONS Effect of dynamical correlations on isospin projected sum rules for dipole absorption.

${}^{3}{He} (γ, 2 p) n$ reaction

B. F. Gibson and D. R. Lehman

Phys. Rev. C 15, 545 (1977) - Published 1 February, 1977

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Cross sections for the ${}^{3}{He} (γ, 2 p) n$ coincidence reaction are calculated in the energy range $15 \leq E_{γ} \leq 50$ MeV for the coplanar geometry. The calculation is performed within the context of exact three-body theory where the two-nucleon interactions are represented by $s$ -wave spin-dependent separable potentials fitted to low-energy nucleon-nucleon scattering data. The Coulomb force between the protons is neglected. The cross section is found to be most sensitive to the parametrization of the singlet interaction in the final state when two nucleons exit in close proximity.

NUCLEAR REACTIONS Photodisintegration of ${}^{3}{He}$ ; exact three-body calculation; separable potentials; coincidence cross sections.

8.92 MeV doublet and 8.98 MeV level in ${}^{15}O$

D. Drain, B. Chambon, M. Lambert, C. Pastor, N. Persehaye, J. L. Vidal, and P. Midy

Phys. Rev. C 15, 551 (1977) - Published 1 February, 1977

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The analysis of excitation curves and angular correlations of the $γ$ rays from the ${}^{14}N (p, γ) {}^{15}O$ reaction confirms the existence of a doublet at 8.92 MeV in ${}^{15}O$ . $J^{π} = {\frac{1}{2}}^{+}$ and $J^{π} = {\frac{1}{2}}^{-}$ assignments are determined for the spins and parities of the two members of this doublet. The 8.98 MeV level is found to have $J^{π} = {\frac{3}{2}}^{-}$ . This study was performed using a differentially pumped gas target of natural nitrogen. A comparison with ${}^{15}N$ levels and with theoretical results is discussed.

NUCLEAR REACTIONS ${}^{14}N (p, γ)$ , $E = 1.742, 1806$ MeV. Measured $σ (E)$ , $γ γ (θ)$ . ${}^{15}O$ levels deduced $J$ , $π$ . Natural gas target.

Off-energy-shell generalization of the results in potential scattering

C. S. Warke and M. K. Srivastava

Phys. Rev. C 15, 561 (1977) - Published 1 February, 1977

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Within the framework of nonrelativistic potential scattering theory, an off-energy-shell generalization of the various solutions and the potential matrix elements is carried out. Some relations between these solutions and between the matrix elements are derived. The off-energy-shell generalization of the Jost-Pais theorem is proved for a general nonlocal interaction. A constraint on the $t$ matrix elements of a local potential is obtained. For given $t$ matrix elements, the value of a certain expression gives a measure of the nonlocality of the underlying interaction.

NUCLEAR REACTIONS Off-energy-shell potential scattering theory, relations between the solutions and between the potential matrix elements. Off-energy-shell Jost-Pais theorem. Constraint on $t$ matrix.

Observation of a narrow state at 10.459 MeV in ${}^{15}O$ via the ${}^{14}N (p, γ) {}^{15}O$ reaction

H. M. Kuan, D. G. Shirk, and S. Fiarman

Phys. Rev. C 15, 569 (1977) - Published 1 February, 1977

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A previously unobserved narrow resonance was found in the ${}^{14}N (p, γ) {}^{15}O$ reaction at $E_{p} = 3.392 \pm 0.005$ MeV ( $E_{x} = 10.459 \pm 0.005$ MeV) with $Γ < 2$ keV, $ω γ = 29 \pm 10$ meV, and $γ$ decay branchings 62% to the 5.24- and 38% to the 7.28-MeV final states. The ${}^{15}O$ state corresponding to this resonance is identified as the 10.45-MeV, $J \geq \frac{9}{2}$ state observed in ${}^{12}C ({}^{6}{Li}, t)$ which is presumed to be the analog of the $\frac{9}{2^{+}}$ state at 10.693 MeV in ${}^{15}N$ . The decay of the ${}^{15}O$ 10.47-MeV level is also measured.

NUCLEAR REACTIONS ${}^{14}N (p, γ)$ , $E_{p} = 3.15 - 3.5$ MeV, measured $σ (E, θ)$ , deduced $E$ , $Γ$ , $ω γ$ , and branching ratios of the ${}^{15}O$ states at 10.459 and 10.47 MeV.

Empirical evidence for the importance of coherence effects in the ${}^{34}S (p, α) {}^{31}P$ reaction

F. Pellegrini, G. Calvelli, P. Guazzoni, and S. Micheletti

Phys. Rev. C 15, 573 (1977) - Published 1 February, 1977

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Differential cross sections have been measured for the ${}^{34}S (p, α) {}^{31}P$ reaction at an incident energy of 35.5 MeV. The ( $p, α$ ) relative strengths obtained by distorted wave analyses with a triton cluster form factor are well reproduced by current shell model wave functions. The large differences observed between the ${}^{34}S (p, α) {}^{31}P$ and ${}^{32}S (d, {}^{3}{He}) {}^{31}P$ strengths are due to coherence effects which play an important role in the ( $p, α$ ) reaction amplitude.

NUCLEAR REACTIONS ${}^{34}S (p, α) {}^{31}P$ , $E = 35.5$ MeV; measured $σ (E, θ)$ ; enriched target. DWBA analysis.

Absolute resonance strengths in the ${}^{20, 21, 22}{Ne} (p, γ) {}^{21, 22, 23}{Na}$ and ${}^{21}{Ne} (p, p_{1} γ) {}^{21}{Ne}$ reactions

J. Keinonen, M. Riihonen, and A. Anttila

Phys. Rev. C 15, 579 (1977) - Published 1 February, 1977

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The ${}^{21}{Ne} (p, γ) {}^{22}{Ne}$ and ${}^{21}{Ne} (p, p_{1} γ) {}^{21}{Ne}$ reactions have been studied in the energy range $E_{p} = 0.5 - 2.0$ MeV. The absolute resonance strengths $S = 13 \pm 2$ eV and 0.20 ± 0.03 keV have been obtained for the first time in the ${}^{21}{Ne} (p, γ) {}^{22}{Na}$ and ${}^{21}{Ne} (p, p_{1} γ) {}^{21}{Ne}$ reactions at $E_{p} = 1205 and 1090$ keV, respectively. The absolute resonance strengths of 25 ( $p, γ$ ) and 27 ( $p, p_{1} γ$ ) resonances in ${}^{22}{Na}$ have been determined relative to these values. The strengths $S = 1.6 \pm 0.3 and 21 \pm 2$ eV for the ( $p, γ$ ) resonances at $E_{p} = 1169 and 1278$ keV in ${}^{21}{Na}$ and ${}^{23}{Na}$ , respectively, have been remeasured. The total widths have been determined for 24 resonances in ${}^{22}{Na}$ using a thin ${}^{21}{Ne}$ target. The $γ$ -ray decay properties of resonances in ${}^{22}{Na}$ and the astrophysical importance of the $p, γ$ resonance strengths in ${}^{21, 22, 23}{Na}$ are discussed.

NUCLEAR REACTIONS ${}^{21}{Ne} (p, γ)$ ,( $p, p_{1} γ$ ), $E = 0.5 - 2.0$ MeV, ${}^{20}{Ne} (p, γ)$ , $E = 1.2$ MeV, ${}^{22}{Ne} (p, γ)$ $E = 1.3$ MeV; measured $σ (E)$ ; deduced resonance strengths. Enriched targets.

${}^{140}{Ce} (d, p) {}^{141}{Ce}$ at 17 MeV

J. E. Park, W. W. Daehnick, and M. J. Spisak

Phys. Rev. C 15, 587 (1977) - Published 1 February, 1977

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The reaction ${}^{140}{Ce} (d, p)$ has been studied at an incident deuteron energy of 17 MeV. Reaction protons were detected with an Enge split-pole spectrograph using a high-resolution position-sensitive (helix) gas counter and photographic emulsions as detectors. The energy resolution ranged from 11 to 13 keV. Angular distributions were measured in 3-5° steps for $6 ° \leq θ \leq 55 °$ . $l$ -transfer assignments and spectroscopic factors have been deduced for 46 levels up to an excitation energy of 3.7 MeV in ${}^{141}{Ce}$ by comparison with zero-range distorted-wave Born approximation calculations. We note that in spite of the neutron shell closure at $N = 82$ , no ${}^{141}{Ce}$ state has a spectroscopic factor in excess of 0.80. All neutron states are fragmented and considerable spectroscopic strength for $l = 1 and 3$ is spread up to and above 3 MeV. Two well resolved fragments each for the $h_{\frac{9}{2}}$ and $i_{\frac{13}{2}}$ states very nearly fill the sum rules for these single-particle states. The structure of ${}^{141}{Ce}$ levels below 2 MeV is well reproduced by the unified model calculations of Heyde, Waroquier, and Vincx.

NUCLEAR REACTIONS ${}^{140}{Ce} (d, p)$ , $E_{d} = 17$ MeV; measured $σ (E_{p}, θ)$ , resolution 11 keV. DWBA analysis, deduced $l$ , $π$ , $J$ , spectroscopic factors.

Direct population of $j_{p} + j_{n} = J_{max}$ two-particle states in ${}^{206, 208, 210}{Bi}$

W. W. Daehnick, M. J. Spisak, R. M. DelVecchio, and W. Oelert

Phys. Rev. C 15, 594 (1977) - Published 1 February, 1977

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Closely related high spin states in ${}^{206}{Bi}$ , ${}^{208}{Bi}$ , and ${}^{210}{Bi}$ are preferentially excited in the ${}^{204, 206, 208}{Pb} (α, d)$ reaction at 48 MeV. The character of these states can be understood from the selectivity of the ( $α, d$ ) transfer mechanism and experimental systematics. Microscopic distorted-wave Born approximation predictions are consistent with new $J^{π}$ assignments for 14 strongly excited states with $9 \leq J \leq 14$ . The accuracy of standard distored-wave Born approximation predictions for $Pb (α, d)$ at 48 MeV changes systematically with increasing $L$ transfer from good ( $L \leq 5$ ) to poor ( $L \geq 11$ ). This shortcoming is not overcome by full finite range calculations. The strong population of $10^{-}$ , $11^{+}$ , $12^{+}$ , and $14^{-}$ states involves the largest $L$ transfers in direct reactions observed to date.

NUCLEAR REACTIONS ${}^{204, 206, 208}{Pb} (α, d)$ , $E_{α} = 48$ MeV, measured $σ (E_{d}, θ)$ , resolution 25 keV. DWBA analysis, deduced $l$ , $π$ , $J$ of $J_{max}$ states.

Neutron total cross sections and resonance parameters of ${}_{29}^{63}{Cu}$ and ${}_{29}^{65}{Cu}$ . I

M. S. Pandey, J. B. Garg, and J. A. Harvey

Phys. Rev. C 15, 600 (1977) - Published 1 February, 1977

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High resolution neutron total cross sections of the isotopes of copper have been measured from about 10 to 150 keV using 5 nsec electron pulses and a flight path of 78.2 m. From the area and shape analysis of the transmission and total cross section data, precise values of the resonance parameters, such as $E_{0}$ , $Γ_{n}^{0}$ , $Γ_{n}^{1}$ , $J^{π}$ , etc., have been determined. For example, for ${}^{63}{Cu}$ many $s$ -wave resonances have been observed from 10 to 150 keV giving values of ${〈 D 〉}_{J = 1} = (2.7 \pm 0.3)$ keV, ${〈 D 〉}_{J = 2} = (4.0 \pm 0.5)$ keV, ${〈 D 〉}_{J = 1 + 2} = (1.63 \pm 0.13)$ keV, $S_{0 J = 1} = (3.0 \pm 0.6) \times 10^{- 4}$ e $V^{- ½}$ , $S_{0 J = 2} = (2.0 \pm 0.5) \times 10^{- 4}$ e $V^{- ½}$ , $S_{0 J = 1, 2} = (2.5 \pm 0.4) \times 10^{- 4}$ e $V^{- ½}$ . For ${}^{65}{Cu}$ $s$ -wave resonances were observed giving values of ${〈 D 〉}_{J = 1} = (3.6 \pm 0.4)$ keV, ${〈 D 〉}_{J = 2} = (5.0 \pm 0.7)$ keV, ${〈 D 〉}_{J = 1 + 2} = (2.12 \pm 0.19)$ keV, $S_{0 J = 1} = (2.9 \pm 0.6) \times 10^{- 4}$ e $V^{- ½}$ , $S_{0 J = 2} = (1.8 \pm 0.5) \times 10^{- 4}$ e $V^{- ½}$ , $S_{0 J = 1, 2} = (2.3 \pm 0.4) \times 10^{- 4}$ e $V^{- ½}$ .

NUCLEAR REACTIONS ${}^{63, 65}{Cu} (n, n)$ , deduced $E_{0}$ , $Γ_{n}$ , $S_{0}$ , $〈 D 〉$ , etc., and investigated the distribution about their average values.

High-resolution neutron capture cross sections in ${}^{63}{Cu}$ and ${}^{65}{Cu}$ . II

M. S. Pandey, J. B. Garg, R. Macklin, and J. Halperin

Phys. Rev. C 15, 615 (1977) - Published 1 February, 1977

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Neutron capture cross sections in separated isotopes of copper ( ${}^{63}{Cu}$ and ${}^{65}{Cu}$ ) from a few keV to a few hundreds of keV were measured. From these measurements the capture yields of resonances were accurately determined, giving precise values of $g Γ_{n}$ and $Γ_{γ}$ up to a maximum neutron energy of 50 keV. For ${}^{63}{Cu}$ one obtains a value of $〈 Γ_{γ} 〉 = 490 \pm 30$ meV, $p$ -wave average level spacing ${〈 D 〉}_{l = 1} = 0.495 \pm 0.026$ keV, and strength function $S_{1} = (0.44 \pm 0.07) \times 10^{- 4}$ e $V^{- ½}$ . For ${}^{65}{Cu}$ , one obtains a value for $〈 Γ_{γ} 〉 = 385 \pm 20$ meV, ${〈 D 〉}_{l = 1} = 0.685 \pm 0.060$ keV, and $S_{1} = (0.47 \pm 0.08) \times 10^{- 4}$ e $V^{- ½}$ . The corresponding $s$ -wave mean level spacings for ${}^{63}{Cu}$ and ${}^{65}{Cu}$ are 1.04±0.11 and 1.47±0.19 keV, respectively. Some few of the narrowest levels have been assumed formed by $d$ waves.

NUCLEAR REACTIONS ${}^{63, 65}{Cu} (n, γ)$ ; deduced $E_{0}$ , $g Γ_{n}$ , $Γ_{γ}$ , $S_{1}$ , $S_{2}$ , and their distribution about average values.

$3^{-}$ octupole states in the even Cd nuclei

T. M. Newton, J. M. Davidson, H. R. Hooper, P. W. Green, D. M. Sheppard, and G. C. Neilson

Phys. Rev. C 15, 630 (1977) - Published 1 February, 1977

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Gamma-ray angular distributions from the decay of states at 1959 keV excitation in ${}^{114}{Cd}$ and 1923 keV and 1930 keV excitation in ${}^{116}{Cd}$ are shown to be consistent with assignments of $3^{-}$ for these levels.

NUCLEAR REACTIONS ${}^{114, 116}{Cd} (n, n^{'} γ)$ , $E \leq 2.67$ MeV; measured $σ (E_{γ}, θ_{γ})$ ; ${}^{114, 116}{Cd}$ deduced $J$ , $π$ , $δ$ . Enriched targets. Ge(Li) detectors.

Intermediate coupling in ${}^{203, 205}{Tl}$

J. M. Davidson, I. W. Green, H. R. Hooper, D. M. Sheppard, and G. C. Neilson

Phys. Rev. C 15, 635 (1977) - Published 1 February, 1977

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The excited states of ${}^{203, 205}{Tl}$ were studied using the ${}^{203, 205}{Tl} (n, n^{'} γ)$ reactions. $γ$ -ray angular distributions were measured and spin assignments were made for excited states in both nuclei. An intermediate coupling model calculation was performed in which these nuclei were represented by the coupling of a single hole in the $3 s_{\frac{1}{2}}$ , $2 d_{\frac{3}{2}}$ , $2 d_{\frac{5}{2}}$ , and $1 g_{\frac{7}{2}}$ proton shells to the quadrupole vibrations of the appropriate Pb core. The results of these calculations were compared with the experimental results of this and previous works.

NUCLEAR REACTIONS ${}^{203, 205}{Tl} (n, n^{'} γ)$ , $E = 1.03 - 2.26$ MeV; measured $E_{γ}$ , $σ (E_{γ}, θ_{γ})$ ; ${}^{203, 205}{Tl}$ deduced levels, $J$ , $π$ , $δ$ . Intermediate coupling model calculation. Enriched and natural targets. Ge(Li) detectors.

Levels in ${}^{97}{Ru}$ from ${}^{96}{Ru} (d, p)$

L. R. Medsker, L. H. Fry, Jr., and J. L. Yntema

Phys. Rev. C 15, 649 (1977) - Published 1 February, 1977

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The ${}^{96}{Ru} (d, p) {}^{97}{Ru}$ reaction was studied with 16-MeV deuterons, and the experimental angular distributions were analyzed to determine $l$ values and spectroscopic strengths. Combined with previous information from radioactive decay work, the present data allow new assignments for the $J^{π}$ of levels in ${}^{97}{Ru}$ and the parities of ${}^{97}{Rh}^{g, m}$ . The results are also compared with previous ( $d, p$ ) data on the other $N = 52$ isotones. The measured ${}^{96}{Ru} (d, p)$ $Q$ value leads to a more accurate value for the ${}^{97}{Ru}$ mass excess, -86 118±9 keV.

NUCLEAR REACTIONS ${}^{96}{Ru} (d, p)$ , $E = 16$ MeV; measured $σ (E_{p}, θ)$ ; ${}^{97}{Ru}$ deduced levels, $l_{n}$ , $G_{lj}$ , mass excess.

Mass systematics of evaporation residues from ${}^{35}{Cl}$ - and ${}^{32}S$ -induced fusion on light targets

T. M. Cormier, E. R. Cosman, A. J. Lazzarini, H. E. Wegner, J. D. Garrett, and F. Pühlhofer

Phys. Rev. C 15, 654 (1977) - Published 1 February, 1977

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Evaporation residues of reactions between ${}^{24, 25, 26,}{Mg}$ , ${}^{27}{Al}$ , and ${}^{28}{Si}$ as targets and 100-170 MeV ${}^{35}{Cl}$ and 130 MeV ${}^{32}S$ beams and also between ${}^{28}{Si}$ and 117.5 MeV ${}^{28}{Si}$ ions were measured at small forward angles using a time-of-flight telescope. The mass distributions of the products show a complex structure, which is shown to vary smoothly with beam energy and target mass. A dominant decay mode of the compound nucleus can be assigned to each residue mass using the shape of the angular distribution. An evaporation model calculation predicts qualitatively the main features of the mass distributions.

NUCLEAR REACTIONS ${}^{35}{Cl}$ + ${}^{24, 25, 26}{Mg}$ , ${}^{28}{Si}$ fusion, $E = 145.6$ MeV. ${}^{35}{Cl}$ + ${}^{27}{Al}$ fusion, $E = 100, 110, 120, 130, 140, 145.6, 170$ MeV; $σ (θ)$ at 170 MeV. ${}^{32}S$ + ${}^{24, 25, 26}{Mg}$ , ${}^{27}{Al}$ , ${}^{28}{Si}$ fusion, $E = 130$ MeV; $σ (θ)$ for ${}^{32}S$ + ${}^{27}{Al}$ . ${}^{28}{Si}$ + ${}^{28}{Si}$ fusion, $E = 117.5$ MeV. Comparison of mass distribution of evaporation residues with statistical particle evaporation calculations.

Spectroscopy of high spin states in ${}^{23}{Na}$ using the ${}^{12}C ({}^{12}C, p γ) {}^{23}{Na}$ reaction

G. J. KeKelis, A. H. Lumpkin, K. W. Kemper, and J. D. Fox

Phys. Rev. C 15, 664 (1977) - Published 1 February, 1977

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Particle- $γ$ -ray angular correlations have been performed using the ${}^{12}C ({}^{12}C, p γ) {}^{23}{Na}$ reaction at the resonant laboratory energy of 38.82 MeV. Branching ratios, mixing ratios, and lifetimes are determined for the $γ$ decay of states up to 13 MeV excitation energy in ${}^{23}{Na}$ . These results are combined with the ${}^{12}C$ ( ${}^{12}C$ , ${}^{8}{Be}$ ) ${}^{16}O$ , ${}^{12}C ({}^{12}C, d) {}^{22}{Na}$ , and ${}^{12}C ({}^{12}C, p) {}^{23}{Na}$ reaction analyses to produce the following spin and parity assignments: 6.114 MeV ( $\frac{11}{2^{+}}$ ), 6.235 MeV ( $\frac{13}{2^{+}}$ ), 7.267 MeV ( $\frac{13}{2^{+}}$ ), 9.038 MeV ( $\frac{15}{2^{+}}$ ), and 9.803 MeV ( $\frac{11}{2^{+}}$ ). Shell-model calculations are superior to Nilsson model calculations in describing these results.

NUCLEAR REACTIONS ${}^{12}C ({}^{12}C, p γ)$ , $E_{{}^{12}C} = 38.82$ MeV, measured lifetimes, branching ratios, and $p - γ$ angular correlations. Deduced $J^{π}$ of ${}^{23}{Na}$ levels. Compared results with shell and Nilsson models.

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Analysis of four-body final states: Nonrelativistic

${}^{37}{Cl} ({}^{3}{He}, p) {}^{39}{Ar}$ reaction

Analyzing power for ${}^{4}{He} (p, p) {}^{4}{He}$ scattering at 11.93 and 17.00 MeV

Elastic scattering of protons by helium 4: New experiments and analysis

Correlations and dipole excitations in nuclei

${}^{3}{He} (γ, 2 p) n$ reaction

8.92 MeV doublet and 8.98 MeV level in ${}^{15}O$

Off-energy-shell generalization of the results in potential scattering

Observation of a narrow state at 10.459 MeV in ${}^{15}O$ via the ${}^{14}N (p, γ) {}^{15}O$ reaction

Empirical evidence for the importance of coherence effects in the ${}^{34}S (p, α) {}^{31}P$ reaction

Absolute resonance strengths in the ${}^{20, 21, 22}{Ne} (p, γ) {}^{21, 22, 23}{Na}$ and ${}^{21}{Ne} (p, p_{1} γ) {}^{21}{Ne}$ reactions

${}^{140}{Ce} (d, p) {}^{141}{Ce}$ at 17 MeV

Direct population of $j_{p} + j_{n} = J_{max}$ two-particle states in ${}^{206, 208, 210}{Bi}$

Neutron total cross sections and resonance parameters of ${}_{29}^{63}{Cu}$ and ${}_{29}^{65}{Cu}$ . I

High-resolution neutron capture cross sections in ${}^{63}{Cu}$ and ${}^{65}{Cu}$ . II

$3^{-}$ octupole states in the even Cd nuclei

Intermediate coupling in ${}^{203, 205}{Tl}$

Levels in ${}^{97}{Ru}$ from ${}^{96}{Ru} (d, p)$

Mass systematics of evaporation residues from ${}^{35}{Cl}$ - and ${}^{32}S$ -induced fusion on light targets

Spectroscopy of high spin states in ${}^{23}{Na}$ using the ${}^{12}C ({}^{12}C, p γ) {}^{23}{Na}$ reaction

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