Recent Articles

Sub-barrier fusion of ${}^{58, 64}{Ni}$ with ${}^{64}{Ni}$ and ${}^{74}{Ge}$

M. Beckerman, M. Salomaa, A. Sperduto, J. D. Molitoris, and A. DiRienzo

Phys. Rev. C 25, 837 (1982) - Published 1 February, 1982

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Differential cross sections for evaporation residue formation following complete fusion of ${}^{64}{Ni}$ and ${}^{74}{Ge}$ with 171 to 215 MeV ${}^{58}{Ni}$ and ${}^{64}{Ni}$ ions were measured with high precision using a velocity selector together with a counter telescope. The resulting excitation functions for complete fusion ranged in magnitude from 10 μb to 300 mb. The excitation functions exhibited a strong response, at sub-barrier energies, to changes in the underlying nuclear structure. We interpreted these variations as evidence that the fusion proceeds through dynamic single-particle/softness-related processes. A phenomenological analysis was performed. In the analysis, we employed the Wentzel-Kramers-Brillouin method, constructed a simple interaction potential and introduced a radially-dependent effective mass. The use of the variable effective mass led to a meaningful description of our above-barrier data and to improvements towards describing our sub-barrier data.

NUCLEAR REACTIONS Complete fusion, ${}^{58}{Ni}$ + ${}^{64}{Ni}$ , ${}^{58}{Ni}$ + ${}^{74}{Ge}$ , ${}^{64}{Ni}$ + ${}^{58}{Ni}$ , ${}^{64}{Ni}$ + ${}^{64}{Ni}$ , ${}^{64}{Ni}$ + ${}^{74}{Ge}$ , $E = 171 to 215$ MeV (lab), measured $σ (E, θ)$ for evaporation residues; observed dynamic, single-particle/softness effects; performed barrier-penetration analysis.

180° elastic excitation functions for ${}^{12}C$ + ${}^{32}S$ , ${}^{13}C$ + ${}^{32}S$ , ${}^{12}C$ + ${}^{28}{Si}$ , and ${}^{13}C$ + ${}^{28}{Si}$ at low bombarding energies

Y -d. Chan, R. J. Puigh, W. L. Lynch, M. Y. Tsang, and J. G. Cramer

Phys. Rev. C 25, 850 (1982) - Published 1 February, 1982

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We have measured the elastic 180° excitation functions for ${}^{12}C$ + ${}^{32}S$ , ${}^{13}C$ + ${}^{32}S$ , ${}^{12}C$ + ${}^{28}{Si}$ , and ${}^{13}C$ + ${}^{28}{Si}$ at low bombarding energies ( $V_{CB} ≲ E_{c . m .} ≲ 1.8 V_{CB}$ ). Gross structures with features resembling those observed at higher energies were observed in the ${}^{12}C$ + ${}^{32}S$ and ${}^{12}C$ + ${}^{28}{Si}$ systems but not in the other two accompanying reactions. This systematic trend is consistent with compound nucleus level density and channel competition considerations. Conventional optical model potentials with very shallow absorption can generate gross structures comparable to the data in this energy region but over predict the number of peaks.

NUCLEAR REACTIONS ${}^{12, 13}C$ ( ${}^{32}S$ , ${}^{32}S$ ), ${}^{12, 13}C$ ( ${}^{28}{Si}$ , ${}^{28}{Si}$ ), measured elastic $σ (E; 180 °)$ ; ${}^{12}C$ ( ${}^{32}S$ , ${}^{32}S$ ) measured elastic $σ (θ)$ , $E = 55 - 99$ MeV; optical model analysis, parity dependent potential.

Resonances in the ${}^{16}O$ + ${}^{12}C$ fusion cross section between $E_{c . m .} = 12 and 20$ MeV

A. D. Frawley, N. R. Fletcher, and L. C. Dennis

Phys. Rev. C 25, 860 (1982) - Published 1 February, 1982

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A careful survey has been made of the ${}^{16}O$ + ${}^{12}C$ fusion cross section from $E_{c . m .} = 12 to 20$ MeV in order to determine which resonances in ${}^{28}{Si}$ appear strongly in the total fusion cross section. Resonances which contribute 60-80 mb to the total fusion cross section are observed at $E_{c . m .} = 13.15, 14.7, 18.0, and 18.5$ MeV. An additional six resonances which contribute 30-50 mb are observed. The resonances have widths in the range 150-300 keV. All appear to correspond to resonances which have been reported previously from studies of individual reaction channels.

NUCLEAR REACTIONS ${}^{12}C$ ( ${}^{16}O$ , $X$ ), $E_{c . m .} = 12 - 20$ MeV, measured $σ (A, θ, E)$ for $A > 16$ ; deduced $σ_{fusion} (A, E)$ ; observed resonances.

Structure and decay of the highly mixed $\frac{13}{2^{+}}$ states in ${}^{171}{Er}$

A. J. Kreiner, P. D. Bond, C. Baktash, J. Barrette, C. E. Thorn, and M. T. Collins

Phys. Rev. C 25, 866 (1982) - Published 1 February, 1982

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The previously unknown structure and decay of the lowest two $\frac{13}{2^{+}}$ levels in ${}^{171}{Er}$ have been studied following the ${}^{170}{Er}$ ( ${}^{16}O$ , ${}^{15}O$ ) reaction via a particle-gamma coincidence measurement utilizing a quadrupole-dipole-dipole-dipole spectrometer. Properties of the these levels, which are highly mixed in $K$ , are compared to quasiparticle plus rotor model calculations which reproduce the general features of the particle and gamma-ray data well.

NUCLEAR REACTIONS ${}^{170}{Er}$ ( ${}^{16}O$ , ${}^{15}O γ$ ) ${}^{171}{Er}$ , $E = 120$ MeV; measured particle gamma coincidence; deduced level energies, decay scheme.

Energy dependence of fusion cross section for ${}^{28}{Si}$ + ${}^{12}C$ by evaporation residue measurements

K. T. Lesko, D. -K. Lock, A. Lazzarini, R. Vandenbosch, V. Metag, and H. Doubre

Phys. Rev. C 25, 872 (1982) - Published 1 February, 1982

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The excitation function for production of evaporation residues from the fusion of ${}^{28}{Si}$ + ${}^{12}C$ has been studied in two experiments. In the first experiment the $γ$ -ray yields of transitions populating final state evaporation residues were measured, thereby allowing a detailed study of the bombarding energy dependence of the production of specific isotopes. More accurate absolute cross sections for evaporation residue production were measured at several energies with a gas proportional $Δ E$ solid state $E$ telescope. In this manner absolute cross sections were determined against which the $γ$ -ray data could be normalized. The fusion cross section is found to vary smoothly with bombarding energy. Further, absolute cross sections agree well with model predictions currently in vogue.

NUCLEAR REACTIONS Fusion, measured $σ_{fusion} (E)$ ; ${}^{12}C$ + ${}^{28}{Si}$ , $18.4 \leq E_{c . m .} \leq 35$ MeV. Compared with entrance channel and level density limitation models.

Exclusion of nuclear forces in heavy-ion Coulomb excitation and Coulomb fission experiments

R. E. Neese and M. W. Guidry

Phys. Rev. C 25, 881 (1982) - Published 1 February, 1982

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A simple prescription for estimating the energy at which nuclear forces begin to play a role in heavy-ion Coulomb excitation and Coulomb fission experiments is presented. The method differs from most commonly used recipes in accounting for projectile and target nucleus deformation effects. Using a single adjustable parameter the formula reproduces the energy for the onset of Coulomb-nuclear interference effects for a broad range of heavy-ion systems. It is suggested that most Coulomb fission experiments which have been done involve both Coulomb and nuclear excitation processes and should more properly be termed Coulomb-nuclear fission experiments.

NUCLEAR REACTIONS Coulomb excitation. Coulomb fission. Deduced safe energy formula.

Fusion excitation function of ${}^{58}{Ni}$ + ${}^{62}{Ni}$ at 215—275 MeV

B. Sikora, M. Blann, W. Scobel, J. Bisplinghoff, and M. Beckerman

Phys. Rev. C 25, 885 (1982) - Published 1 February, 1982

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Experimental evaporation residue excitation functions are presented for ${}^{58}{Ni}$ projectiles on ${}^{62}{Ni}$ targets. These data are analyzed for fusion radii and for the nucleus-nucleus potential at the fusion barrier. The results are compared with predictions of three potential models.

NUCLEAR REACTIONS Measured evaporation residue excitation function ${}^{58}{Ni}$ + ${}^{62}{Ni}$ , $E_{lab} 215 - 275$ MeV. Deduced fusion barrier and radius.

High-spin states in ${}^{205}{At}$

T. P. Sjoreen, D. B. Fossan, U. Garg, A. Neskakis, A. R. Poletti, and E. K. Warburton

Phys. Rev. C 25, 889 (1982) - Published 1 February, 1982

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The properties of high-spin states in ${}^{205}{At}$ have been studied with the ${}^{197}{Au}$ ( ${}^{12}C$ , $4 n$ ) ${}^{205}{At}$ reaction. In-beam measurements [with Ge(Li) detectors] of $γ - γ$ coincidences, $γ$ -ray angular distributions, and pulsed-beam $γ$ timing were made to determine the decay scheme, level energies, $γ$ -ray multipolarities, spin-parity assignments, and isomeric lifetimes. High-spin states up to $\frac{29}{2} ℏ$ were identified as either proton excitations of the ( $N = 126$ ) ${}^{211}{At}$ nucleus coupled to the ${}^{202}{Pb}$ ( $Z = 82$ ) ground state or neutron excitations of ${}^{202}{Pb}$ coupled to the ${(π h_{\frac{9}{2}})}^{3} {\frac{9}{2}}^{-}$ ground state of ${}^{211}{At}$ . The lifetime measurements of the ${\frac{25}{2}}^{+}$ 2062-keV state and the unobserved isomeric state ( ${\frac{29}{2}}^{+}$ ) above 2339 keV yielded mean lifetimes of 92(3) nsec and ∼3 μsec, respectively.

NUCLEAR REACTIONS ${}^{197}{Au}$ ( ${}^{12}C$ , $4 n γ$ ) ${}^{205}{At}$ , $E_{{}^{12}C} = 77$ MeV, measured $γ - γ$ coincidence, $γ - W (θ)$ , pulsed-beam $γ$ timing; deduced levels, $γ$ multipolarities, $J^{π}$ , $T_{\frac{1}{2}}$ , $B (E 1)$ .

${}^{238}U$ fission at energies up to 100 MeV

Chien Chung and James J. Hogan

Phys. Rev. C 25, 899 (1982) - Published 1 February, 1982

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We have previously introduced a model to calculate many of the properties of 10-100 MeV proton-induced fission of ${}^{232}{Th}$ . Included were the fissionability, spallation product yields, percentage of symmetric and asymmetric fission, the peaks of the charge dispersion curves, and the postfission neutron multiplicity. In this work, that model approach is applied to the $p$ + ${}^{238}U$ fissioning system. A comparison of the results calculated from the model to the appropriate experimental data again shows excellent agreement and further justifies the model proposed.

NUCLEAR REACTIONS, FISSION ${}^{238}U$ ( $p$ , $f$ ), $E_{p} = 10 - 100$ MeV; calculation of spallation yields and fissionability; interpretation of mass distribution and charge dispersion based on calculations of model proposed.

Correlation between angular anisotropy and fragment mass in 15 MeV proton-induced fission of ${}^{232}{Th}$

H. Kudo, Y. Nagame, H. Nakahara, K. Miyano, and I. Kohno

Phys. Rev. C 25, 909 (1982) - Published 1 February, 1982

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The angular distributions of 15 fission fragments were radiochemically obtained in the 15 MeV proton-induced fission of ${}^{232}{Th}$ . It was found that the angular anisotropies of symmetrically divided fission fragments were smaller than those of asymmetrically divided fragments. With the assumption of two kinds of saddle points, one leading to a symmetric mass division and the other to an asymmetric division, the observed angular anisotropies could be well reproduced.

NUCLEAR REACTIONS, FISSION Angular distribution in 15 MeV proton-induced fission of ${}^{232}{Th}$ , Bohr's channel theory, two kinds of saddle point configurations, mass division.

Excitation energy at scission in thermal-neutron-induced fission

G. Mantzouranis and J. R. Nix

Phys. Rev. C 25, 918 (1982) - Published 1 February, 1982

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For the thermal-neutron-induced fission of ${}^{235}U$ and ${}^{233}U$ , we extract the internal excitation energy at the scission point by use of two different methods. The first method uses experimental data for ${}^{235}U$ + $n_{th}$ on the neutrons and gamma rays emitted from doubly magic fission fragments, where the extra stability associated with shell closures makes the deformation energy small. Under the assumption that both fragments have equal temperatures, this yields an upper limit of 9.9 MeV for the total internal excitation energy at scission. The second method uses experimental data for ${}^{233}U$ + $n_{th}$ on odd-even effects in fission-fragment mass distributions and yields an average value of 5.6 MeV for the total internal excitation energy at scission when integrated over all fission-fragment kinetic energies. In both cases the internal excitation energy at scission is significantly smaller than that predicted by the one-body-dissipation theory of Swiatecki and co-workers and is instead much closer to that predicted by ordinary two-body viscosity.

NUCLEAR REACTIONS, FISSION ${}^{235}U$ + $n_{th}$ , ${}^{233}U$ + $n_{th}$ ; extracted internal excitation energy at scission point. Neutrons and gamma rays from doubly magic fission fragments, odd-even effects in fission-fragment mass distributions, one-body dissipation, two-body viscosity, temperature-dependent BCS pairing theory.

Interference effects in pion double charge exchange

S. J. Greene, D. B. Holtkamp, W. B. Cottingame, C. Fred Moore, G. R. Burleson, C. L. Morris, H. A. Thiessen, and H. T. Fortune

Phys. Rev. C 25, 924 (1982) - Published 1 February, 1982

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Pion double charge exchange ( $π^{+}$ , $π^{-}$ ) has been measured using targets of ${}^{16}O$ and ${}^{18}O$ from 80 to 292 MeV at a laboratory angle of 5°. The magnitude and energy dependence of the cross section for the double-analog transition is qualitatively described in terms of a direct double-analog amplitude and a two-step nonanalog amplitude.

NUCLEAR REACTIONS ${}^{16}O$ ( $π^{+}$ , $π^{-}$ ) ${}^{16}{Ne}$ (g.s.) and ${}^{18}O$ ( $π^{+}$ , $π^{-}$ ) ${}^{18}{Ne}$ (g.s.); $θ = 5 °$ , $E_{π} = 80 to 292$ MeV, deduced two amplitude explanation for cross-section variation.

Systematics in pion double charge exchange

S. J. Greene, W. J. Braithwaite, D. B. Holtkamp, W. B. Cottingame, C. F. Moore, G. R. Burleson, G. S. Blanpied, A. J. Viescas, G. H. Daw, C. L. Morris, and H. A. Thiessen

Phys. Rev. C 25, 927 (1982) - Published 1 February, 1982

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The initial results of a systematic investigation into pion-double-charge-exchange reactions are reported. Data consisting of angular distributions and excitation functions have been measured in an effort to determine the reaction mechanism and understand its implications for nuclear physics. Cross sections are presented for ( $π^{+}$ , $π^{-}$ ) reactions on ${}^{9}{Be}$ ${}^{12, 13}C$ , ${}^{16, 18}O$ , ${}^{24, 26}{Mg}$ , ${}^{32}S$ , and ${}^{209}{Bi}$ . Surprising systematics of the reaction as functions of pion scattering angle and energy, as well as target mass and isospin, are revealed. The data are discussed in terms of two reaction models, one involving a higher-order optical potential and the other involving multiple reaction amplitudes.

NUCLEAR REACTIONS ${}^{9}{Be}$ , ${}^{12, 13}C$ , ${}^{16, 18}O$ , ${}^{24, 26}{Mg}$ , ${}^{32}S$ , ${}^{209}{Bi}$ ( $π^{+}$ , $π^{-}$ ), $E = 100 - 300$ MeV, $θ = 5 ° - 33 °$ ; measured $σ (E; θ, A)$ , double analog and nonanalog transitions; discuss second-order optical model, deduce two-amplitude model.

Energy dependence of the $p$ - ${}^{40}{Ca}$ optical potential: A Dirac equation perspective

L. G. Arnold, B. C. Clark, E. D. Cooper, H. S. Sherif, D. A. Hutcheon, P. Kitching, J. M. Cameron, R. P. Liljestrand, R. N. MacDonald, W. J. McDonald, C. A. Miller, G. C. Neilson, W. C. Olsen, D. M. Sheppard, G. M. Stinson, D. K. McDaniels, J. R. Tinsley, R. L. Mercer, L. W. Swensen, P. Schwandt, and C. E. Stronach

Phys. Rev. C 25, 936 (1982) - Published 1 February, 1982

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The energy dependence of a relativistic optical model potential consisting of a mixture of Lorentz scalar and Lorentz vector components is determined from the analysis of $p$ - ${}^{40}{Ca}$ elastic scattering experiments from 26 to 1040 MeV.

NUCLEAR REACTIONS Dirac equation based analysis of $\vec{p}$ - ${}^{40}{Ca}$ elastic scattering, $E_{p} = 26 to 1040$ MeV. Energy dependence of empirical relativistic optical potential.

Alpha spectroscopy of nuclides produced in the interaction of 5 GeV protons with heavy element targets

J. David Bowman, Richard E. Eppley, and Earl K. Hyde

Phys. Rev. C 25, 941 (1982) - Published 1 February, 1982

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Alpha particle energies were redetermined to an accuracy of 2 to 5 keV for a group of 40 neutron-deficient nuclides with atomic numbers ranging from 65 to 88. Improved half-life values were measured for 10 of these nuclides. Weightless samples containing mixtures of these activities were prepared by use of the helium jet transport technique to remove spallation and fragmentation products recoiling from targets of U, Th, Au, and Ta bombarded with 5 GeV protons. Experimental and calibration techniques are discussed in detail. Implications of the results for the mechanism of reaction of 5 GeV protons with complex targets are briefly discussed.

RADIOACTIVITY 5 GeV $p$ + U, Th, Au, Ta; separated recoil products by helium jet; measured $E α$ , $t_{\frac{1}{2}}$ ${}^{151}{Dy}$ , ${}^{154}{Er}$ , ${}^{150}{Dy}$ , ${}^{152}{Ho}$ , ${}^{152}{Ho}^{m}$ , ${}^{151}{Ho}$ , ${}^{151}{Ho}^{m}$ , ${}^{153}{Er}$ , ${}^{152}{Er}$ , ${}^{154}{Tm}$ , ${}^{154}{Tm}^{m}$ , ${}^{153}{Tm}$ , ${}^{179}{Pt}$ , ${}^{155}{Yb}$ , ${}^{178}{Pt}$ , ${}^{177}{Pt}$ , ${}^{176}{Pt}$ , ${}^{199}{Po}^{m}$ , ${}^{198}{Po}$ , ${}^{212}{Fr}$ , ${}^{197}{Po}^{m}$ , ${}^{213}{Fr}$ , ${}^{212}{Ra}$ ; measured $E α$ ${}^{149}{Tb}$ , ${}^{211}{At}$ , ${}^{204}{Fr}$ , ${}^{222}{Ac}$ , ${}^{217}{At}$ , ${}^{218}{Rn}$ , ${}^{219}{Fr}$ , ${}^{211}{Po}$ , ${}^{214}{Po}$ , ${}^{217}{Rn}$ , ${}^{216}{At}$ , ${}^{218}{Fr}$ , ${}^{215}{At}$ , ${}^{213}{Po}$ , ${}^{212}{Po}$ , ${}^{214}{At}$ , ${}^{211}{Po}^{m}$ ; reaction mechanisms discussed.

Nuclear absorption of low energy pions and the pion-nucleus optical potential

J. A. Carr, H. McManus, and K. Stricker-Bauer

Phys. Rev. C 25, 952 (1982) - Published 1 February, 1982

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The energy dependence of the optical model parameters for low energy, 0-50 MeV, pions was determined by a compromise fit to pionic atoms, $π^{+}$ elastic scattering, and $π^{\mp}$ absorption measurements.

NUCLEAR REACTIONS Pion-nucleus optical potential, elastic scattering and absorption 0-50 MeV on various targets.

( $π^{+}$ , $p$ ) and ( $π^{+}$ , $d$ ) reactions on light nuclei

K. G. R. Doss, P. D. Barnes, N. Colella, S. A. Dytman, R. A. Eisenstein, C. Ellegaard, F. Takeutchi, W. R. Wharton, J. F. Amann, R. H. Pehl, and A. C. Thompson

Phys. Rev. C 25, 962 (1982) - Published 1 February, 1982

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The ( $π^{+}$ , $p$ ) and ( $π^{+}$ , $d$ ) reactions on $1 p$ shell nuclei are studied between $T_{π} = 32 and 81$ MeV. Cross sections both to the continuum and to discrete two body final states are given. The spectra and angular distributions of the ( $π^{+}$ , $p$ ) continuum are examined in terms of a two-nucleon pion absorption mechanism. The ${}^{12, 13}C$ ( $π^{+}$ , $p$ ) spectra of discrete states are similar to the corresponding ${}^{12, 13}C$ ( $p$ , $d$ ) spectra at the same momentum transfer. The ${}^{16}O$ ( $π^{+}$ , $p$ ) ${}^{15}O$ (g.s.) transition is found to have an abnormally small cross section relative to other transitions of similar spectroscopic strength. The two-neutron pickup ( $π^{+}$ , $d$ ) data to discrete states is the first published data on this reaction. The ( $π^{+}$ , $d$ ) reaction is found to favor strongly transitions in the $1 p$ shell of angular momentum transfer $L = 2$ . The relative strength of these $L = 2$ transitions varies the same way as the corresponding ( $p$ , $t$ ) cross sections. No $L = 0$ transitions are clearly identifiable. The ( $π^{+}$ , $d$ ) angular distributions are compared to the calculations of Betz and Kerman. The calculations reproduce well the absolute magnitude and shape of the ( $π^{+}$ , $d$ ) angular distributions but fail to predict the $L$ dependence, pion energy dependence, and possibly even the spin transfer dependence of the ( $π^{+}$ , $d$ ) cross sections.

NUCLEAR REACTIONS ${}^{12, 13}C$ , ${}^{16}O$ ( $π^{+}$ , $p$ ), ${}^{7}{Li}$ , ${}^{10}B$ , ${}^{12, 13}C$ , ${}^{16, 18}O$ ( $π^{+}$ , $d$ ) $E = 32 - 81$ MeV; measured spectral shape, $σ (θ)$ for continuum and discrete states.

Recoil and correlations in pion double scattering

D. M. Schneider, M. K. Banerjee, J. W. Van Orden, and S. J. Wallace

Phys. Rev. C 25, 979 (1982) - Published 1 February, 1982

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The contribution to the optical potential due to double scattering of a pion by a pair of correlated nucleons has been calculated for nuclear matter taking account of nucleon and delta kinetic energies. The calculation includes a variety of field theoretical effects due to crossed processes and all possible time sequences of the two scattering events including overlap in time. For sequential processes, where the first scattering is complete before the second starts, it is found that inclusion of kinetic energies of the nucleon and delta reduces the contribution drastically. The contribution of these sequential processes is about 2% of the first-order optical potential as contrasted with about 50% at $T_{π} = 140$ MeV when the fixed scatterer approximation is employed. The most important correlated double scattering contributions arise from the field theoretical effects which yield about 8% of the first-order optical potential at $T_{π} = 0 and 140$ MeV. Thus, the net contribution of correlated double scattering processes is about 10% of the first-order optical potential. Since the double scattering of the pion by a correlated nucleon pair is a major contributor to the Ericson-Ericson effect, the present work suggests reduced importance of the effect.

NUCLEAR REACTIONS Correlations, fixed scatterer approximation, LLEE effect, double scattering, recoil, pion scattering.

Proton-induced muon production from nuclei

D. L. Weiss and G. E. Walker

Phys. Rev. C 25, 991 (1982) - Published 1 February, 1982

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We study the weak proton-induced muon production reaction using the impulse approximation. The process is studied below threshold for real pion production assuming a ${}^{12}C$ target. The theoretical predictions for muon angular distributions are given for the ground state, low-lying excited states, and the energetically available nuclear continuum. The process is a very rare event using presently available beam intensities. We argue that corrections to the impulse approximation are expected to be important and indicate how to use partial conservation of axial vector current and experimental ( $p$ , $π$ ) results to obtain more reliable estimates. The reaction can be a rich additional source of information regarding the relationship between the many-body pion source current and the space and time components of the nuclear axial current. Even with the conjectured substantial increase over the impulse approximation, the subthreshold counting rate seems too low for detailed experimental investigation at this time. A simple exploratory experiment starting above pion threshold and working downward in energy is suggested.

NUCLEAR REACTIONS ${}^{12}C$ ( $p$ , $μ^{+} ν$ ) ${}^{13}C$ , $E_{p} ≃ 148$ MeV, calculated $σ (θ)$ and $σ_{T}$ impulse approximation, PCAC extensions.

${}^{12}C$ ( $t$ , $p$ ) and the ground state of ${}^{14}C$

H. T. Fortune and G. S. Stephans

Phys. Rev. C 25, 1 (1982) - Published 1 January, 1982

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Sub-barrier fusion of ${}^{58, 64}{Ni}$ with ${}^{64}{Ni}$ and ${}^{74}{Ge}$

180° elastic excitation functions for ${}^{12}C$ + ${}^{32}S$ , ${}^{13}C$ + ${}^{32}S$ , ${}^{12}C$ + ${}^{28}{Si}$ , and ${}^{13}C$ + ${}^{28}{Si}$ at low bombarding energies

Resonances in the ${}^{16}O$ + ${}^{12}C$ fusion cross section between $E_{c . m .} = 12 and 20$ MeV

Structure and decay of the highly mixed $\frac{13}{2^{+}}$ states in ${}^{171}{Er}$

Energy dependence of fusion cross section for ${}^{28}{Si}$ + ${}^{12}C$ by evaporation residue measurements

Exclusion of nuclear forces in heavy-ion Coulomb excitation and Coulomb fission experiments

Fusion excitation function of ${}^{58}{Ni}$ + ${}^{62}{Ni}$ at 215—275 MeV

High-spin states in ${}^{205}{At}$

${}^{238}U$ fission at energies up to 100 MeV

Correlation between angular anisotropy and fragment mass in 15 MeV proton-induced fission of ${}^{232}{Th}$

Excitation energy at scission in thermal-neutron-induced fission

Interference effects in pion double charge exchange

Systematics in pion double charge exchange

Energy dependence of the $p$ - ${}^{40}{Ca}$ optical potential: A Dirac equation perspective

Alpha spectroscopy of nuclides produced in the interaction of 5 GeV protons with heavy element targets

Nuclear absorption of low energy pions and the pion-nucleus optical potential

( $π^{+}$ , $p$ ) and ( $π^{+}$ , $d$ ) reactions on light nuclei

Recoil and correlations in pion double scattering

Proton-induced muon production from nuclei

${}^{12}C$ ( $t$ , $p$ ) and the ground state of ${}^{14}C$

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