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The (d, 3 He) reaction has been studied for targets of 16 O, 40 Ca and 58 Ni, to test DWBA predictions at high incident deuteron energy. Spectroscopic factors are obtained in local, zero-range, and in nonlocal, finite-range approximations.

Angular distributions of the ground state transitions in the reactions 11 B( 14 N, 15 O) 10 Be, 11 B( 14 N, 13 C) 12 C, 12 C( 11 B, 12 C) 11 B and 13 C( 12 C, 13 C) 12 C have been measured with a magnetic spectrometer as an identification system. The first two reactions (angular momentum transfer l = 2) measured at 41, 77 and 113 MeV show a clear damping of the oscillatory structures in the angular distributions. This effect was qualitatively reproduced by DWBA calculations which take into account a recoil phase, thus showing that the damping of the structures is due to the recoil of the transferred particle on the system. The reaction 11 B( 12 C, 11 B) 12 C ( l = 2) at 87 MeV with Q = 0 is well reproduced by the calculations, whereas the 13 C( 12 C, 13 C) 12 C reaction as the only l = 0 transition is in complete disagreement with theoretical expectations.

The angular distributions of inelastically scattered 155Mev protons from excited states of Li/sup 6/, Li/sup 7/, Be/sup 9/, B/sup 10/, B /sup 11/, C/sup 12/, and Ca/sup 40/ are measured. The measurements are used to determine the angular momentum, parity, excitation probability, etc. for these excited states. (T.F.H.)

The angnlar distributions of inelastic scattering of protons have been studied for the low-lying excited states of /sup 28/Si, /sup 32/S, and /sup 40/Ca. Comparison has been made with results obtained by inelastic scattering of electrons. (auth)

We have measured the differential cross sections from 8 to 35° of 155 MeV protons on 23Na, 27Al, 28Si, 31P, 32S, 39K and 40Ca nuclei. Scattered protons were analysed with a magnetic spectrometer with 0.5% overall resolution. Most of the observed levels are of a collective character corresponding to E2 or E3 excitation. By using the plane wave impulse approximation, we deduced the reduced transition probabilities. We give comparisons with other experimental results and with rotational model and core particle coupling predictions.

Quasi-free proton-proton scattering at 6 Li, 7 Li and 9 Be has been studied at 156 MeV with an overall energy resolution of 2.1 MeV for 6 Li and 1.7 MeV for 7 Li and 9 Be. Two magnetic spectrometers, multi-channel scintillation detectors or spark chambers and an on-line computer were used. Summed energy spectra and angular correlations of the components of these spectra are given. The results suggests 1p + 2s configuration mixing for external protons in 6 Li and 7 Li. The (1s) −1 splitting is observed for both nuclei.

Resume We have studied summed energy spectra displayed by protons emitted in coincidence in (p, 2p) reactions induced by 155 MeV incident protons on the following target nuclei: Li 6 , Li 7 , B 10 , B 11 and C 12 . Two telescopes each with 2 plastic scintillators and 1 NaI total absorption scintillator were used to detect the product protons. The summed energy spectra exhibit generally 2 well defined peaks which define the binding energy. Angular correlation distributions were obtained for those events under each summed energy peak for which the 2 product protons are emitted in a plane symmetrically on each side of the incident beam and have approximately the same energy. Applying the Born approximation and neglecting nuclear absorption, we have deduced momentum density distributions for protons in the target nuclei. The high binding energy proton distribution presents a maximum for zero momentum, characteristic of an s state, the lower-binding energy proton distribution presents a minimum for zero momentum, characteristic of a p state, except in the case of Li 6 . Parameters of these distributions are given which permit comparison among the various target nuclei.

The elastic scattering of 84Kr from 208Pb and 232Th has been studied; strong-absorption radii R are deduced. A decrease of the radius parameter r, defined by R = r(A 1 1 3 + A 2 1 3 , is found with regard to reactions with lighter ions, which can be quite well fitted by an optical spherical model. Differences observed in scattering from 208Pb and 232Th may be due to deformation effects. Interaction barriers are estimated.

Direct reactions induced by 14 N on 12 C at 78 MeV are studied. Angular distributions of the inelastic scattering and transfer of one and two nucleons have been measured. The DWBA analysis of the transfer based on the theory of Buttle and Goldfarb extended well above the Coulomb barrier has been performed. Using the Barshay and Temmer theorem, the isospin conservation in one-nucleon transfer reactions between heavy ions has been tested.

We have measured the differential cross sections from 8° to 40° of 155 MeV protons on some f 7 2 nuclei (48Ti, 52Cr, 56Fe, 51V and 59Co). Quadrupole excitations in even f 7 2 nuclei have been found with a more pronounced “collective” behaviour for N ≠ 28 nuclei. A systematic of the properties of the first 2+ levels shows typical shell effects at N = 28. Octupole excitations have also been well established, which do not show strong shell effects, and are distributed among different levels; a quite good agreement is found with the location of particle-hole states belonging to the ( f 7 2 )( d 3 2 ) −1 and ( f 7 2 )(2 s 1 2 ) −1 configurations as predicted by (p, 2p) experiments. Concerning the 51V and 59Co odd nuclei, we have found strong E2 and E3 transitions which seem to be connected with core excitations. Moreover, our results seem to establish the presence of E3 excitations corresponding to the (2 s 1 2 ) −1 single-hole states determined by (p, 2p) experiments.

A heavy-ion reaction leading to two members of the same isospin multiplet in the exit channel has been studied. The angular distribution is symmetric about 90°. This proves the “indentity” of mass 13 mirror nuclei, as seen from a nuclear reaction in which isospin is concerned.

Targets of 208Pb, 232Th and 238U have been bombarded with 500 MeV 84Kr ions in an attempt to observe superheavy nuclei which could be formed by fusion. The mass identification was done in flight on recoiling nuclei. No superheavy compound nuclei were observed from any of the targets. Upper limits of formation cross sections were found of ≈ 1 νb for Pb, 5 νb for Th and 80 νb for U targets.

A proton beam of 155 Mev was obtained from a synchrotron. The angular correlations and energies of the resulting particles were studied. The probability density was investigated for the reactions. (R.E.U.)