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Inelastic scattering of 84 Kr on 232 Th has been measured at E =371 and 450 MeV and at different angles using the particle-gamma coincidence technique. It is found that for distances of closest approach smaller than about 20 fm the scattering of Kr on Th is mostly inelastic. At forward angles, the data are in agreement with predicted values from a Coulomb excitation program, but some differences are observed at backward angles.

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.

The low-lying excited states of 194, 196, 198, 200 Pb have been studied through the de-excitation γ-rays following the reactions Os( 12 C, 4n), W( 16 O, 4n) and Re( 14 N, 5n). Prompt and delayed spectra, γ-γ coincidences, γ-ray angular distributions and γ-ray time distributions have been obtained. Half-lives were measured for the 12 + level in the four isotopes, for the 9 − level in 194, 196, 200 Pb, for the 7− level in 200 Pb and for the 5− level in 196, 198 Pb. The results of microscopic calculations, performed with either a Gaussian interaction or a surface delta interaction, are compared to the experimental level schemes and transition probabilities, and discussed.

Coulomb excitation experiments have been performed on the two stable odd-mass tellurium isotopes using a N 3+ beam from the Orsay cyclotron. The reduced excitation probabilities of the following levels: 439.2 keV (3/2 + ) and 505.2 keV (5/2 or 3/2 + ) in 123 Te, 443.5 keV(3/2 + ), 463.4 keV (5/2 + ) and 671.3 keV (5/2 + ) in 125 Te were measured by this method. Some B (E2) and B (M1) transition probabilities are deduced from experiments. The results are discussed in terms of de Shalit's model and Kisslinger and Sorensen's calculations.

L'etude par spectroscopie γ des isotopes pairs du tellure de masse 118 a 126 permet d'etendre la systematique des niveaux ayant une energie de 0 a 3 MeV. Les tellures-122 a 130 ont ete egalement etudies par excitation coulombienne ainsi que 124Sn avec des ions 14N3+ ayant une energie de 44 et 48 MeV.

La mesure de la radioactivite du noyau residuel nous a permis d'atteindre la reaction p, 2p sur les isotopes 49, 48 et 47 du titane, a 155 MeV. Les sections efficaces correspondantes sont respectivement : 11,8 ± 2,65 ; 26,6 ± 5,5 ; 21,5 ± 9,4 mb. La difference entre les deux premieres valeurs est grande, en depit des erreurs relatives. En utilisant le formalisme de Benioff, nous avons essaye de localiser l'energie des niveaux de la sous-couche 1 d 5/2 dans les noyaux de titane. Il semble que l'energie d'excitation de l'etat de trou proton 1 d 5/2 dans 47Sc pourrait etre estimee a 9,1 ± 1,3 MeV.