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log resonances and in the fission process.We thank H. Paetz gen<, Schieck for his permanent help in running the Universitat Koln polarized ion source even if only for an unpolarized beam.The measured correlation of charged-particle energies and angles with y-ray multiplicities indicate that the average angular momentum transferred in the capture of 4 He, 8 Be, and 12 C from 153-MeV 16 0 projectiles by a 154 Sm target increases linearly with captured mass. These incomplete-fusion processes are shown to originate from undamped peripheral collisions.

Products of the completely damped deep inelastic collisions of 120-MeV 20 Ne with 27 A1 have kinetic energies significantly larger than expected to occur from Coulomb repulsion at the time of scission. The contribution to the fragment kinetic energy from rapid rotation of the fissioning system is comparable to the kinetic energy resulting from Coulomb repulsion.There is currently a great deal of interest in the macroscopic aspects of heavy-ion-induced reactions. Particular emphasis has been placed on studies of the onset of deep inelastic reactions and corresponding decrease of the fusion probability as the projectile energy, the orbital angular momentum, the charge product (Z 1 Z 2 ), or the mass symmetry of the collision increase. 1 " 4 The fusion probability has been parametrized in terms °f ^crit> the limiting angular momentum for fusion. 5 Projectiles corresponding to partial waves of orbital angular momentum slightly greater than the limiting angular momentum for fusion may undergo strong damping of their kinetic energies producing moleculelike systems which break apart without forming a totally equilibrated compound nucleus. Significant mass transfers may occur during the life of such systems.The kinetic energies of the products of completely damped deep inelastic collisions reflect the configuration of the composite nucleus at the time of scission. We have measured the kinetic energies of the products from such collisions, 120-MeV 20 Ne projectiles with 27 A1 target nuclei. The resultant energies are found to be much larger than would be expected on the basis of Coulomb repulsion alone. Calculations suggest that approximately one-half of the observed kinetic energy results from the rapid rotation of the scissioning system.For the experiment a counter telescope employing a gridded ionization chamber 6 as a AE detector was used to detect and identify products of the reactions of 120-MeV 20 Ne projectiles with a 372-jLig/cm 2 Al target. Energy distributions and angular distributions of each element were obtained. On the basis of these distributions, products with atomic number ^12 were taken to be the evaporation residues of the 47 V compound nucleus. The measured cross section for these residues is 93 5 ±90 mb which corresponds to a limiting an-gular momentum of (33.6 ± 1.1)%. With use of a potential of the form proposed by Bass, 7 a critical distance for fusion of (0.96±0.05)(A 1 1/3 +A 2 1/3 ) F is indicated. This value is slightly dependent upon the nuclear potential choice. However, from the variation of Z crit with energy, Ngo 8 has determined a critical radius parameter of 0.96 F for the fusion of 12 C with 27 A1. Thus values less than 1.00 F seem appropriate in this mass region.The products with Z < 12 are characterized by a distinctive low-energy peak in the spectrum which becomes a more prominent part of the spectrum as the laboratory angle increases. At the larger angles, the laboratory energy spectra consist of single, relatively narrow, near-Gaussian peaks.Only the atomic numbers of the products...