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Five neutron scattering angular distributions of239Pu were measured in the primary neutron energy range between 0.19 and 0.38 MeV. The absolute cross section results are presented in the form of coefficients of Legendre polynomial expansions. Integrated scattering cross sections are also given. Cross section calculations using a central optical model were made and their results were compared with the experimental values.

From the spectra of electrons emitted in photoelectric absorption of europiumK α radiation, theK-shell fluorescence yield of tin was determined asω K=0.857±0.010. A multiwire proportional counter, filled with methane and a small admixture of tetramethyltin was employed, as a spectrometer.

6Li+-ions accelerated electrostatically to energies of 200–390 keV are electronically excited by the beam-foil technique. The emitted light is analyzed with a Seya-Namioka VUV monochromator in the wavelength range 400–1900 å. All Li II and Li III lines known from theory — in one case emitted by an=9 level — are detected, several of them for the first time. Lifetimes of 20 Li II levels, some not measured previously, are determined after correction for cascades. The accuracy of the experimental values for several lifetimes is better than that of theoretical predictions.

Analyzing powers and cross sections for the scattering of polarized protons from Si have been measured at eight energies between 17 and 29MeV. The analysing powers show an “anomalous” behaviour and an optical model analysis yields a non-monotonic effect in the spin-orbit potential.

Mass and charge transfer was investigated for the system136Xe+208Pb at 5.9 MeV/nucleon incident energy with aΔE —E-time of flight telescope. The angle and energy integrated cross section for the strongly damped events was found to be 510 mb, very close to the total reaction cross section. The width of the mass distribution as function of the total kinetic energy loss was measured and is compared to the width of the corresponding charge distribution. An upper limit of 1 μb has been found for processes with very large mass transfer.

The (n th,α) reaction spectroscopy was done on64, 65, 67zn and77Se at the 87 m curved thermal neutron guide of the Grenoble high flux reactor. In each of the64Zn(n, α)61 Ni and67 Ni(n, α) 64Ni reactions, one line showed up corresponding to anα-particle transition to the first excited state in61Ni and64Ni withσ α1=11±3 μb and 159±20 μb respectively. In the case of the radioactive65Zn(T 1/2=244d) nucleus, two lines showed up corresponding to the ground state and the first excited state transitions in62Ni with large values ofσ α0=1.0±0.1b andσ α1=1.0±0.1b. For the77Se(n, α)74Ge reaction, the ground state and first excited transitions were present withσ α0=940±20 μb andσ α1 = 30±5 μb respectively. The spin-parity (J π) of the neutron resonance contributing at thermal energy are discussed.

The probability for the escape of a particle from an oscillating two- center potential is estimated within an exactly soluble three-dimensional model

The behaviour of interfering resonances is studied within the framework of many-channelS-matrix theory. For the case of one open channel it is shown that at high level density where one naively would expect a strong overlapping, the resonances avoid each other: one resonance accumulates almost the whole sum of the widths of all resonances while the remaining ones become nearly stable.

High spin states of142Nd have been investigated via the130Te (16O,4n)-reaction by means of in-beam gamma ray spectroscopy using compton suppressed germanium detectors of the OSIRIS-12 facility. Spins up to at least I=24ħ were assigned and parities were determined by gamma angular distribution, gamma linear polarization and singles spectra measurements. The yrast states (I≤16ħ) of142Nd have been compared with neighbouring N=82 nuclei.