G. Dumont

Magnetic moment of the 112− isomer of 125Te

Abstract In nuclear orientation experiments on 125m Te, implanted in iron, the anisotropy of the 109.5 keV γ-ray, from the 11 2 − − 3 2 + transition has been observed. Using the hyperfine field of tellurium in iron, the magnetic moment of the 11 2 − state was derived: μ = −(0.93 ± 0.05)n.m. The g -factor of this state is compared to values reported for the g -factor of the 9 2 − “intruder” state in 125 Te: this confirms the three-quasiparticle description of the latter state.

Dose dependence of the substitutional fraction of Xe implanted in Fe

By means of the nuclear orientation technique a systematic study of the behaviour of xenon implanted in iron has been done. Strong evidence for the dose dependence of the substitutional fraction is shown. Radiation damage during implantation is obviously the cause of this phenomenon. By means of a general mathematical model one can describe what happens during implantation. A physical two-site model derived from the general one enabled us to explain the dose dependence of the substitutional fraction. At the same time, the dependence of the substitutional fraction on other parameters as temperature and ion flux appears in the equations.

The hyperfine field of xenon nuclei at lattice sites in iron

Abstract The hyperfine field of xenon nuclei at lattice sites in iron has been determined from nuclear orientation experiments at temperatures between 11 mK and 80 mK obtained with a 3 He- 4 He dilution refrigerator. From the temperature dependence of the M4 γ-ray anisotropies of 133 Xe m and 131 Xe m implanted in iron by isotope separator, the fractions of xenon nuclei at high-field sites were determined, and a value H hf = 1510 ± 160 kG was deduced.

Lattice location of Xe in iron

Mossbauer effect following ion implantation of 8.2 d 129mXe in metallic Fe has been systematically investigated as a function of implanted dose (1012−1015 ions/cm2). The significance of these experiments is threefold. (a) These have permitted a reliable measurement of the internal magnetic field Hint at the high field site, which is believed to be a substitutional Xe site in the b.c.c. lattice of the host. The Hint value was found to be 1480±80 kOe and provides an important calibration point in the systematics of Hint at 5s‐p impurities in Fe. (b) The general shape of the spectra were found to be sensitive to the implantation dose. They suggest the existence of a few magnetically inequivalent sites, the population of which are sensitive to implantation conditions such as host temperature and implanted dose. (c) Finally, values of Hint at the sites are of interest for purposes of structural identification. There is evidence that these sites may represent Xe lattice locations having one, two, three, etc. va...