Formation of atomic tritium clusters and condensates

We present an extensive study of the static and dynamic properties of systems of spin-polarized tritium atoms. In particular, we calculate the two-body |F,m_F>=|0,0> s-wave scattering length and show that it can be manipulated via a Feshbach resonance at a field strength of about 870G. Such a resonance might be exploited to make and control a Bose-Einstein condensate of tritium in the |0,0> state. It is further shown that the quartet tritium trimer is the only bound hydrogen isotope and that its single vibrational bound state is a Borromean state. The ground state properties of larger spin-polarized tritium clusters are also presented and compared with those of helium clusters.Comment: 5 pages, 3 figure

Changes in 5d band polarization in rare-earth compounds

X-ray resonant magnetic scattering has been used to examine the magnetic interactions coupling the rare earth and iron sublattices in the antiferromagnetic compound DyFe4Al8. Dramatic differences are observed in the temperature dependencies of the magnetic intensities depending on whether the photon energy is tuned to the Dy L2 or L3 absorption edge. Simulations suggest that thesevariations in intensity are a result of small changes in the orbital occupation and spin polarization within the 5d conduction band.JRC.E-Institute for Transuranium Elements (Karlsruhe