The odd-even staggering of nuclear masses was recognized in the early days of nuclear physics. Recently, a similar e ect was discovered in other nite fermion systems, such as ultrasmall metallic grains and metal clusters. It is believed that the staggering in nuclei and grains is primarily due to pairing correlations (superconductivity), while in clusters it is caused by the Jahn-Teller e ect. ...

We present a model which can explain semiquantitatively a number of the unusual properties of Yb4As3. The structural phase transition at Tc ≃ 300K is described by a band Jahn-Teller effect of correlated electrons and is interpreted as a charge ordering of the Yb ions. The low carrier concentration in the low-temperature phase follows from the strong electron correlations of the 4f-holes on the ...

A band system ofjet-cooled Au, has been located in the near infrared region of the spectrum using resonant two-photon ionization spectroscopy. The origin band is located at 13 354.15 cm-’ and the system extends more than 700 cm ~’ further to the blue. The excited state displays a radiative lifetime of approximately 28 ps, corresponding to an absorption oscillator strength offzO.0003. Accordingl...

We study charged-current neutrino cross sections on neutronrich nuclei in the mass A ∼ 60 region. Special attention is paid to environmental effects, i.e. finite temperature and density, on the cross sections. As these effects are largest for small neutrino energies, it is sufficient to study only the Gamow-Teller (GT) contributions to the cross sections. The relevant GT strength distributions ...

The spin Hamiltonian parameters for the two Cu centers A1 and A2 in the calcined catalysts CuO–ZnO are theoretically investigated using the high order perturbation formulas of these parameters for a 3d ion in tetragonally elongated octahedra. In the above formulas, the tetragonal field parameters Ds and Dt are determined from the superposition model, by considering the relative axial elongation...