Transfer of nucleons at high relative velocities

We discuss nucleon transfer between bound states of nuclei at high relative velocities. It is shown that the tails of the internal momentum distributions of the nuclear states participating in the transition strongly influence the transfer probabilities at energies between 30–90 MeV/u. Data and DWBA calculations show an exponential decrease of the cross sections in this energy regime and we dub it TGV (Transfer à Grande Vitesse).     

Structure cristallinea`295 K de la phase ferroelectrique Li0,02Na0,98NbO3

The structural determination of the Li_0.02Na_0.98NbO₃ phase has been carried out by single crystal diffraction analysis. The space group of the orthorhombic cell isPc2₁b; the cell parameters area = 5.494, b = 15.461, c = 5.551A?. The structure derives from the perovskite type; it differs from that of NaNbO₃ only by the sequence of the NbO₆ octahedra tilting and by small atomic displacements allowed by the less symmetric space group. The material is antiferroelectric along thec axis and ferroelectric alongb. The direction of the polar axis fits well with previous physical measurements.     

Study of electromagnetic transition strengths in 81Rb

High-spin states in ⁸¹Rb were excited in the fusion-evaporation reaction ⁶⁵Cu(¹⁹F, p2n)⁸¹Rb. Their lifetimes were determined by means of the recoil distance and Doppler-shift attenuation techniques. Deduced B(E2) and B(M1) transition strengths are discussed in the framework of the asymmetric rotor-plus-particle model.