V. M. Tsupko-Sitnikov

Nuclear orientation of154EuFe,166TmGd and169YbFe and169YbGd

Nuclear orientation measurements at low temperatures have been carried out on radioactive isotopes of154Eu and169Yb in Fe and of166Tm and169Yb in Gd. Gamma-rays from169YbGd, obtained by the decay of implanted and melted sample of169IuGd, were observed to have smaller anisotropies of opposite signs compared with those from169YbFe. This may indicate that for Yb polarized in Gd electric quadrupole interaction is comparable with magnetic dipole one. Mixing ratios of the transitions in154Gd,166Er and169Tm have been made for two levels in166Er. Our analysis showed that the 3− to 3+ beta decay to the 1128 keV level in154Gd has 65(20)% Δjβ=0.

Hyperfine interactions for181Ta nuclei in the laves phases LuFe2 and GdFe2

The hyperfine magnetic fields for181Ta in the cubic (C 15) Laves phases LuFe2 and GdFe2 have been measured by the TDPAC method. At 300 K, Bhf=−20.5(4) T for LuFe2 and +19.0(5) T and +10.2(4) T for the samples of GdFe2, prepared at normal and high (7.7 GPa) pressure, have been obtained. Temperature dependence of these fields in the range 77–900 K has been also measured.

Spin-2—on-line low temperature nuclear orientation facility at YASNAPP-2 complex in Jinr Dubna

The Spin-2 facility built at YASNAPP-2 experimental complex of the Joint Institute of Nuclear Research is described. The basic parameters of SPIN-2 and YASNAPP-2 are discussed.

On the magnetic dipole moment of the153Tb ground state

Temperature dependence of the angular distribution anisotropy of the 212·0 keV gamma-ray following the decay of153Tb oriented in a gadolinium host was measured at temperatures from 16 to 70 mK. Magnetic dipole hyperfine splitting parameter a0 for153Tb(Gd) and magnetic dipole moment of the153Tb ground state were estimated to be ¦a0¦≧1·2×10−5 eV and ¦μ¦≧≧3·1 nuclear magnetons, respectively.

Hyperfine magnetic fields at rare-earth elements in ferromagnetic transition metals

Hyperfine magnetic fields for such probes as:152SmFe,152SmCo,152SmNi,155GdFe,172YbFe,172YbCo and172YbNi have been measured using PAC method. The quantitative analysis of components of these fields has been also performed.

Decay of oriented149Nd and low-lying levels in theN=88149Pm nucleus

Levels of the149Pm nucleus populated in the149Nd decay were studied by using the low-temperature nuclear orientation technique. The parent149Nd nuclei were oriented in a gadolinium host. The normalized γ-ray intensities were determined for twenty seven transitions in the daughter149Pm nucleus. The characteristics of149Pm levels at 288·2 and 425·3 keV were determined as 9/2+ and 7/2+, respectively, and the previous spin-assignments could be unambiguously confirmed for several other levels in149Pm. The substantial new information on multipole mixing ratios of γ-rays in149Pm is presented. The quasiparticle-rotor model was applied to the description of the structure of the low-lying levels in149Pm.