Nuclear orientation ofTb160in Tb single crystal

g-factor of the 4 1 + rotational state of160Dy

“…Our directional correlation measurements show that the 7-transitions of 1003, 1103 and 1115 keV are very pure E1 transitions in agreement with the precise NO-data by Marshak et al [10] and in disagreement with earlier nuclear orientation work. The derived very small values for the El~M2 mixing parameters show only small deviations from the data quoted by Marshak et al [10].…”

Low temperature nuclear orientation observations of severe neutron activation damage in ( 160 Tb)TbNiAl 4

“…The definitive LTNO study of 160 Tb in neutron irradiated, single crystal elemental Tb by the Berlin group [3] showed unequivocally that no subsequent heat treatment was required post neutron irradiation in order to reproduce within experimental error the more precise NMRON magnetic dipole and electric quadrupole hyperfine interaction parameters obtained on implanted single crystal samples [4]. Our observations show, in striking contrast, complex metal hosts containing 160 Tb represent a far more problematic environment for self annealing of the inevitable radiation damage from high energy prompt gamma emissions following neutron activation.…”

“…While exploiting this capability in a series of RE intermetallic single crystal alloys it was found that for 160 Tb in neutron irradiated, unannealed samples the LTNO directional gamma anisotropy was lower than anticipated hyperfine parameters would predict. For example, one disturbing anomaly was the surprisingly low gamma anisotropy observed from 160 Tb nuclei in unannealed (Pr 0.6 Nd 0.3 Tb 0.1 )NiAl 4 [5] relative to ( 160 Tb)Tb [3]. In our paper a sample of extensive LTNO studies of the terminal compound, TbNiAl 4 , is presented with a view to understand the basic origins of the attenuated LTNO.…”

“…In particular, rare earth (RE) based amorphous alloys [1] and multi-layer structures have yielded information on preferred directions of the local ionic RE moments under various applied magnetic field strengths, assuming parallelism between electronic magnetic moment, magnetic hyperfine field (MHF), and, in those cases where required, the principal electric field gradient (EFG) [2]. For these latter studies a common approach has been the use of the strongly quadrupolar LTNO probe, 160 Tb, in unannealed samples, post the thermal neutron activation; unannealed, presumably, in part due to the fragility of the samples under study and in part due to the established absence of significant neutron activation damage observed in the extensive Berlin LTNO and NMRON studies on 160 Tb in elemental Tb [3,4]. Our paper highlights a potential fallacy of adopting this sample preparation approach, for complex metal hosts.…”

Partial derivation of transformation properties of quarks and leptons

“…Our basic tool will be the freedom from Adler-Bell-Jackiw anomalies [2] required for the consistent renormalization and unitarity of a gauge field theory. Such considerations have already been successfully used in the past [3] to show that there is no need to pre-assign the Y-charges of the fermions of the one-generation standard model but rather they can be determined by the constraints of anomaly freedom once the fermion content and the gauge group are given, if QED is assumed to be vector-like. Our goal here is to go further using the same anomaly constraints.…”