The supergroup manifold formulation of the Wess-Zumino multiplet revisited: The supercurrent and the supergravity auxiliary fields

In this paper we provide a consistent first-order group-manifold formulation of the Wess-Zumino system. It is shownhow the well-known auxiliary fields of the ($\text{1}\text{2}$, 0, 0) system arise by supplementing Bianchi identities with the “second-order constraints”; that is, those equations allowing the transition from the first order to the second order of the theory. When the ($\text{1}\text{2}$, 0, 0) multiplet is coupled to N = 1 supergravity and the torsion “second-order constraint” is implemented, we get a non-minimal set of auxiliary fields (scalar, pseudoscalar axial vector and a spinor). We argue this to be the fundamental set of auxiliary fields. The so-called “minimal set” is not coordinate invariant and can be recovered only by adding a non-geometrical constraint.     

Preparation and characterization of a set of IAEA reference air filters for quality control in air-pollution studies

Several sets of reference air filters were prepared as part of an IAEA evaluation of the performance of laboratories involved in air-pollution studies. Each set comprised three polycarbonate membrane filters, two of which were loaded with urban air particulate matter (APM) obtained in Vienna or Prague, and one unloaded filter. The filters were loaded by filtration of a suspension of the APM materials in water. The homogeneity both of bulk APM materials and of the loaded filters was evaluated and found suitable by determining several elements by instrumental neutron-activation analysis (INAA), proton-induced X-ray emission (PIXE), and micro-X-ray energy-dispersive fluorescence analysis (μ-EDXRF). After evaluation of the homogeneity, INAA, PIXE, EDXRF, atomic absorption spectrometry (AAS), inductively coupled plasma optical emission spectrometry (ICP–OES), and ICP mass spectrometry (ICP–MS) were used to characterize the filter materials and establish “target values” and their associated standard deviations for 15 elements. Problems encountered during the preparation of these unique, simulated air filters and the criteria for setting both the target values and standard deviations are presented.     

Radioanalytical methods for the accurate determination of227Ac and228Th in irradiated226Ra targets

Alpha spectrometry is proposed for the quantitative analysis of²²⁷Ac and²²⁸Th in irradiated²²⁶Ra targets. The chemical separation and the radiochemical determination is described.     

Determination of neodymium isotopes as burnup indicator of highly irradiated (U,Pu)O2 lmfbr fuel

A new counting method was developed to determine²²⁶Ra in environmental samples by separating the equilibrated²²²Rn into a liquid scintillator. The integral counting method, which was originally developed for isolated individual radionuclides, was extended to the mixture of²²²Rn and its daughters in equilibrium. The optimum measurement conditions were established by examining the energy spectrum, counting time and quenching effect. An absolute counting was practiced by extrapolating the integral counting rate-bias voltage curve with the highest gain to zero bias. The detection limit thus obtained was 3 to 4·10⁻¹³ Ci.     

Extension of Geodesic Algebras to Continuous Genus

Using the Penner–Fock parameterization for Teichmüller spaces of Riemann surfaces with holes, we construct the string-like free-field representation of the Poisson and quantum algebras of geodesic functions in the continuous-genus limit.     

Vortices in He II,current algebras and quantum knots

A canonical quantization scheme is developed for vertices in superfluid He II, using Dirac's technique for constrained hamiltonian systems. Quantization introduces in the theory in natural way the structure of the infinite Lie algebra of incompressible flows. We argue that all the topological invariants of the vortex, considered as a knot, can be regarded as observables of the system. Finally unitary representations of measure preserving flows on R³ and current algebra are discussed.     

Lie groups and gravity theories

Generalized theories of gravitation using the group manifold approach are outlined. It is suggested that free differential algebras should take the place of Lie algebras in current physical theory.     

Gravity theories with asymptotically flat instantons

We construct explicitly a gravitational instanton which is asymptotically flat and globally euclidean. The instanton is a solution of euclidean gravity coupled to a scalar field in first-order formulation. The presence of a zero in the vierbeins and the consequent non-vanishing torsion allow us to obtain non-trivial topological excitations of the metric field without changing the topologically trivial structure of the underlying (euclidean) spacetime.