Data reduction methodology for perturbed angular correlation experiments

Data reduction schemes currently used for time differential perturbed angular correlation measurements are evaluated in terms of (i) their relative effectiveness in eliminating irrelevant variables, including single counter efficiencies and spectrum time shifts; and (ii) their effectiveness in putting data in a form that can easily be fitted by theoretical correlation functions. It is pointed out that erroneous conclusions may be derived from improperly reduced data, but that properly analyzed experiments performed at four angles allow a good determination of both the time-dependent and time-independent parts of the correlation function. Correction of data for accidentals, source self-absorption and spectrum livetime differences are discussed.     

The upper critical field of superconducting polysulfur nitride, (SN)x

A measurement of the temperature and angular dependence of the upper critical magnetic field H_c² in crystals of polymeric (SN)_x is reported. A large anisotropy is observed at all temperatures with H_c²6 = 8.1 ± 0.4 kOe parallel to, and H_c²⊥ = 870 ± 80 Oe perpendicular to, the polymer axis at 0°K. The results are explained in terms of the polymeric crystal structure and fibrous morphology of (SN)_x.     

Die Bestimmung der unitärenK-Theorie vonSO(n) mit Hilfe der Atiyah-Hirzebruch-Spektralreihe

Ohne ZusammenfassungStipendiat des Schweizerischen Nationalfonds     

Branching ratios between correlated and uncorrelated two electron transitions into the K-shell of Al,Ca, Fe and Ni ions

The branching ratios between the radiative single and double electron transitions into the doubly ionized K-shell were measured as a function of the atomic number. The results are compared with various theoretical predictions.     

Hyperfine experiments on magnetic critical phenomena

The application of hyperfine techniques to the study of magnetic critical phenomena is selectively reviewed. Topics discussed are probe independence, the test of universality via measurements of static exponents, static exponents in disordered systems, and dynamic critical phenomena.Work supported in part by the National Science Foundation.     

Analysenmethoden einiger neuer Sch?dlingsbek?mpfungsmittel

Ohne Zusammenfassung