Decay of the 21/2− isomer in211Bi and structure of thevg 9 2/2 πh 9/2 levels

Gamma rays and conversion electrons have been measured in²¹¹Bi populated by the²⁰⁹Bi(t,p) reaction, and the near yrast levels were observed up to 21/2^?. The 21/2^? state is isomeric withT _1/2=70(5) ns. No alpha decaying isomer was found in²¹¹Bi. ObservedM1 transitions reveal mixing of the²¹⁰Pb parent states in the levels of²¹¹Bi. The levels and transitions are well reproduced by the shell model with experimental matrix elements and pure configurations.     

Convergence of relaxation algorithms by averaging

Adaptive relaxation algorithms use anti-jamming schemes that require either a large amount of computation or a large amount of memory. In this paper we present a non-adaptive approach that possesses substantial cómputational and memory advantages over the adaptive schemes. The approach uses averaging and may be applied whenever the relaxation algorithm's point-to-set maps satisfy appropriate assumptions.This work was supported by the Air Force Office of Scientific Research under Contract AFOSR-85-0097.     

Trianguläre interpolation

Triangular interpolation problems (problems with biorthogonal polynomial sequence) are studied. Convergence of the corresponding interpolation series is investigated. It is shown that the interpolation polynomials form a basis in appropriate nuclear Fréchet spaces. The results are applied to the interpolation of weighted remainders and the Abel-Gončarov interpolation problem.      

Search for heavy neutral leptons in e+e− annihilations at 29 GeV

A search was made in 29 GeV e⁺e^? annihilations for heavy, neutral leptons decaying to e^±X^?(ν), where X is a muon or charged meson. Six events with isolated e^±X^? pairs were found for an intergrated luminosity of 106 pb^?1. The expected background is 5.5 ± 2.2 events. Limits on $\text{σ}\text{s}\text{?}\text{B}$ depend on mass and range from 8 to 20 × 10^?5 nb.