Professor Brian Foster OBE, FRS

Abstract:

A fine energy scan has been performed to search for narrow states in e+e- annihilation at c.m. energies between 29.90 and 31.46 GeV. No such state has been observed. The 90% confidence upper limit on the leptonic decay width times the hadronic decay branching ratio is ΓeeBh<1.6 keV. © 1979.

Abstract:

We analyse the recent data on backward axial vector meson production which come predominantly from a large K-p bubble chamber experiment at 4.2 GeV/c. In an attempt to understand the production mechanisms, we study the isospin and SU(3) structure of A1, B, D(1285) and C(1280) production and compare this with the corresponding production of pseudoscalar, vector and tensor mesons in the backward direction. The isospin and SU(3) study shows that octet exchange is dominant but there are indications that other exchanges, lower-lying than the nucleon (Nα) trajectory, must also be important. We show that a consistent description of backward resonance production is possible, but further experiments are required to confirm this. © 1979.

Abstract:

A new determination of the QA-QB mixing angle and of the antisymmetric coupling for the vector-pseudoscalar decay of the axial vector mesons is presented. This uses information from the decay rates of the A1 and C mesons found in the study of baryon exchange processes in K-p interactions at 4.2 GeV/c combined with the decay rate B → ωπ. The consistency between the results obtained from backward produced A1 and C and diffractively produced Q1 and Q2 is discussed. © 1979.