Professor Brian Foster OBE, FRS

Abstract:

The reaction e+e-→e+e-η′(9 58) has been observed by detecting the final state π+π-γ. The two-photon width of the η′ has been measured to be Γ(η′→γγ) = 5.1±0.4±0.7 keV. A search for the ι(1440) has been made in the ρ{variant}0γ final state. An upper limit has been obtained for the product Γ(ι(1440) → γ)gg), B (ι→ρ{variant}0γ) < 1.5 keV (95%CL). © 1984.

Abstract:

The production of electrons by bottom and charm hadrons has been studied in e+e- annihilation at 34.6 GeV center of mass energy. It is observed that the b quark fragmentation function is peaked at large values of the scaling variable z with 〈zb〉 = 0.84+0.15 + 0.15-0.10 - 0.11. For c quarks 〈zc〉 = 0.57+0.10 + 0.05-0.09 - 0.06 is observed. A forward-backward charge asymmetry of A = -0.25 ± 0.22 was measured in b production. © 1984.

Abstract:

The cross section for the process e⁺e^-→γγ has been measured for c.m. energies 39.5+>61 GeV and Λ+> GeV (95% confidence level) have been determined. A search for two photon final states with missing energy provided lower limits on the masses of the photino and selectron. © 1984 Springer-Verlag.

Abstract:

Production of the ppπ⁺π^- final state by two-photon scattering was observed. The cross section for γγ→ppπ⁺π^- was determined assuming phase space production. No evidence was found for the production or formation of resonances. Upper limits are given for Λ and Δ pair production, for production of ppρ{variant}⁰ and for the two-photon excitation of cc bound states. © 1984.

Abstract:

We have determined the τ lifetime in e+e- annihilations at an average centre of mass energy of 42.5 GeV, using a pressurized drift chamber close to the interaction point. We find the lifetime to be (3.18-0.75+0.59 ± 0.56) × 10-13 s. The charged weak τ coupling constant relative to that of the μ is found to be Gτ/Gμ = 0.94-0.09+0.12 ± 0.09, in good agreement lepton universality. © 1984.