Professor Brian Foster OBE, FRS

Abstract:

Evidence is presented for an I = 1 enhancement observed in the reactions K-p→Λ(Σ)K01K ±π∓ at 4.2 GeV c inciden momentum. The mass and width of the proposed new Y* are, respectively, (1553 ± 7) MeV) and (80 ± 30) MeV. A decay branching ratio Σπ (Σπ + Λπ) = (35 ± 12)% is also obtained. © 1978.

Abstract:

The backward production of the B(1235) meson is studied in the reaction K-p→Σ-π+ω. This reaction is observed in the final state Σ-π+π+π-π 0. A π+ω mass enhancement is visible in the region of the B meson for events with small |u|K- →Σ-) squared four-momentum transfer. The properties of the enhancement agree with those of the B meson. The cross section for K-p→Σ-B+ at 4.15 GeV c incident K- momentum is (3.2 ± 0.5) μb. The backward production of the B meson is compared with similar baryon exchange productions of the A1 and C(Q1) axial vector mesons observed in the same experiment. © 1978.

Abstract:

Using a spin test proposed recently by Minnaert, we determine the spin of the Ξ* (1820) resonance to be 3 2. © 1978.

Abstract:

A 2.5 standard deviation signal is observed for the decay K*-(1420) → K*-(892)π+π-. From this signal a partial width of 13.0 ± 5.0 MeV for the decay mode K*(1420)→K*(892)ππ is deduced under the assumption that the ππ system is in an I = 1 state. For the rare decay mode K*(892)→Kππ no signal is observed. The following upper limits can be given for the decay widths: ΓK*-(892) → K-π+π- < 40 keV, ΓK*-(892) → K0π-π0 < 35 keV, ΓK*0(892) → K0π+π- < 35 keV. © 1978.

Abstract:

A (Kππ)+ mass enhancement is observed in the reactions K-p → Ξ -Ko+π+πo- when events with a small (K- → Ξ-) four momentum transfer squared are selected. The signal is also visible in the reaction K-p → Ξ-π++ neutrals. The enhancement, centered at 1.28 GeV, is seen to decay preferentially into Kρ{variant} with spin-parity JP = 1+. The cross section for K-p→ Ξ-C+(1.28) with C+ → Kρ{variant} at 4.15 GeV/c incident K- momentum is (6.2 ± 0.6) μb. © 1978.