EVIDENCE FOR RHO (1300) IN THE REACTION K- P ---> PI+ PI- LAMBDA AT 11-GEV/C
David A. Aston · OSTI OAI (U.S. Department of Energy Office of Scientific and Technical Information) · 2023
Results are presented from an analysis of the r+rr-system produced in the reaction K-p + n+r-R at 11 GeV/c observed with the LASS Spectrometer at SLAC.A clear p-w interference effect is observed, and a fit to the natural parity exchange mass distribution yields an estimate of (1.5 f 0.5)% for the branching fraction of the decay w --f r + x -.An amplitude analysis reveals that the bump in the mass distribution in the vicinity of the f2( 1270) actually contains a significant P-wave component.The mass dependence of the corresponding amplitude and phase is well described by a resonant Breit-Wigner line shape with mass (1290?$$MeV/c2, width (120?:$ MeV/c2, and small 7r+7r-elasticity.The interpretation of this state as the first radial excitation of the ~(770) is discussed.Evidence is presented for production of the ps(1690) in the r+rspectrum.