Isospin Analysis of Θ + production forbids γp → Θ + K s and allows γn → Θ + K −
نویسندگان
چکیده
The discrepancy between Θ photoproduction on proton vs. deuteron can be resolved if the photon couples much more strongly to KK than to KK̄ as indicated by the experimentally observed asymmetry between γp → Λ(1520)K and γn → Λ(1520)Ks. Significant signal-background interference effects can occur in experiments like γN → K̄Θ which search for the Θ as a narrow I = 0 resonance in a definite final state against a nonresonant background, with an experimental resolution coarser than the expected resonance width. We show that when the signal and background have roughly the same magnitude, destructive interference can easily combine with a limited experimental resolution to completely destroy the resonance signal. Whether or not this actually occurs depends critically on the yet unknown relative phase of the I = 0 and I = 1 amplitudes. We discuss the implications for some specific experiments. e-mail: [email protected] e-mail: [email protected]
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