The first experimental investigation of the near-threshold cross section for incoherent $pi^-$ photoproduction on the deuteron $gamma$ d -> $pi^-$ pp is presented. The experimental technique involved detection of the ~131 MeV gamma ray resulting from the radiative capture of photoproduced $pi^-$ in the target. The total cross section has been measured using an unpolarized tagged-photon beam, a liquid-deuterium target, and three very large NaI(Tl) spectrometers. The data are compared to theoretical models that give insight into the elementary reaction $gamma$ n -> $pi^-$ p and pion-nucleon and nucleon-nucleon final-state interactions.
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