[en] 63300 Photographs taken at BNL during an exposure of the 80'' deuterium-filled bubble chamber to a beam of antiprotons are used to study the neutron interactions anti pd → p/sub s/X^- at an incident momentum of 15 GeV/c. The mass recoiling against the spectator proton p/sub s/ has a range from approximately 5 to 6 GeV/c² and is determined by the beam momentum and the kinematic quantities of the spectator. A special technique for reconstructing the angle of the spectator track by constraining the curvature according to the momentum from its range provides an average accuracy of approximately 15 MeV/c² for the mass. The beam momentum was monitored by measuring non-interacting beam tracks using PEPR in an automatic mode. With a resolution of 22 +- 3 MeV/c² and a sensitivity of 10 to 20 μb per standard deviation of significance no resonance is found in the total sample of events nor in any of the topological channels. On each event the track forming the largest angle with the beam has been measured for a better determination of the vertex if the angle with the beam was greater than 20⁰ in each view. An analysis of the hypothetical reaction anti pd → p/sub s/πX for these events shows no narrow structure exceeding a significance of 3 standard deviations in either the doubly charged (exotic) or the neutral missing mass distribution