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Triple-differential cross sections of charged pions were measured for collisions of Ne projectiles at E/A = 800 MeV with NaF, Nb, and Pb targets. The reaction plane was estimated event by event from the light-baryon momentum distribution. For heavy targets, preferential emission of charged pions away from the interaction zone towards the projectile side was observed in the transverse direction. Such a preferential emission, which is not predicted by cascade calculations, may be attributed to a stronger pion absorption by the heavier spectator remnant.

Deuteron spectra at laboratory angles from 30 to 90 were measured in a+(Pb, Cu, and C) collisions at 800, 600, and 200 MeV/nucleon, and a+(Pb and C) collisions at 400 MeV/nucleon. The coalescence relation between protons and deuterons was examined for the inclusive part of the spectra. The size of the interacting region was evaluated from the observed coalescence coefficients. The rms radius is typically 4 -5 fm, depending of the target mass. The proton and deuteron energy spectra corresponding to central collisions were fitted assuming emission from a single source moving with a velocity intermediate between that of the projectile and the target. The extracted "temperatures" are independent of the nature of the emitted particle, indicating that the fragments have a common source. The best fits were achieved for 200and 400-MeV/nucleon reactions. Spectra of deuteron-like pairs, including real deuterons and neutron-proton pairs that may be contained in a larger nuclear cluster, are compared to the prediction of an intranuclear cascade model incorporating a clustering algorithm based on a classical coalescence prescription. Best agreements between experimental and predicted deuteron-like spectra occur for 800and 600-MeV/nucleon collisions.

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