From the interactions of a deuteron beam in a liquid-hydrogen target at energies near the d+p-+ 3 He + 77 threshold, r? events were selected on the basis of the momentum-analyzed 3 He with a background of less than 2%. This opens the way to a 3 He-tagged r\ beam at Saturne, with a possible flux of 10 4 -10 5 77' s per pulse. The present data allow an evaluation of the cross section down to less than 0.5 MeV above threshold. The deuteron tensor analyzing power f 20 has also been measured: The small negative value found at threshold (-0.15 ±0.05) seems incompatible with models based on one-pion exchange.

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The total cross section for ω production in the pp → ppω reaction has been measured at five c.m. excess energies from 3.8 to 30 MeV. The energy dependence is easily understood in terms of a strong protonproton final state interaction combined with a smearing over the width of the state. The ratio of near-threshold φ and ω production is consistent with the predictions of a one-pion-exchange model and the degree of violation of the OZI rule is similar to that found in the π − p → nω/φ reactions.

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The reaction pp ! pp 1 N has been studied at three energies (T p 1520, 1805, and 2100 MeV) and six angles from 0 ± up to 17 ± (laboratory). Several narrow states have been observed in missing mass spectra at 1004, 1044, and 1094 MeV. Their widths are typically 1 order of magnitude smaller than the widths of N ‫ء‬ or D. Possible biases are discussed. These masses are in good agreement with those calculated within a simple phenomenological mass formula based on color magnetic interaction between two colored quark clusters. [S0031-9007(97)