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First measurements of the Collins and Sivers asymmetries of charged hadrons produced in deep-inelastic scattering of muons on a transversely polarized 6LiD target are presented. The data were taken in 2002 with the COMPASS spectrometer using the muon beam of the CERN SPS at 160 GeV/c. The Collins asymmetry turns out to be compatible with zero, as does the measured Sivers asymmetry within the present statistical errors.

An amplitude analysis of an exclusive sample of 5765 events from the reaction π − p → η ′ π − p at 18 GeV/c is described. The η ′ π − production is dominated by natural parity exchange and by three partial waves: those with J P C = 1 −+ , 2 ++ , and 4 ++ . A mass-dependent analysis of the partial-wave amplitudes indicates the production of the a2(1320) meson as well as the a4(2040) meson, observed for the first time decaying to η ′ π − . The dominant, exotic (non-qq) 1 −+ partial wave is shown to be resonant with a mass of 1.597 ± 0.0102 and a width of 0.340 ± 0.040 ± 0.050 GeV/c 2 . This exotic state, the π1(1600), is produced with a t dependence which is different from that of the a2(1320) meson, indicating differences between the production mechanisms for the two states.