Measurement of the single-spin asymmetry in the reaction π-d↑→ π0X in the beam-fragmentation region at 40 GeV and pT of up to 2 GeV/c

The single-spin asymmetry AN in the reaction π- + d↑→ π0 + X in the beam-fragmentation region at the energy of 40 GeV was investigated by using the PROZA setup installed at the U-70 accelerator of the Institute for High Energy Physics (IHEP, Protvino). It was measured to be AN = (13.6 ± 2.6(stat.) ± 2.0(syst.))% in the intervals 0.7 < xF < 1.0 and 1.0 < pT < 1.8 GeV/c. The results agree with the asymmetry of π0 mesons in the charge-exchange reaction π- + p↑→ π0 + n at the same values of the transverse momentum and beam energy. The asymmetry in the reaction K- + d↑→ π0 + X was simultaneously measured and found to be AN = (11 ± 14)% for pT > 1.2 GeV/c.