Photoproduction of η'-mesons with SAPHIR

The η' production was studied by searching for 5-track events from the decay chain γp → pη' → pπ+π-η (43.7%)→ p2π+2π-π0γ (23.2%/4.78%)having a total decay probability of 10.1% for the π0 branch. From this decay with only one neutral particle much less background is expected than from the 3-track decays of the γp → pη' reaction, namely → pπ+π-η (→ 2π0/2γ)or the decay pη'→ pργ → pπ+π-γ. (author)