SLAC - PUB - 5208 February 7 , 1990 W Note on DS Decays

The new Ds hadronic modes and recent measurements which differ substantially from previous measurements are listed in Table 1. The decay mode T?OK*+ is analogous to the pK+ and iT”“K+ modes previously observed and is seen at a comparable rate to that of (9~. The existence of these KT? decays indicates that the strength of the internal W emission dia* grams is sizable. The ox++ mode is seen only in one experiment and due to the limited statistics, it is not possible to determine if the decay is through the quasi-two body mode op”. The f% mode has been observed in the three pion Daltiz plot by E691 and confirmed by Mark III. The fox mode is predicted to occur by the weak spectator decay as the f” is believed to be the scalar particle of hidden strangeness with a mass below KK threshold. The evidence for the nla and 77’~ modes is still controversial. A previous Mark II measurement reported a rate relative to on: of 3.0fl.l and 4.8_+2.1111] for these modes respectively. Recently E691 and Mark III have set upper limits whereas NA14’ has now seen a very large Ds signal decaying to n’rc. The true value may lie somewhere in between and awaits more experimental data.