– 1– D S BRANCHING FRACTIONS

This note will be revised after the new CLEO measurements of thirteen D+s branching fractions (P.U.E. Onyisi et al., Phys. Rev. D88, 032009 (2013)) are added to the Particle Listings. More than a dozen papers on the D+s, most of them from the CLEO experiment, have been published since the 2008 Review. We now know enough to attempt an overview of the branching fractions. Figure 1 shows a partial breakdown of the fractions. The rest of this note is about how the figure was constructed. The values shown make heavy use of CLEO measurements of inclusive branching fractions [1] For other data and references cited in the following, see the Listings. Modes with leptons: The bottom (20.0 ± 0.9) % of Fig. 1 shows the fractions for the exclusive modes that include leptons. Measured e+νe fractions have been doubled to get the semileptonic ℓ+ν fractions. The sum of the exclusive e+νe fractions is (6.9 ± 0.4)%, consistent with an inclusive semileptonic e+νe measurement of (6.5±0.4)%. There seems to be little missing here. Inclusive hadronic KK fractions: The Cabibbo-favored c → s decay in D+s decay produces a final state with both an s and an s̄; and thus decay modes with a KK pair or with an η, ω, η′, or φ predominate (see, for example, in Fig. 1 the fractions with leptons). We consider the KK modes first. A complete picture of the exclusive KK charge modes is not yet possible, because branching fractions for more than half of those modes have yet to be measured. However, CLEO ha