Measurements of ^(3097) and ^'(3686) branching fractions for selected hadronic decays are presented. The ratio of $'.to ip branching fractions for these decays is consistent with,the ratio of branching fractions to lepton pairs, with the exception of the decays to pir and K*K for which this ratio is substantially smaller.PACS numbers: 13.25.+m, 14.40.Gx Applequist and Politzer 1 calculate, using perturbative QCD, that the width of the nonrelativistic charmed quark-antiquark bound-state (charmonium) decay to three gluons is proportional to its leptonic width. Both depend on the mass and the wave function at the origin of the charmonium system. The ratio of branching fractions of ip and ip r decays to three gluons can be written in terms of their total and leptonic widths, 2 T t and T ee \ The calculation of the width to three gluons assumes that the charmonium system is nonrelativistic, that the strong-coupling constant ot s «l, that ot s (ip) =a s (ip f ) y and that charmonium systems decay to hadrons predominantly via a pointlike annihilation into three gluons.In this Letter we present measurements of the branching fractions from the ip and ip' to five exclusive hadronic final states. We compare the theoretical prediction for B(ip'-~ggg)/B(ip-~ggg) with the measured ratio B(ip' ~X)/B(ip*X), where X is an exclusive hadronic final state. We note that the prediction is made for the total width for three-gluon decay, not for the partial widths of exclusive final states. We expect the partial widths to be functions of the wave function at the origin of the charmonium states as well since the exclusive decay proceeds through a three-gluon annihilation in this model. However, there are other factors associated with each exclusive mode (such as multiplicity) which are disregarded by this prediction and therefore we do not expect the agreement between calculation and experiment to be perfect.The data were taken with the MARK II detector at the SPEAR e + e~ storage ring located at the Stanford Linear Accelerator Center. The data sample corresponds to 427 000 produced ip*s and 1.02 x 10 6 produced ip"s. The MARK II detector has been described in detail elsewhere. 3 Briefly, charged particles are tracked by a sixteen-layer cylindrical drift chamber in a 4.1-kG axial magnetic field. The momentum resolution is 8p/p = [(0.015) 2 + (0.005/>) 2 ], 1/2 where/) is the momentum in gigaelectronvolts. Time-of-flight scintillation counters are used for particle identification. The timing resolution is 300 ps for hadrons. This provides TT/K separation for charged tracks of momenta below 1.2 GeV and proton identification below 2 GeV. Liquid-argon calorimeters with an energy resolution v/E =12%/Vz? (where E is the photon energy) are used to find photons and to discriminate hadrons from electrons. A system of steel interlaced with planes of proportional tubes is used to identify muons. This is done by detecting charged particles and ranging

A high-statistics study of $ decays into baryon final states has been done with the Mark I1 detector at SPEAR. A detailed test of baryon-antibaryon decay modes is presented. Substantial resonance formation is observed in multibody decays of the $ involving baryons. Branching ratios for a large number of decay modes are given, including the radiative decay $+pFy. The flavor-SU(3)forbidden decays $ -+~~( 1 3 8 5 ) X + charge conjugate are observed with substantial branching ratios.

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