Using the CLEO II detector, we have measured the differential cross sections for exclusive two-photon production of light pseudoscalar mesons 0 , , and Ј. From our measurements we have obtained the form factors associated with the electromagnetic transitions ␥*␥→meson. We have measured these form factors in the momentum transfer ranges from 1.5 to 9, 20, and 30 GeV 2 for 0 , , and Ј, respectively, and have made comparisons to various theoretical predictions. ͓S0556-2821͑98͒01001-7͔

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CLEO has studied B decays to the nal states ` , ` , and !` , wherè = e or. We fully reconstruct these modes using a measurement of the missing energy and momentum in each event to infer the neutrino momentum. With the B 0 and B + modes combined according to isospin predictions for the relative partial widths, we obtain B(B 0 ! ?`+) = (1:8 0:4 0:3 0:2) 10 ?4 and B(B 0 ! ?`+) = (2:5 0:4 +0:5 ?0:7 0:5) 10 ?4 , where the errors are statistical, systematic and the estimated model-dependence. We also estimate jV ub j = (3:3 0:2 +0:3 ?0:4 0:7) 10 ?3 .

We observe a narrow enhancement near 2m(p) in the invariant mass spectrum of pp pairs from radiative J/psi-->gammapp decays. No similar structure is seen in J/psi-->pi(0)pp decays. The results are based on an analysis of a 58 x 10(6) event sample of J/psi decays accumulated with the BESII detector at the Beijing electron-positron collider. The enhancement can be fit with either an S- or P-wave Breit-Wigner resonance function. In the case of the S-wave fit, the peak mass is below 2m(p) at M=1859(+3)(-10) (stat)+5-25(syst) MeV/c(2) and the total width is Gamma<30 MeV/c(2) at the 90% confidence level. These mass and width values are not consistent with the properties of any known particle.

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We have searched for two-body charmless hadronic decays of B mesons. Final states include ππ, Kπ, and KK with both charged and neutral kaons and pions; πρ, Kρ, and K * π; and Kφ, K * φ, and φφ. The data used in this analysis consist of 2.6 million BB pairs produced at the Υ(4S) taken with the CLEO-II detector at the Cornell Electron Storage Ring (CESR). We measure the branching fraction of the sum of B 0 → π + π − and B 0 → K + π − to be (1.8 +0.6+0.2 −0.5−0.3 ± 0.2) × 10 −5 . In addition, we place upper limits on individual branching fractions in the range from 10 −4 to 10 −6 .