Search for Charmed F Mesons in Electron-Positron Collisions with the Crystal Ball.

In this work an experimental search for the production of the charmed F and F* mesons in e('+)e('-) collisions is presented. The data for this analysis were obtained over a center of mass energy region from 3.86 GeV to 4.5 GeV with the Crystal Ball detector at SPEAR. The inclusive (eta) production cross section has been measured as a function of the center of mass energy. It was found to be almost constant with no indication for an significant increase which was cited as evidence for F production by a previous experiment. A search for F(')F, F*(')F and F*(')F* production with the decay F('(+OR-)) (--->) (eta)(pi)('(+OR-)) has also been made, but no signal was observed. Upper limits for (sigma)(,F('(*))F('(*))). BR(F('(+OR-)) (--->) (eta)(pi)('(+OR -))) are given for various F and F* masses. The measurements presented here are inconsistent with results from earlier experiments which had been used to establish the existence of the F mesons. The inclusive (gamma) spectrum at E(,cm) = 4.33 GeV has also been used to obtain upper limits on F* production. These results disagree with theoretical expectations for the F*(')F* production cross section for the F and F* masses quoted by other experiments. In connection with this analysis the cross section for D* production was also measured at E(,cm) = 4.33 GeV and was found to be 7.4nb (+OR-) 1.1nb (+OR-) 1.3nb.