Search for charmed F mesons in e/sup +/e/sup -/ collisions with the crystal ball

Abstract

In this work an experimental search for the production of the charmed F and F* mesons in e/sup +/e/sup -/ 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 anti F, F* anti F and F* anti F* production with the decay F/sup + -/ ..-->.. eta..pi../sup + -/ has also been made, but no signal was observed. Upper limits for sigma/sub F(*) anti F(*)/ BR(F/sup + -/ ..-->.. eta..pi../sup + -/) 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/sub cm/ = 4.33 GeV has also been used to obtain upper limits on F* production. These results disagree with theoretical expectations formore » the F* anti 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/sub cm/ = 4.33 GeV and was found to be 7.4nb +- 1.3nb.« less