The reaction e+e~e+e m. m has been analyzed using 97 pb ' of data taken with the Crystal Ball detector at the DESY e e+ storage ring DORIS II at beam energies around 5.3 GeV. For the first time we have measured the cross section for yy~m. m. for n m invariant masses ranging from threshold to about 2 GeV. We measure an approximately flat cross section of about 10 nb for 8'=m 0 0 (0.8 GeV, which is below 0.6 GeV, in good agreement with a theoretical prediction 'tr n' based on an unitarized Born-term model. At higher invariant masses we observe formation of the ft(1270) resonance and a hint of the fo(975). We deduce the following two-photon widths: I rr(f, (1270)) =3.19+0. 1620 z, keV and I "(fo( 975)) (0.53 keV at 90% CL. The decayangular distributions show the m~system to be dominantly spin 0 for W &0.7 GeV and spin 2, helicity 2 in the f, (1270) region, with helicity 0 contributing at most 22% (90% C.L.).

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We con rm the existence of the two I G (J PC ) = 0 + (0 ++ ) resonances f 0 (1370) and f 0 (1500) reported by us in earlier analyses. The analysis presented here couples the nal states 0 0 0 , 0 0 and 0 of pp annihilation at rest. It is based on a 3 3 K{matrix. We nd masses and widths of M = (1390 30)MeV , ; = (380 80)MeV and M = (1500 10) MeV , ; = (154 30)MeV , respectively. The product branching ratios for the production and decay i n to 0 0 and of the f 0 (1500) are (1:27 0:33) 10 ;3 and (0:60 0:17) 10 ;3 , respectively.

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