Results are presented of an untagged e+e- → e+e- + π+π- experiment performed at PEP with the DELCO detector. In the invariant-mass range 0.7 ≤ Wππ < 2.0 GeV/c2, the QED e+e- background is identified and eliminated, and both the π+π- predictions and the μ+μ- and K+K- background substractions are normalized to the measurement of the e e+e- events. The results agree with a simple model of superposition and interference of the f0 (1270) resonance, produced with helicity 2, with a Born-term continuum. From a fit of the model to the data, the radiative width of the f0 is determined to be Γf 0→γγ = 2.70 ± 0.21 keV.
ASJC Scopus subject areas
- Nuclear and High Energy Physics