Formation of spin-one mesons by photon-photon fusion

We have observed the formation of two spin-one mesons in γγ fusion reactions in which one photon was highly virtual. The first, consistent with being the JPC=1++ f1(1285), was seen in the final state ηπ+π- (η→γγ), as was the η’(958). We have previously reported the observation of the second spin-one state, the X(1420), in the final state K±KS0π∓ (KS0→π+π-). The formation of this state, which may be the f1(1420) observed in hadronic …