| This work presents the results of analysis of a meson of mass mx = 1281.0 +/- 0.8 MeV/c² and a FWHM of Gammax = 18.4 +/- 1.4 MeV/ c² seen in CLAS at Jefferson Lab in photoproduction off the proton, gammap → xp. The f1(1285), eta(1295) or both are candidates for this observed state. Neither of these states has previously been observed in photoproduction. The meson was measured in the decay modes x → etapi +pi-, K+ K¯0pi-, K -K0pi+, and rho 0gamma through detection of its charged decay products and the recoil proton.;Differential cross sections were obtained via the x → etapi +pi-, K+ K¯0pi-, and K -K0pi + decay channels from threshold up to a center-of-mass energy of 2.8 GeV, and compared to recent Regge model predictions. Dalitz analysis showed strong evidence for the f1(1285) identity, with the dominance of etapi+pi- decays via a+/-0 (980)pi∓ intermediate state and with interference consistent with a spin one particle. The relative branching fractions Gamma( KK¯pi)/Gamma(etapipi) and Gamma(rho0gamma)/Gamma(etapipi) were measured, with agreement to world data for the f 1(1285) in the former and lower than the world average for the latter. |
