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We present a measurement of {\eta} meson production in photon-photoninteractions produced by electron-positron beams colliding with \sqrt{s}=1 GeV.The measurement is done with the KLOE detector at the \phi-factory DA{\Phi}NEwith an integrated luminosity of 0.24 fb^{-1}. The e^+e^- --> e^+e^-{\eta}cross section is measured without detecting the outgoing electron and positron,selecting the decays {\eta}-->{\pi}^+{\pi}^-{\pi}^0 and{\eta}-->{\pi}^0{\pi}^0{\pi}^0. The most relevant background is due to e^+e^---> {\eta}{\gamma} when the monochromatic photon escapes detection. The crosssection for this process is measured as {\sigma}(e^+e^- -->{\eta}{\gamma}) =(856 \pm 8_{stat} \pm 16_{syst}) pb. The combined result for the e^+e^--->e^+e^-{\eta} cross section is {\sigma}(e^+e^- -->e^+e^-{\eta}) = (32.72 \pm1.27_{stat} \pm 0.70_{syst}) pb. From this we derive the partial width{\Gamma}({\eta}-->{\gamma}{\gamma}) = (520 \pm 20_{stat} \pm 13_{syst}) eV.This is in agreement with the world average and is the most precise measurementto date.

Measurement of {\eta} meson production in {\gamma}{\gamma} interactions and {\Gamma}({\eta}-->{\gamma}{\gamma}) with the KLOE detector