Measurement of the η and η′ transition form factors at q2=112 GeV2

We report a study of the processes e+e-→ηγ and e+e-→η′γ at a center-of-mass energy of 10.58 GeV, using a 232  fb-1 data sample collected with the BABAR detector at the PEP-II collider at SLAC. We observe 20-5+6ηγ and 50-7+8η′γ events over small backgrounds, and measure the cross sections σ(e+e-→ηγ)=4.5-1.1+1.2±0.3  fb and σ(e+e-→η′γ)=5.4±0.8±0.3  fb. The corresponding transition form factors at q2=112  GeV2 are q2|Fη(q2)|=0.229±0.030±0.008  GeV, and q2|Fη′(q2)|=0.251±0.019±0.008  GeV, respectively.