Branching fraction measurements of χc0 and χc2 to π0π0 and ηη

Using a sample of 1.06×10⁸ ψ^' decays collected by the BESIII detector, χ_c0 and χ_c2 decays into π⁰π⁰ and ηη are studied. The branching fraction results are Br(χ_c0→π⁰π⁰)=(3.23±0.03±0.23±0.14)×10^-3, Br(χ_c2→π⁰π⁰)=(8.8±0.2±0.6±0.4)×10^-4, Br(χ_c0→ηη)=(3.44±0.10±0.24±0.2)×10^-3, and Br(χ_c2→ηη)=(6.5±0.4±0.5±0.3)×10^-4, where the uncertainties are statistical, systematic due to this measurement, and systematic due to the branching fractions of ψ^'→γχ_cJ. The results provide information on the decay mechanism of χ_c states into pseudoscalars.