  A new measurement of the rare, doubly radiative decay eta->pi^0 gamma gamma
was conducted with the Crystal Ball and TAPS multiphoton spectrometers together
with the photon tagging facility at the Mainz Microtron MAMI. New data on the
dependence of the partial decay width, Gamma(eta->pi^0 gamma gamma), on the
two-photon invariant mass squared, m^2(gamma gamma), as well as a new, more
precise value for the decay width, Gamma(eta->pi^0 gamma gamma) =
(0.33+/-0.03_tot) eV, are based on analysis of 1.2 x 10^3 eta->pi^0 gamma gamma
decays from a total of 6 x 10^7 eta mesons produced in the gamma p -> eta p
reaction. The present results for dGamma(eta->pi^0 gamma gamma)/dm^2(gamma
gamma) are in good agreement with previous measurements and recent theoretical
calculations for this dependence.
