Measurement of time-dependent CP asymmetry in B^{0}→K_{S}^{0}π^{0}γ decays

We measure the time-dependent CP asymmetry in B0→KS0π0γ decays for two regions of KS0-π0 invariant mass, m(KS0π0), using the final BABAR data set of 467×106 BB̅ pairs collected at the PEP-II e+e- collider at SLAC. We find 339±24 B0→K*0γ candidates and measure SK*γ=-0.03±0.29±0.03 and CK*γ=-0.14±0.16±0.03. In the range 1.1<m(KS0π0)<1.8  GeV/c2 we find 133±20 B0→KS0π0γ candidates and measure SKS0π0γ=-0.78±0.59±0.09 and CKS0π0γ=-0.36±0.33±0.04. The uncertainties are statistical and systematic, respectively.