Measurement of CP Asymmetries in B0->Ks Pi0 Pi0 Decays

The authors present a preliminary measurement of the time-dependent CP asymmetry for the neutral B-meson decay into the CP = +1 final state KS0π0π0, with KS0 → π+π- and π0 → γγ. They use a sample of approximately 227 million B-meson pairs recorded at the Υ(4S) resonance by the BABAR detector at the PEP-II B-Factory at SLAC. From a maximum likelihood fit they extract the mixing-induced CP-violation parameter SK#sub S##sup 0#π#sup 0#π#sup 0# = 0.84 ± 0.71(stat) ± 0.08(syst) and the direct CP-violation parameter CK#sub S##sup 0π#0π0 = 0.27 ± 0.52(stat) ± 0.13(syst), where the first uncertainty is statistical and the second systematic