UC Berkeley

We present a study of τ -→π -KS0KS0(π0) ν τ and τ -→K -KS0KS0(π0) ν τ decays using a data set of 430 million τ lepton pairs, corresponding to an integrated luminosity of 468fb -1, collected with the BABAR detector at the PEP-II asymmetric energy e +e - storage rings. We measure branching fractions of (2.31±0.04±0.08) ×10 -4 and (1.60±0.20±0.22)×10 -5 for the τ -→π -KS0KS0ν τ and τ -→π -KS0KS0π0ν τ decays, respectively. We find no evidence for τ -→K -KS0KS0ν τ and τ -→K -KS0KS0π0ν τ decays and place upper limits on the branching fractions of 6.3×10 -7 and 4.0×10 -7 at the 90% confidence level. © 2012 American Physical Society.