  Direct CP violation in the b->sgamma process is a sensitive probe of physics
beyond the Standard Model. We report a measurement of the CP asymmetry in B ->
X_s gamma, where the hadronic recoil system Xs is reconstructed using a
pseudo-reconstruction technique. In this approach there is negligible
contamination from b->dgamma decays, which are expected to have a much larger
CP asymmetry. We find ACP = 0.002 +- 0.050(stat.) +- 0.030(syst.) for B -> Xs
gamma events having recoil mass smaller than 2.1 GeV/c^2. The analysis is based
on a data sample of 140 /fb recorded at the Upsilon(4S) resonance with the
Belle detector at the KEKB e+e- storage ring.

High Energy Physics - Experiment