Search for Bs --> mu+mu- and Bd --> mu+mu- Decays with 2fb-1 of ppbar Collisions

We have performed a search for Bs-->mu+mu- and Bd-->mu+mu- decays in ppbar collisions at sqrt(s) = 1.96TeV using 2fb-1 of integrated luminosity collected by the CDF II detector at the Fermilab Tevatron Collider. The observed number of Bs and Bd candidates is consistent with background expectations. The resulting upper limits on the branching fractions are B(Bs-->mu+mu-) < 5.8X10^-8 and B(Bd-->mu+mu-) < 1.8X10^-8 at 95% C.L.