  The LHCb experiment will search for New Physics in Bs mixing. The Bs mixing
phase will be extracted from the measurement of the time-dependent CP asymmetry
in exclusive Bs decays governed by the b -> ccbar s quark-level transition.
Large New Physics effects can be discovered or excluded with the data collected
during the very first physics run of LHC. Based on Monte Carlo simulations of
the LHCb detector, the expected sensitivity with 2 inverse fb on the
CP-violation parameter phi_s is sigma(phi_s) = 0.022.
