Trigger, reconstruction and physics performances in LHCb

LHCb is one of the four major experiments that will take data at the LHC, due to start operation in 2007. The primary aims of LHCb are to perform precision tests of CP violation and to search for new physics in b hadron decays. About 10^12 bb pairs will be produced in LHCb per 10^7 seconds (a nominal year) in pp collisions with a luminosity of 2x10^32 cm^-2 s^-1. A large, high-purity sample of b hadrons, decaying in a variety of channels, will be accumulated. LHCb will perform a detailed study of B meson mixing, precise measurements of the angles of the unitary triangle and investigations of rare decays in b hadrons, looking for new physics in loop-induced processes. The LHCb detector is optimised to reach these physics goals. Here a brief description of the reconstruction performance is given, and the sensitivities in typical channels for the study of Bs mixing, CP violation and rare decays are summarised.