The ATLAS B-physics program

The large b quark production cross-section at the LHC will allow sensitive tests of possible new physics contributions. The ATLAS B-physics program includes the new physics search, such as measurement of the CP violating phase phi_s of the Bs system, searching for anomalous rates of the rare B-decay channel: Bs --> mu mu, well as precise test of QCD by studying of the production mechanisms of bb-bar pairs, beauty baryon polarization, and lifetime measurement in the earlier stage of the data taking. The strategy of the ATLAS for B-physics strongly depends on the ATLAS trigger system decision which will be different in the different luminosity periods. This article gives an overview of ATLAS B-physics studies for low and high luminosity periods, including description of ATLAS trigger with an emphasis on the B-physics selections.