A fourth generation, anomalous like-sign dimuon charge asymmetry and the LHC

Abstract

A fourth chiral generation, with m_t' in the range ~ (300-500) GeV and a moderate value of the CP-violating phase, can explain the anomalous like-sign dimuon charge asymmetry observed recently by the D0 collaboration. The required parameters are found to be consistent with constraints from other B and K decays. The presence of such quarks, apart from being detectable in the early stages of the LHC, would also have important consequences in the electroweak symmetry breaking sector.