Search for heavy bottom-like quarks in 4.9 fb−1 of pp collisions at √s=7 TeV
Results are presented from a search for heavy bottom-like quarks, pair-produced in pp collisions at √s=7 TeV, undertaken with the CMS experiment at the LHC. The b′ quarks are assumed to decay exclusively to tW. The b′b¯¯¯′→tW−t¯W+ process can be identified by its distinctive signatures of three leptons or two leptons of same charge, and at least one b-quark jet. Using a data sample corresponding to an integrated luminosity of 4.9 fb−1, observed events are compared to the standard model background predictions, and the existence of b′ quarks having masses below 611 GeV/c 2 is excluded at 95% confidence level.