LHC Signatures of a Vector-like b'
  Many beyond the standard model extensions predict the existence of heavy vector-like fermions. We study the LHC signatures of one such heavy vector-like fermion, called b', with electromagnetic charge -1/3 like the SM b-quark, but which could generically have different SU(2)_L and U(1)_Y quantum numbers. Our emphasis will be on the phenomenology due to b <-> b' mass-mixing, present after electroweak symmetry breaking. We focus on aspects which distinguish a vector-like b' from a chiral b' and include tree-level decays of the b' into t W, b Z and b h final states. While our analysis is largely model-independent, we take as a motivating example warped-space models in which a vector-like b' appears as the custodial partner of the top-quark. 
Shrihari Gopalakrishna, Tanumoy Mandal, Subhadip Mitra, Rakesh   Tibrewala
hep-ph