Exotic signals of vectorlike quarks

Vectorlike fermions are an important target for hadron collider searches. We show that the vectorlike quarks may predominantly decay via higher-dimensional operators into a quark plus a couple of other standard model fermions. Pair production of vectorlike quarks of charge 2/3 at the LHC would then lead to a variety of possible final states, including t t ¯ + 4 τ , t b ¯ ν + 3 τ , t t ¯ + 4 μ , t b ¯ ν + 3 μ or t t ¯ + 4 b . Additional channels ( b b ¯ + 4 τ , 4 t + b b ¯ , 6 b , etc) arise in the case of a vectorlike quark of charge −1/3. If the vectorlike quark decays into three light quarks, then the 3 j + 3 j signal is more difficult to observe, and the vectorlike quark mass is almost unconstrained by current searches.