Masses and decay constants of bound states containing fourth family quarks from QCD sum rules

Abstract

The heavy fourth generation of quarks that have sufficiently small mixing with the three known standard model families form hadrons. In the present work, we calculate the masses and decay constants of mesons containing either both quarks from the fourth generation or one from the fourth family and the other from known third family standard model quarks in the framework of the QCD sum rules. In the calculations, we take into account two-gluon condensate diagrams as nonperturbative contributions. The obtained results reduce to the known masses and decay constants of the (b) over barb and (c) over barc quarkonia when the fourth family quark is replaced by the bottom or charm quark.