Experimental constraints on fourth generation quark masses

  title={Experimental constraints on fourth generation quark masses},
  author={Phạm Quang Hưng and Marc A. Sher},
  journal={Physical Review D},
The existing bounds from CDF on the masses of the fourth generation quarks, t{sup '} and b{sup '}, are reexamined. The bound of 256 GeV on the t{sup '} mass assumes that the primary decay of the t{sup '} is into q+W, which is not the case for a substantial region of parameter space. The bound of 268 GeV on the b{sup '} mass assumes that the branching ratio for b{sup '}{yields}b+Z is very large, which is not only not true for much of parameter space, but is never true for b{sup '} masses above… Expand

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