Flavor signatures of isosinglet vector-like down quark model

Understand

We consider a model where the standard model is extended by the addition of a vector-like isosinglet down-type quark b'.

• We perform a chi square fit to the flavor physics data and obtain the preferred central values along with errors of all the elements of the measurable 3 X 4 quark mixing matrix.
• The fit indicates that all the new-physics parameters are consistent with zero and the mixing of the b' quark with the other three is constrained to be small.
• The current flavor physics data rules out possibility of detectable new physics signals in most of the flavor physics observables.