The $g-2$ of the Muon in Localized Gravity Models

The $(g-2)$ of the muon is well known to be an important model building constraint on theories beyond the Standard Model. In this paper, we examine the contributions to $(g-2)_\mu$ arising in the Randall-Sundrum model of localized gravity for the case where the Standard Model gauge fields are in the bulk and the fermions lie either on the TeV brane or are also allowed to propagate in the bulk. In the case of bulk fermions, we find that strong constraints, of order 100 TeV, can be placed on the mass of the lightest gauge Kaluza-Klein excitation for a wide range of the 5-dimensional fermion mass parameter. The contributions to $(g-2)_\mu$ from gravity are also discussed. Our results suggest that placing the Standard Model fields in the 5-dimensional bulk is disfavored, unless other new physics is present and cancels these effects.