Wave-function profile and SUSY breaking in 5D model with Fayet-Iliopoulos terms

Abstract

We systematically study VEVs of a gauge scalar field $\Sigma$ in a bulk U(1) vector multiplet and scalar fields in brane/bulk hypermultiplets charged under U(1) in the 5D $S^1/Z_2$ orbifold model with generic FI terms. A non-trivial VEV of $\Sigma$ generates bulk mass terms for U(1) charged fields, and their zero modes have non-trivial profiles. In particular, in the SUSY-breaking case, bosonic and fermionic zero modes have Gaussian profiles. Such non-trivial profiles are useful to explain hierarchical couplings. A toy model for SUSY breaking is studied, and it yields sizable $D$-term contributions to scalar masses. Because the overall magnitude of $D$-term contributions is the same everywhere in the bulk and also on both branes, we have to take into account these contributions and other SUSY-breaking terms to obtain a realistic description. We also give profiles and mass eigenvalues of higher modes.

Comments: 23 pages, 23 figures; typos corrected, references updated