Flavor structure with multi moduli in 5D supergravity

TL;DR

This paper explores 5D supergravity with multiple moduli, deriving a 4D effective theory that addresses flavor structures and soft scalar mass issues, and presents a model with stabilized moduli and realistic sparticle spectrum.

Contribution

It introduces a multi moduli framework in 5D supergravity, deriving the effective theory, and demonstrates how it can resolve tachyonic masses and produce realistic flavor structures.

Findings

Additional terms in the Kahler potential prevent tachyonic soft masses.

Flavor structure differs from single modulus models with hierarchical Yukawas.

A concrete model stabilizes moduli and predicts low-energy sparticle spectrum.

Abstract

We study 5-dimensional supergravity on S^1/Z_2 with a physical Z_2-odd vector multiplet, which yields an additional modulus other than the radion. We derive 4-dimensional effective theory and find additional terms in the Kahler potential that are peculiar to the multi moduli case. Such terms can avoid tachyonic soft scalar masses at tree-level, which are problematic in the single modulus case. We also show that the flavor structure of the soft terms are different from that in the single modulus case when hierarchical Yukawa couplings are generated by wavefunction localization in the fifth dimension. We present a concrete model that stabilizes the moduli at a supersymmetry breaking Minkowski minimum, and show the low energy sparticle spectrum.