Mapping and probing Froggatt-Nielsen solutions to the quark flavor puzzle Journal Article uri icon

Overview

abstract

  • The Froggatt-Nielsen (FN) mechanism is an elegant solution to the flavor problem. In its minimal application to the quark sector, the different quark types and generations have different charges under a U(1)X flavor symmetry. The SM Yukawa couplings are generated below the flavor breaking scale with hierarchies dictated by the quark charge assignments. Only a handful of charge assignments are generally considered in the literature. We analyze the complete space of possible charge assignments with -Xqi-≤4 and perform both a set of Bayesian-inspired numerical scans and an analytical spurion analysis to identify those charge assignments that reliably generate SM-like quark mass and mixing hierarchies. The resulting set of top-20 flavor charge assignments significantly enlarges the viable space of FN models but is still compact enough to enable focused phenomenological study. We then apply our numerical methodology to demonstrate that these distinct charge assignments result in the generation of correlated flavor-violating four-quark operators characterized by significantly varied strengths, potentially differing substantially from the possibilities previously explored in the literature. Future precision measurement of ΔF=2 observables, along with increasingly accurate SM predictions, may therefore enable us to distinguish among otherwise equally plausible FN charges, thus shedding light on the UV structure of the flavor sector.; ; ; ; ; Published by the American Physical Society; 2025; ; ;

publication date

  • January 30, 2025

Date in CU Experts

  • February 2, 2025 7:13 AM

Full Author List

  • Cornella C; Curtin D; Neil ET; Thompson JO

author count

  • 4

Other Profiles

International Standard Serial Number (ISSN)

  • 2470-0010

Electronic International Standard Serial Number (EISSN)

  • 2470-0029

Additional Document Info

volume

  • 111

issue

  • 1

number

  • 015042