F-Term Hybrid Inflation with T-Model K\"ahler Geometry and Beyond

TL;DR

This paper explores F-term hybrid inflation models within GUT frameworks, emphasizing the role of Kähler geometry and corrections, and assesses their compatibility with observational data and cosmic string signatures.

Contribution

It introduces a comprehensive analysis of FHI with specific Kähler geometries, incorporating supergravity and corrections, and evaluates their observational viability and cosmic string implications.

Findings

Viable FHI models without extrema along the inflationary path.

Model predictions depend on internal space curvature and tadpole parameter.

Potential detection of gravitational waves from cosmic strings.

Abstract

We analyze F-term hybrid inflation (FHI) within various grand unified theories (GUTs) in the presence of a K\"ahler potential for the inflaton field which parameterizes the K\"ahler manifolds $SU(1,1)/U(1)$ or $SU(2)/U(1)$. We take into account supergravity, radiative, and soft supersymmetry-breaking corrections to the tree-level potential and find that viable FHI can be realized without extrema along the inflationary trajectory for a broad region of the parameter space. For selected superpotential parameters the models' predictions are largely influenced by the curvature of the internal space and the magnitude of the tadpole parameter which are constrained so as to achieve compatibility with the current ACT and SPT data. We also discuss the formation of cosmic strings and their associated gravitational wave signals, potentially detectable by current and upcoming experiments.