Effective reheating in Gauss--Bonnet inflation with $μ(φ,X)$ coupling
Abstract
We study effective reheating in a scalar--Gauss--Bonnet inflationary model with a phase-space-dependent coupling , in which a compact field-space feature is combined with a bounded kinetic gate. The modified inflationary background determines the pivot-scale quantities and the effective energy density at the end of inflation. These quantities are then used to derive the reheating duration and temperature through the thermal-history matching relation. We first perform two fixed-pivot reference scans by varying the overall Gauss--Bonnet strength and the kinetic parameter separately. For the reference parameter choices, increasing either parameter increases and decreases for the selected reheating equations of state. Additional benchmark calculations clarify how these variations depend on the dynamical regime of the model. In the scan, the increase in and the decrease in persist, although both variations become strongly suppressed when the coupling is more localized or when the end of inflation is controlled more strongly by the E-model potential. In the scan, stronger field-space localization and kinetic saturation can instead lead to a slight decrease in and an increase in as is increased. When the bounded kinetic contribution is considered together with a weaker overall Gauss--Bonnet interaction, the resulting changes in the reheating quantities become nearly negligible. The fixed-pivot predictions of the representative and alternative benchmarks are compared with CMB constraints.These reheating constraints are then discussed for four representative values of the effective equation-of-state parameter, and .
Cite
@article{arxiv.2608.02506,
title = {Effective reheating in Gauss--Bonnet inflation with $μ(φ,X)$ coupling},
author = {Ali Seidabadi and Sara Saghafi and Kourosh Nozari},
journal= {arXiv preprint arXiv:2608.02506},
year = {2026}
}
Comments
25 pages, 7 figures, 9 tables