CMB constraints on the inflaton couplings and reheating temperature in $\alpha$-attractor inflation

TL;DR

This paper explores how CMB observations can constrain the inflaton's couplings and reheating temperature in $ ext{alpha}$-attractor inflation models, potentially revealing fundamental microphysical parameters of the early universe.

Contribution

It demonstrates that viable regions exist where CMB data can determine inflaton couplings, linking observational data to microphysical parameters in inflation models.

Findings

CMB temperature fluctuations can constrain inflaton couplings.

Viable parameter space exists for measuring reheating temperature.

Method applicable to other single-field inflation models.

Abstract

We study reheating in $\alpha$-attractor models of inflation in which the inflaton couples to other scalars or fermions. We show that the parameter space contains viable regions in which the inflaton couplings to radiation can be determined from the properties of CMB temperature fluctuations, in particular the spectral index. This may be the only way to measure these fundamental microphysical parameters, which shaped the universe by setting the initial temperature of the hot big bang and contain important information about the embedding of a given model of inflation into a more fundamental theory of physics. The method can be applied to other models of single field inflation.