Charged Loops at the Cosmological Collider with Chemical Potential

TL;DR

This paper investigates how chemical potential mechanisms applied to charged scalars during inflation can produce detectable non-Gaussian signals in the primordial universe, with potential observational implications for 21cm cosmology.

Contribution

It analytically evaluates one-loop contributions to the bispectrum from charged scalars with chemical potential, revealing parametric dependencies and potential signals.

Findings

Signal strength $f_{NL} \\sim 0.01$ is achievable within theoretical control.

Potential detectability by 21cm tomography.

Application to colored Higgs bosons in GUT models.

Abstract

Cosmological collider physics allows the detection of heavy particles at inflationary scales through their imprints on primordial non-Gaussianities. We study the chemical potential mechanism applied to a pair of charged scalars. We analytically evaluate the resulting one-loop contribution to the bispectrum, using the spectral decomposition. In this way we are able to determine the parametric dependences for both the signal and the background. We show that a signal strength $f_{\mathrm{NL}}\sim O(0.01)$ can be obtained within theoretical control, potentially reachable by 21cm tomography. As an application we consider the colored Higgs bosons in $\mathrm{SU}(5)$ supersymmetric orbifold grand unification with masses $M\lesssim10^{15}\:\mathrm{GeV}$.