Particle production in string cosmology models

TL;DR

This paper calculates particle spectra generated during a string cosmology inflation phase, revealing varied spectral behaviors depending on model parameters and particle types, and introduces a symmetric approximation scheme.

Contribution

It introduces a symmetric approximation scheme for particle spectra in string cosmology, providing a foundation for further studies on relics, dark matter, and anisotropies.

Findings

Spectra depend on model parameters and particle types.

Spectra can increase or decrease with frequency.

A symmetric approximation scheme is proposed.

Abstract

We compute spectra of particles produced during a dilaton-driven kinetic inflation phase within string cosmology models. The resulting spectra depend on the parameters of the model and on the type of particle and are quite varied, some increasing and some decreasing with frequency. We use an approximation scheme in which all spectra can be expressed in a nice symmetric form, perhaps hinting at a deeper symmetry of the underlying physics. Our results may serve as a starting point for detailed studies of relic abundances, dark matter candidates, and possible sources of large scale anisotropy.