Constraints on Cosmic Super-Strings from Kaluza-Klein Emission

TL;DR

This paper investigates how cosmic super-strings emit Kaluza-Klein particles, deriving constraints from Big Bang Nucleosynthesis that complement gravitational wave observations, thereby narrowing the viable parameter space of string models.

Contribution

It provides a detailed analysis of KK particle production by cosmic super-strings and establishes new cosmological constraints on string theory parameters.

Findings

KK emission constrains string tension and coupling parameters

Big Bang Nucleosynthesis limits KK particle abundance

Complementary to gravitational wave detection regions

Abstract

Cosmic super-strings interact generically with a tower of light and/or strongly coupled Kaluza-Klein (KK) modes associated with the geometry of the internal space. We study the production of KK particles by cosmic super-string loops, and show that it is constrained by Big Bang Nucleosynthesis. We study the resulting constraints in the parameter space of the underlying string theory model and highlight their complementarity with the regions that can be probed by current and upcoming gravitational wave experiments.