Galactic Positrons as a Probe of Large Extra Dimensions

TL;DR

This paper explores how large extra dimensions could produce observable positron fluxes in our galaxy through decaying Kaluza-Klein modes, providing new constraints on the ADD model based on gamma-ray observations.

Contribution

It proposes that Kaluza-Klein modes in large extra dimensions can be trapped in the galactic halo and decay, leading to observable signals that constrain the ADD model.

Findings

Constraints on the ADD model from gamma-ray observations.

Predicted positron fluxes from decaying Kaluza-Klein modes.

Implications for large extra dimensions theories.

Abstract

In the last decade, there has been increased interest in the possibility that the Universe contains large additional dimensions. In this article it is proposed that the Kaluza-Klein modes which are predicted to exist in such models will be trapped in the galactic halo, and that the subsequent decays of these modes in the present will generate an observable flux of positrons and $\gamma$-rays from the galactic core. In particular, by restricting the rate of production 511 keV photons to be below that observed by the INTEGRAL satellite, a new set of constraints are imposed on the ADD model.