Light PIDM in Warped Extra Dimensions

TL;DR

This paper proposes a new warped extra-dimensional model for Planckian Interacting Dark Matter (PIDM) where dark matter can be a light composite state, enabling freeze-in production at TeV-scale reheating temperatures, unlike traditional heavy PIDM models.

Contribution

It introduces a warped five-dimensional UV-DB-IR brane setup allowing light composite PIDM with gravitational interactions, expanding the viable mass range and production mechanisms.

Findings

Light composite PIDM can be produced via freeze-in at TeV-scale reheating.

The model accommodates dark matter masses from 1 MeV to 1 TeV.

Viable gravitational interactions are maintained with suppressed couplings.

Abstract

Traditional Planckian Interacting Dark Matter (PIDM), which interacts exclusively through gravity, typically requires heavy DM candidates (with mass $10^3-10^{15}$ GeV) and very high reheating temperature ($T_{\rm rh}\gtrsim 10^{15}$ GeV). In this article, we explore a novel realization of PIDM in warped five-dimensions, consisting of an "Ultra Violet"$-$"Dark"$-$"Infra Red" (UV-DB-IR) brane setup, where the DM can be a Dark brane composite light state with mass 1 MeV $-$ 1 TeV. The DM sector is assumed to interact solely via gravity in five-dimensions. After orbifolding and performing a Kaluza-Klein (KK) decomposition, the DM is assumed to be localized onto the DB, which is positioned in the extra-dimension such that the DM interacts with both the massless graviton and its massive KK excitations, with suppressed couplings to remain consistent with the ethos of the PIDM framework. The light (heavy) Standard Model matter is assumed to be localized near UV (IR) branes for the geometric Froggatt-Nielsen mechanism, while their KK modes are localized close to the IR brane. We show that this construction allows for a viable and efficient freeze-in production mechanism for light composite PIDM, consistent with TeV-scale reheating temperature.