WIMP Dark Matter through the Dilaton Portal

TL;DR

This paper explores a model where dark matter interacts with the Standard Model via a dilaton from a nearly scale-invariant sector, analyzing experimental constraints and prospects for detection in the TeV mass range.

Contribution

It introduces a dilaton portal framework for dark matter, fixing couplings through scale invariance and analyzing experimental constraints and detection prospects.

Findings

Dilaton exchange allows for a consistent dark matter model with TeV-scale parameters.

Current and future experiments can probe dark matter masses up to multi-TeV range.

The model remains viable within a parameter space where $f$, $m_\sigma$, and $m_\chi$ are similar, around 1-10 TeV.

Abstract

We study a model in which dark matter couples to the Standard Model through a dilaton of a sector with spontaneously broken approximate scale invariance. Scale invariance fixes the dilaton couplings to the Standard Model and dark matter fields, leaving three main free parameters: the symmetry breaking scale $f$, the dilaton mass $m_{\sigma}$, and the dark matter mass $m_{\chi}$. We analyze the experimental constraints on the parameter space from collider, direct and indirect detection experiments including the effect of Sommerfeld enhancement, and show that dilaton exchange provides a consistent, calculable framework for cold dark matter with $f,\,m_\sigma,\,m_\chi$ of roughly similar magnitude and in the range $\sim 1-10$ TeV. Direct and indirect detection experiments, notably future ground-based gamma ray and space-based cosmic ray measurements, can probe the model all the way to dark matter mass in the multi-TeV regime.